Transistorisierter Tischanalogrechner RA 742 — Beschreibung

Complete English translation of the original German-language document (108 pages).

[page 1: cover page — Transistorized Desk Analog Computer RA 742, Description (Beschreibung), TELEFUNKEN]

[page 2: figure/publisher page only — ALLGEMEINE ELEKTRICITÄTS-GESELLSCHAFT AEG-TELEFUNKEN, Geschäftsbereich Nachrichtentechnik, 775 Konstanz, Baarstraße 1–5. Order number AEG 09 50.]

1. Technical Overview

Section	Title	Page
1.1.	Application Areas	2
1.2.	Delivery and Order Designations	2
1.3.	Technical Data	8
1.4.	Modules and Functions	16
1.4.1.	Amplifiers	16
1.4.2.	Computing Elements	—
1.4.2.1.	Fixed-Coefficient Potentiometers	18
1.4.2.2.	Variable Potentiometers	—
1.4.2.3.	Flip-Flops	—
1.4.2.4.	Time Dividers	—
1.4.2.5.	Measure or Set Appropriate Flip-Flop Switches	—
1.4.3.	Arrangement of the Programming Field	—
1.4.4.	Patch Field for Converter Devices (e.g., Non-Linear Elements)	—

2. Operation

Section	Title	Page
2.1.	Starting the Computer	42
2.1.1.	Mains Switch	42
2.1.2.	Switching of Computing Amplifiers	42
2.1.3.	Switching of Output Amplifiers	—
2.2.	Programming	—
2.2.1.	Setup of the Computing Amplifiers	44
2.2.2.	Computing Amplifier Switches	—
2.2.3.	Operating Modes	—
2.2.3.1.	Setup of the Fixed Coefficient Potentiometers	45
2.2.3.2.	Variable Potentiometers	—
2.2.3.3.	Patching and Programming of the Function Generators	—
2.4.1.	Pause	—

[page 4: continuation of Table of Contents]

Section	Title	Page
2.4.2.	Manual Computing	39
2.4.3.	Repetitive Computing	39
2.4.4.	Squaring	39
2.4.5.	Multiplier	—
2.4.6.	Potentiometer Setting (Static POT)	40
2.4.7.	Hold	—
2.4.8.	Output	—
2.5.	Measurement at the Computing Amplifier Output	41
2.5.1.	Oscilloscope Measurement at the Computing Amplifier	—
2.5.2.	Programming Measurement on Computing Amplifier	41
2.6.	Measuring Procedure on Computing Amplifier	43
2.7.	Automatic Operation with Digital Computers	—
3. Maintenance	—
3.1.	Testing of Input and Control Devices	—
3.2.	Testing of the Supply Voltage	—
3.3.	Testing of Relays	—
3.3.1.	Hold Relay	64
3.3.2.	Testing of the Function Generator Relays	—
3.3.3.	Testing of the Relay Switches	64
3.3.4.	Testing of the Fixed Coefficient Potentiometers	—
4. Commissioning	—
4.1.	Factory Setting	67
4.2.	Cable Mounting	—
4.3.	Checking Inputs and Control Devices	70
4.4.	Replacement of the Output Amplifiers	71
4.5.	Cable Mounting	—
4.5.1.	Amplifier Positioning	—
4.5.2.	Replacement of the Input and Control Devices	—
4.5.3.	Adjustment of All Amplifiers	—
4.5.4.	Assembly and Testing of Switchboards	72
5. Circuit Descriptions	—
5.1.	Amplifier Circuit	77
5.1.1.	Amplifiers	77

[page 5: continuation of Table of Contents]

Section	Title	Page
5.1.2.	Self-Control	78
5.1.3.	External Control	78
5.1.4.	Pause	78
5.1.5.	1× Computing	79
5.1.6.	Spring Control with Connected Recorder	81
5.1.7.	Bright Control of a Connected Cathode-Ray Oscilloscope	81
5.1.8.	Clock	81
5.1.9.	Computing with Hold	82
5.1.10.	Repetitive Computing	82
5.1.11.	Continuous Computing	83
5.1.12.*	Switching Registers	83
5.1.13.	Overriding Hold Circuit	83
5.1.14.	Potentiometer Setting	84
5.1.15.	Nulling	84
5.1.16.	Static Testing	85
5.1.17.	Operating Mode Indicator Lamps	85
5.1.18.	Measuring Device	87
5.2.	Power Supply	87

Explanatory Notes

The present description is intended to inform the user about the technology of the desk analog computer, and to enable its operation and maintenance. In addition, it contains important notes for commissioning. For the effective use of this device, a separate “Computing Manual for Analog Computers” is available.

The structure of the description is arranged so that the first main section provides all knowledge necessary for operation, while the following sections “Operation,” “Maintenance,” and “Commissioning” describe the manually required activities. The latter are, for maximum clarity, arranged in continuously numbered brief paragraphs whose sequence corresponds to the chronological order of the activities to be carried out. The fifth section contains further details that allow the specialist to go beyond the measures described in Section 4 for commissioning.

Regarding the circuit diagrams and wiring plans, it should be noted that all switches and relays, regardless of the individual operating states shown, are drawn in accordance with DIN in the non-actuated or de-energized state.

1. Technical Overview

1.1. Application Areas

[page 7: contains a photograph of the RA 742 desk analog computer with labeled components (Computing Amplifier Field, Function Generator, Coefficient Potentiometer, Programming Field, Display Device, Control Unit) and associated text]

Fig. 1 — Desk Analog Computer RA 742, Control Panel and Measurement Accessories

The desk analog computer RA 742 is a complete unit that makes it possible, in addition to simple mathematical operations, to simulate and investigate physical, technical, and economic processes with variable parameters. The ease of use of the analog computer allows the user — after a short familiarization period — to solve technical-mathematical and particularly differential-equation problems both analytically and graphically. The computer is equipped with all-electronically implemented modules.

1.2. Delivery and Order Designations

Depending on the requirements of the problems to be solved, different basic and expanded configurations can be selected. The standard configuration NW 801 is available in the form shown in Fig. 1 (Bild 1). The desk analog computer RA 742 is available as a rack version (Fig. 2). An additional plug-in unit (Zusatzgerät) is also available, which gives the user access to further devices that go beyond the measures described in Section 4.

[page 8: contains photograph of RA 742 in rack version (Fig. 2 / Bild 2) and additional descriptive text]

Fig. 2 — Desk Analog Computer RA 742, Rack Version

Accessory units, programming aids, and commissioning tools are available as options. For the desk version (Zusatzgerät NW 801) the following accessories are available for installation: The plug-in units (Zusatzgerät) provide the user with further devices beyond those covered in Section 4.

[page 9: contains photograph (Fig. 3 / Bild 3 — Function Slots) and tables]

Fig. 3 — Function Slots

Table 1 — Standard Equipment

Computing Elements	Basic Unit	Standard Configuration
Computing Amplifiers	—	23
— of which usable as:
Integrator/Summing Amplifier	—	8
Summing Amplifier (large)	—	7
Summing Amplifier (small)	—	4
Inverting Amplifier	—	4
Computing Coefficient Potentiometers	19	19
Function Generator Setting Unit	1	1
Variable Function Generators	—	2
Multipliers:
— fixed functions	—	4 (8)
Comparators	—	2
Function Switches	2	2
Exchangeable Programming Field	—	1

Table 2 — Parts List for RA 742 (S) with Order Designations

Assembly Group	Designation	Type	Unit	Order No.	Qty
Desk Frame		GER 742	55.3048.750		1
	Connecting Cable — Amplifier Outputs			55.3048.782	1
	Connecting Cable — Amplifier Inputs			55.3048.783	1

[page 10: continuation of Table 2 — Parts List]

Assembly Group	Designation	Type	Unit	Order No.	Qty
Computing Amplifiers and Display Unit	Computing Amplifier	FV 742	NW 1C	55.3048.275	1
		M 1C	55.3048.844		16
	Chassis	ACH 110	54.0701.001-09		—
	Reference Voltage ±10 V	HS 2-B	55.3048.873		1
	Reference Voltage ±20 V	HS 7-A	55.3048.874		1
	Earth Bus		55.3048.873		1
	Compensation/Regulation — 25/15 V Regulator	H-G B1	55.3000.121		3
	Comparator Amplifier	KV 1C	55.3003.042		2
	400 Hz Generator	KO 2-A	55.3003.053		1
	Coil-Fuse	HV M 3	55.3003.082		1
	Measuring Unit	MW 1	55.3040.839		2
	Clock/Timing Unit	A-23.1	55.3048.838		2
	Measuring Bridge Unit	GU B 2	55.3003.852		1
	Fuse Holder		55.3048.119		1
Function Generators	Function Generator	FG 742		55.3048.300	1
		FO 8		55.3048.843	4
	Function Generator Setting Unit	SFG 742	FG B	55.3048.838	2
		FG B	55.3048.840	2
	Variable Transistor Network	A/N 742	A/N V1	55.3005.020	—
Coefficient Potentiometers	Coefficient Potentiometer	PE 742		55.3048.750	1
Programming Field and Control Unit	Computing Amplifiers	SV 742	NW 1A	55.3048.400	4
	Computing Amplifiers		NW 1B	55.3048.845	4
	Computing Amplifiers
	Comparators	HGW M 111	H-G B1	55.3003.314	2
	Comparators	HGW M 142	H-G B1	55.3003.879	—

[page 11: continuation of Table 2 — Parts List]

Assembly Group	Designation	Type	Unit	Order No.	Qty
	Fixed-Coefficient Multipliers	SPM 134	FM 3B	55.3005.064	—
			FM 3B	55.3005.033	1
	Fixed-Logic Multiplier	SL-DG	H-G S1	55.3005.065	—
			PL S1		1
	Variable Multiplier	SPM 134	FM 3B	55.3005.033	—
Accessories	Accessories (Misc.)	ZUB 742		55.3040.29	1
			1 BES	22.3001.001/57	—
Measurement Unit	Potentiometer Meters			22.3001.460	40
	(e.g., Accessories with)			22.4999.056-04	—
Programming Panel	Panel – 0.15 s and longer			55.4442.064-11	—
	Panel – 0.40 m Blue and 1 m Yellow			55.4442.064-16	—
	Panel – 0.40 m and 1 m Yellow			55.4442.064-17	—
Comparators		GU B 3		55.3048.116	1
Fuse Holders				55.3048.119	—
Function Switches		SKV 10		55.3000.042	2
Comparators (add-on)		KOG B		55.3048.810	2
Variable-Function Potentiometers				55.3005.016	—
Compensation Measurement Unit				55.3040.811	1
Compensation Display (Schütz)		MAS 24-4		28.1900.401	—

[page 12: contains photographs of additional peripheral devices and their order numbers]

Accessories — Table 2 (continued)

Assembly Group	Designation	Type	Unit	Order No.	Qty
Switching Accessories	Einzel-/Dreier-Netzwerke	NWA 401		55.3005.000	—
	Electronic Amplifier Module	EA B		55.3003.783	—
	Amplifier Outputs			—	—
	Dual-Channel Output	ZV/M 742	ZV/N 742	55.3005.020-01	—
	Digital Oscilloscope	GVH 742		23-692	—
	Digital Voltmeter	GVH 745		—	—
	Magnetization Meter	DVM 745		23-693	—
	Multifunction Network System			28.1900.461	—
	MAS 24-4				—

Fig. 4 — Single/Triple Networks NWA 401

Fig. 5 — Electronic Amplifier Module EA B 801

[page 13: contains photographs of oscilloscope (OAS 700), dual-channel oscilloscope (OAS 871), digital voltmeter (DVM 748), and digital voltmeter DX4 102, with beginning of Technical Data section]

Fig. 6 — Oscilloscope OAS 700

Fig. 7 — Dual-Channel Oscilloscope OAS 871

Fig. 8 — Digital Voltmeter DVM 748

Fig. 9 — Digital Voltmeter DX4 102

1.3. Technical Data

Computing Amplifier Characteristics:

C. Amplifier Open-Loop Gain:

Input voltage range: ±10 V
Input resistance (d.c., transistors): > 100 kΩ
Open-loop gain for V = 1 (0-dB frequency): 200 kHz typ.
Input offset drift: 2.10 µV
Error after 8 hours, at rated operating point, temperature 23°C: 0.3 µV · °C⁻¹

Data of the Summing Amplifier:

Input resistance, Rating 1: 200 kΩ ± 0.25%
Input resistance, Rating 2: 20 kΩ ± 0.25%
Bandwidth (−3 dB): 15 kHz

[page 14: continuation of Technical Data]

Amplitude error, Inverter, static: 2 × 10⁻⁴ typ., 4 × 10⁻⁴ max.

Amplitude Error, Inverter, Dynamic:

Ra = 200 kΩ, f = 100 Hz: 2 × 10⁻⁴
Ra = 200 kΩ, f = 1 kHz: 2 × 10⁻²
Ra = 20 kΩ, f = 100 Hz: 1 × 10⁻⁴
Ra = 20 kΩ, f = 1 kHz: 2 × 10⁻³

Phase Error, Inverter:

Ra = 200 kΩ, f = 100 Hz: 0.03°
Ra = 200 kΩ, f = 1 kHz: 0.6°
Ra = 20 kΩ, f = 100 Hz: 0.004°
Ra = 20 kΩ, f = 1 kHz: 0.06°

Noise, Inverter, over full bandwidth:

Ra = 200 kΩ: 0.5 mV typ.
Ra = 20 kΩ: 0.2 mV typ.

Capacitive Load at Output:

Ra = 200 kΩ: 0.2 µF permissible

Output Resistance of the Inverter:

Ra = 200 kΩ: 100 mΩ

Data of the Integrator:

Initial Value Resistance: 20 kΩ ± 0.02%
Integration Capacitance:
- Integration factor 1: 5 µF
- Integration factor 10: 0.5 µF
- Integration factor 100: 0.05 µF
DC Error (room temperature, 23°C): 0.05%
Long-term drift: < 0.03% per year
Temperature drift: −100 × 10⁻⁶/°C
Amplitude error, static: 5 × 10⁻⁴ typ., 7 × 10⁻⁴ max.
Amplitude error, dynamic, f = 100 Hz: 1 × 10⁻⁴
Drift of the Integrator, k_a = 1: < 50 µV/s

Switching Times of the Integrator Switches:

Relay-controlled: 800 µs typ.
Electronically controlled: 1 µs typ.

Strobe times of the Integrating Switches (relay-controlled): ± 200 µs typ.

Coefficient Potentiometers:

Precision wire-wound resistor, 10-turn
Resistance: 5 kΩ
Resistance tolerance: ± 5 × 10⁻²

[page 15: continuation of Technical Data]

Linearity tolerance: ± 5 × 10⁻³
Resolution: 2 × 10⁻⁴
Protection: Current-limiting lamps, 30 mA at 10 V
Series resistance of the fuse: unloaded, 30 Ω

Precision Voltage Divider:

Number of steps: 10
Tolerance of the setting *): ± 1 × 10⁻³
Internal resistance: < 500 Ω

Compensation Measurement Device:

Accuracy of Setting: ≤ 1 × 10⁻³
Reproducibility: 2 × 10⁻⁴
Resolution: 1 × 10⁻⁴
Input impedance: > 4 kΩ
Input impedance, after comparison: ∞

Timer/Clock:

	Relay-controlled	Electronically controlled
Computing time, continuously adjustable in 3 ranges:	0.01 to 110 s	—
Pause time, 3 fixed times:	0.01, 0.1 and 1 s	—
Error in timing ():	1 × 10⁻³ ± 0.2 ms	1 × 10⁻³
Reproducibility:	2 × 10⁻⁴ ± 0.2 ms typ.	1 × 10⁻⁴
Non-linearity of timer voltage:	< 1 × 10⁻⁴

Non-Linear Elements:

All voltage-dependent errors are referenced to 2E = 20 V.

Parabolic Multiplier SPM 134:

Input voltage range: ± E max.
Number of diode segments: 10
Product error, static: < 1 × 10⁻³ FS
Product error, dynamic, f = 100 Hz: 1 × 10⁻⁴ FS
Input resistance: > 6 kΩ
Reference resistance of the following amplifier: 20 kΩ · 2 × 10⁻⁴

Parabolic Multiplier SPM 142:

Input voltage range: ± E max.

*) Load-compensated to an amplifier input I = 200 kΩ

[page 16: continuation of Technical Data — more non-linear elements]

SPM 142 (continued):

Number of diode segments per parabola: 5
Product error, static: < 1 × 10⁻² FS
Product error, dynamic, f = 100 Hz: 1 × 10⁻³ FS
Input resistance: 8 kΩ
Reference resistance of the following amplifier: 20 kΩ · 2 × 10⁻⁴

Variable Function Generator FG 742:

Number of segments: 20 (variable)
Input voltage range: ± E max.
Number of Kirchhoff points: ≤ 1 ms
Resolution of the Oscilloscope: 1 mV typ.
Linearity of the oscilloscope (basic): ± 1.5/0.6 (E “0”)
Setting Accuracy of Ordinate: ≤ ±E
Bandwidth of the following amplifier: 15–200 kHz

Reference resistor of the following amplifier: 200 kΩ · 2 × 10⁻⁴

Variable Function Generators, Series VAR 111 ¹):

Number of exchangeable Kirchhoff points: 8
Input voltage range: ± 1 ms
Number of Kirchhoff points: ≤ 35 ms
Entry/Read-in of the Kirchhoff points: 0.3 ms · 2/0.5

Polarity:

Designation	Übergangs-Eingang (Transfer Input)	Ausgang (Output)
VAR 221 (VAR 2 A)	negative	positive
VAR 231 (VAR 2 B) positive	negative
VAR 211 (VAR 2 C) negative	negative
VAR 241 (VAR 2 D) positive	positive

Fixed Function Generators:

SQF 113 and SQF 122 — [see specifications below]

Quadratic Function:

Transfer factor: → f
Input voltage range: ± 1 (FS)
Input resistance: 6 kΩ
Bezugswiderstand (reference resistance) of the following amplifier: 200 kΩ

Sine Function:

Transfer factor: sin (π/2 · U_E/E)
Input voltage range: ± 2.5/0.5
Bezugswiderstand of the following amplifier: 20 kΩ

Cosine Function:

Transfer factor: cos (π/2 · U_E/E) · (−)
Bezugswiderstand of the following amplifier: 20 kΩ

SCF 122:

Transfer factor: cos²
Bezugswiderstand: 20 kΩ

Logarithmic Function — ALF 111:

Transfer factor: LOG A
Bezugswiderstand: 20 kΩ

[page 17: continuation of Technical Data — more function modules]

Function Generator Series VAR 200 ¹):

Number of exchangeable Kirchhoff points: 8
Number of adjustable Kirchhoff points: ≤ 1 ms
Input voltage range: positive
Input resistance: 3 kΩ
Bezugswiderstand of the following amplifier: 20 lm · 200 kV/s
Entry of the Kirchhoff points: 0.3 lm · 2/0.5 (E, −I E)

Fixed Function Generators:

SQF 113 and SQF 122:

Parameter	SQF 113	SQF 122
Transfer factor	1·f² (u_E²)	—
Input voltage range	± 1	—
Input resistance	6 kΩ	—
Bezugswiderstand of following amplifier	200 kΩ	20 kΩ

Sine Function — SIF 133:

Transfer factor: sin(π/2 · U_E/E)
Input voltage range: ± 2.5/0.5
Amplitude error: 3.1 × 10⁻² to 10⁻³ FS
Bezugswiderstand of the following amplifier: 20 kΩ

Cosine Function — SCF 133:

Transfer factor: cos(π/2 · U_E/E)
Input voltage range: —
Amplitude error: 3.1 × 10⁻² to 10⁻³ FS
Bezugswiderstand: 20 kΩ

SCF 122:

Transfer factor: cos²
Bezugswiderstand: 20 kΩ

SGF 133 — Sine/Cosine Generator:

Übertragungsfaktor: sin/cos
Input voltage range: 0 to 4·E
Amplitude error: ± sin e.g., 0 bis… (3.5 × 10⁻² FS)
Bezugswiderstand: 100 kΩ

[page 18: continuation of Technical Data — further module specifications]

Logarithmic Function — ALF 111:

Transfer factor: 1/lg (100 · 1 + U_E) to 1/lg (100 + U_E)
Input voltage range: > 0
Input resistance: —
Amplitude error: 4 × 10⁻² FS
Bezugswiderstand of the following amplifier: 5–7 kΩ

Comparators (Relay) — MKM 111:

Comparison voltage range: ± 10 V
Input voltage range: ± 10 V
Sensitivity: ≤ 0.1 × 10⁻³
Number of switches: 2
Hysteresis (relay): ≈ ±10 mV
Switching time: at 2 V/s → (1 × 10⁻⁴ to 2 × 10⁻³) s

Contact state	Output — at output
Number of contacts:	2
Output voltage:	≈ max. ±10 V
Amplitude error, relay:	1 × 10⁻³
Switching time at SCH:	at 2 V/s → (1 × 10⁻⁴ to 2 × 10⁻³) s

Comparators (Electronic Switches) — SKM 111 :

Operating through Amplifier RA 742 BA 60, etc.
Comparison voltage: positive Kirchhoff
Number of switches: 2
Switching time: 1 × 10⁻³
Frequency response (SCH): (−1 × 10⁻³) × 10⁻³ FS

Qualifying (Qualifying = Bedingung) through Amplifier:

Appropriate other states from DEN 742 BA 60, etc.
appropriate other states: (−1 × 10⁻³) × 10⁻³ FS

Parabola Multiplier (Reference) — MAS 111 = Schalter:

Comparison voltage range · Amplifier: u_E → RA 742 BA 60 etc.
Comparison voltage: positive
Number of switches: 2
Switching time: 1 × 10⁻³ · 10⁻³
Qualifying through 11 Benus — Schalter

¹) Function generator series 100 and 200 can also be provided with electronic switches.

Computing Amplifier Network RA 742 b (see Fig. 10)

Amplifier type: Computing amplifiers SKV 742

Input impedance: approx. 2 V

Other data in accordance with VDE 0111, electronic elements (DEK 102 etc.)

Number of networks: 2

Channels per network: up to 24

Number of channels: up to 48

Network for programming according to Specification b, Bild 31

with function generators SKV 742: No. of programming steps selectable, up to 4

Number of networks: 2

Input impedance at the network inputs (“Folger”): 1

Transmission characteristic in “Folgers”: 1:1 oder 1:2

Offset (leakage voltage): in “Followers,” up to 2·10⁻⁴

Frequency response of “Followers”:

Due to a faulty connection: 2 x 10⁻⁴ Hz

Operational amplifier voltage range: 3–8 V

Effective output voltage of the amplifier in the range from 0 V to 1 MHz: approx. 3–8 V

Reference voltage: RSP 504

Effective output of the amplifier in the range:

Accuracy of the reference voltages: ±1%

Reference voltages: +10 V and −10 V

Stabilized voltages: 100 mA

Power supply:

Mains voltages: 110, 127, 150 kvar; 220 and 240 V

Mains frequency: 45 to 65 Hz

Power consumption: approx. 120 VA

Ambient conditions:

Temperature: 10 to 40 °C

Humidity: The machine shall be operated at a temperature of 10° C to 40° C

Dimensions

Computer unit:

Height: 670 mm
Width: 550 mm
Depth: 500 mm

Programming board:

Height: 215 mm
Width: 380 mm

Weight (fully equipped): approx. 105 kg

1.4. Construction and Function

1.4.1. Chassis Units

Upper Chassis Unit

The upper chassis unit contains on the left the assembly unit of computing amplifiers with 15 complete computing amplifiers (No. 1 to 15). On the front panel, alongside the associated null potentiometers and selector pushbuttons with built-in override indicator lamps, there are also null potentiometers, selector pushbuttons, and override indicator lamps for the multiplier-follower amplifiers (16 to 19) housed in the lower chassis unit, for the amplifiers of the function-generator chassis (U₁₁, U₁₂, U₂₁, U₂₂), and for the time-base and measuring amplifiers (“Z” and “Null”). The right-hand portion of the upper chassis houses the power supply assembly unit. On its front panel, alongside the mains switch, there is a measuring instrument and five fuse indicator pushbuttons. The indicator lamps on these pushbuttons serve as fault indicators for the automatic circuit breakers for the stabilized voltages. By pressing these pushbuttons, the individual voltages can be applied to the measuring instrument for test purposes. On the rear of the power supply unit there are four mains fuses, three sockets for connecting external equipment, the voltage selector, and the central earth terminal.

[page 22: Fig. 10 — Upper chassis unit]

[page 23: Fig. 11 — Middle chassis unit]

Middle Chassis Unit

The middle chassis unit contains 2 function-generator chassis with 4 associated potentiometer units. Each function-generator chassis can have the wiper of its potentiometer set to one of the programming values 1:1, 1:7, or 1:3 from the outside. Through illuminated pushbuttons on the right-hand side, the individual programming values can be selected from the outside; these pushbuttons can also be used for special functions at particularly important programming points. The potentiometer unit is connected to the function generator via a magnetic coupling, and specific pushbuttons are provided for the special Magnegraph functions.

On the rear of the middle chassis there is also a Magnegraph with function-generator patch areas and appropriately labeled pushbuttons for the programming unit.

Lower Chassis Unit

The lower chassis unit contains all the computing elements required for the analog-computer computation. There are 4 multiplier-follower amplifiers (Verfolger) and the programming unit for the mode control logic (i.e., the run-control logic).

The three status indicator lamps are provided for the initial mode (“Anfang”), the computing mode (“Rechnen”), and the hold mode (“Halten”), as well as the following:

Potentiometer amplifiers for the compensation potentiometer setting
Two Drucktasten for the Steckansatz function (Wippen)
Drucktasten for control of the Programmierautomaten

The appropriately labeled pushbuttons act as the control panel of the Programmierbrettes, i.e., the pushbutton panel at the front of the computer.

1.4.5. Computing Elements

1.4.5.1. Computing Amplifiers

The computing elements for the execution of the computing programs are summing amplifiers, integrators, and follower amplifiers.

In order to achieve the required accuracy with DC drift suppression, whose DC-level measurement is so large that the open-loop gain of the amplifier is at its peak value, the latter is produced by chopper stabilization of multiple operational amplifiers.

[page 24: Fig. 13 — Programming board]

[page 24: Fig. 14 — Schematic of a computing amplifier]

The error of the computing components of the computing amplifiers is less than 5 × 10⁻⁴ with respect to the computing capacitors and less than 2 × 10⁻⁴ with respect to the computing resistors. Fig. 15 shows the frequency response of an unloaded amplifier. The computing error due to the finite gain remains below 0.02 % up to a frequency of 100 Hz and is still below 0.2 % at 300 Hz.

[page 25: Fig. 15 — Frequency response of an unloaded amplifier]

[page 25: Fig. 16 — Amplitude and phase errors of the computing amplifier (20 kΩ inverter) as a function of frequency]

[page 26: Fig. 17 — Amplitude and phase errors of the computing amplifier (20 kΩ inverter) at higher frequencies as a function of frequency]

[page 26: Fig. 18 — Temperature drift of an amplifier as a function of temperature]

In Fig. 18, the drift dependence on temperature is shown. The drift at ambient temperature is up to 10⁻⁶ per 10 µV.

[page 26: Fig. 19 — Block diagram of a computing amplifier]

In the diagram, the Haupt- and Hilfsversterker are shown per computing amplifier arrangement. The Zusammenschaltung is given in Fig. 19.

For modulation of the chopper-type amplifier at the input frequency of 400 Hz, the following four computing amplifiers are designed. In addition to the normal computing amplifier Chopper, and in order to provide the best possible DC stability, the Zusammenschaltung des Rechenverstärkers has 10 chopper amplifiers for each Rechenverstärker.

Between 10 and 15 Rechenverstärkern, up to 10 and 15 Hilfsversterker from the left chassis are assigned. The 2 supplied Chopper im mittleren Einschub, which are common to the Summierer block, are grouped and provided as a joint summary block, for the Summiererschaltkreise.

The Befehls Hilfsversterker described above, can be Anfang, Rechnen, and Halten assigned; each can be operated as a separate computing amplifier.

Summierer (Summing amplifier)

Fig. 20a shows that, in the Verteiler technique, a Summierer combines several Eingangsversterker simultaneously and jointly provides a Vielfachverbindung. The Verbindung of the summing amplifier unit is so simple that independent settings of the Rückführungswiderstände are maintained and a final Einheitsverstärkung is established. The single Eingang to the Verteiler function and the Bewertungsfaktor of every single Eingangsverstärker is equal, i.e., for every single Spannung assigned. The Bewertungsfunktion is the same for the assigned Spannung (see following figure), and the Maschinenkennwert for the assigned Spannung amounts to 1, even for a different Maschinenwert Rechner.

The Rückführelemente are divided; for the inverter No. 1, one kind Rückführwiderstände (200 kΩ), and for a better Rückführung Spareverstärker, the same immediately below the Nennwert values of the Eingang Summiererschaltkreis amount to at most 2 × 10 mV.

The Verbindung von Vielfachverdrahtung has of course to the immediately following Eingangsversterker always the most immediately defined Rückführwiderstand (200 kΩ) connected. Further Spareverstärker elements follow through the programming bus (DEX 102).

[page 28: Fig. 20a — Summierer with multiple input branches and feedback]

Summierer

Fig. 20a shows that, in the Verteiler technique, a Summierer brings multiple branches together. The figure also shows that each branch Nz. 1, 3, and 10 has their individual Eingang Buchse to each single amplifier.

In addition, within a summing amplifier block always a Drucktaste “N” is located at the Programmierfeld side and the Eingang of the Integrators or Summierers is always available for programming.

Die Steuerspannungsanschlusse der N-1 and N-Schalter each individually represents. Thereby it is simplified, after individual setting, each Zeitkonstante del Zählers to connect at the exact time. An internally provided D/EX 102 connects to achieve a normally exchangeable Nenn- and Maßlattenfunktion, which can be used to Interaktionsspannungen in Zentraleinheit or Steckeinheit DEX 102 to reduce the Ausführwert components.

In the previously-described “Programmierautomaten,” “Folger” and “Vertikal Rolfer” then control all possible measurement of the Integrators automatically. The Integrators use the DEX-Steuerleitungen to achieve the appropriate Steuerspannung values, as well as the Eingang of the Vorkompensators. This enables the Rechner functioning in the individual components to be compared against specific desired values and for adjustments to be made accordingly.

In this process, the state at the Integratorteilblock becomes “Anfang,” “Folger” and “Vertikal” used from among the programmable part. The Zustandssteuerung shall proceed in detail through “Set-Befehl” and for the Verbindungschaltkreise the different modes can be controlled.

Should the Verstärker be functioning as a Summierer, it is already completely in the Gleichgewichtszustand (Ruhestellung). By activating the “Set-Befehl” at the Rechner, the Verteiler starts, and the Eingaben start to accumulate the Zeitintegral as they proceed.

Summierer with Multiple Input Branches and Higher Precision

[page 29: Fig. 20b — Summierer with multiple input branches and higher precision]

Each Verstärker keeps its Soll-Wert within the permitted Leerlaufspannung. When it is desired, for a separate Umkehrverstärker specific Spannung is needed, because the Verstärker itself as a Vorkompensator can only function if is connected there. In this manner, each Rechenverstärker the intended Einstellung must reach before any further switching sequence can be initiated.

Die Eingangsseite taugt sich nicht auf den negativen Wert der an Buchse “N” gelegten Programmierspannung (U_N) auf. Auf Anforderung legen die Kondensatoren sich an und die Integration beginnt. Bei “Halt” geht der Rechner in die gespeicherte Stellung zurück und bleibt in diesem Zustand bis Weiterschaltung erfolgt.

While in the Hold state, the Integratorbaustein acts on the negative input value. All Halten-related Zustandssteuerungen are individually controlled. Therefore, it is simplified to connect each Zeitkonstante of each Integrator and each Steuersignal at the Integrators DEX 102 separately, so that the appropriate Integrator-components as well as the Integrators D-1 and N-Schaltern-Einstellung shown in Bild 21 can be linked to the Ausführwert components DEX 102.

In the previously described “Programmierautomaten,” “Folger” and “Vertikal Rolfer” are further illustrated. All Halten-related Zustandssteuerungen are individually controlled. Thereby it is simplified to individually set each Zeitkonstante of the Rechenverstärkers to set an appropriate exchangeable Nenn- and Maßlattenfunktion which can control Interaktionsspannungen in DEX 102 to reduce the Ausführwert component and the Integrator-Steuerleitungen.

[page 31: Fig. 22 — Measured common-mode error of a Potentiometer amplifier]

Coefficient Potentiometers

Each Potentiometer is an individually adjustable, sufficiently precise precision element that is matched to each Rechner. Every single Potentiometer step has a Druckerhebung characteristic used as a Maschinen-setting value.

In the computer, there are 10 Mehrfachpotentiometer each with 40 Drucker positions assigned to each Rechenverstärker, i.e., each of them corresponds to 10 and 15 Hilfsversterker from the left chassis. Between 10 and 15 Potentiometerkennwert from the input block (200 kΩ Inverter), there is also one Anschluss.

The Befehl of the Hilfsversterker assigned, can be each operated as Anfang, Rechnen, and Halten assigned, and each operates as a separate Potiometer Rechenverstärker.

At one extreme, each Potentiometer is for the Druckerhöhung Kennwerteinstellung individually configured; at the other end, the Hilfs-Steckansatz can also be adjusted. Both functions are jointly operated through the N-Kanal.

[page 32: Fig. 23 — Measured sinusoidal errors of a function-multiplier]

[page 32: Fig. 24 — Schematic of a function-multiplier]

The four multipliers that the computer has available in its standard configuration are used as multiplier-followers (Verfolger-Verstärker) in the Verfolger technique. Four Multipliziererbaustein each contain 10 branches and are interconnected.

The multiplier allows the closest straight-line approximation to be selected from among Verteiler values of 0, 2, 2, 2, 3, and 5 (from the Folgeeingang) for the Verbindung connection.

1.4.5.6. Variable Function Generators

The function generators operate within the computing range from −10 V to +10 V.

The function generator consists of diode segments and computing resistors. The combinations of 00 diodes at the most favorable positions, combined with precise computing resistor values of ±0.1 %, form the Rückführschaltkreis. Each Rückführ segment is separately set for the precision Steckeinheit. A Steckfaktor Schaltbaugruppe allows the individual Maschinensteckwerte to be specified for each Kennlinie. In the operating range the function-generator Drucktasten output positions range between −10 V and +10 V approximately.

Each Rechner has one standard individually described function programming step. From the Potentiometern No. 1 and the associated Rechenverstärker, the individual Kennlinie value is established through the connected Rückführ segment. The Verbindungs-Einstellung is the same as the Maschinenwert Rechner.

The Rückführelemente shall be divided between: for inverter No. 1, one Rückführwiderstände (200 kΩ), and for additional precision Verbindung Spareverstärker, the same immediately below the Nennwert values of the Eingang block sum of at most 2 × 10 mV.

Each Potentiometer is for an individually adjustable, sufficiently precise programming step used as a Maschinen-setting value, whose individual stepping yields a Druckerhebung Kennwerteinstellung output.

To achieve accurate Potentiometer settings at the individual Steckeinheit, always a Drucktaste “N” connected at the Programmierfeld side is used, and the Eingang of the Integrators or Summierers is always connected.

For a properly formed connection including the Summiererschaltung, in every single Potentiometer step, i.e., in each Potentiometer Steckeinheit, the appropriate Rückführ segment must be available and connected.

At most 10 Mehrfachpotentiometer are used, each with a 40-step Drucker encoder positioned at each channel. The Potentiometer connections are within the Einheitsverstärker range. Between the 10 and 15 Potentiometers from the input block (200 kΩ inverter) there is also one connection. The Befehl of the Hilfs-Versterker assigned can be each operated as Anfang, Rechnen, and Halten assigned, and each operates as a separate Potentiometer Rechenverstärker.

Table 3 — Plug-in Units with Fixed Functions

Designation	Transfer function	Associated plug-in unit Type	Qty	Number of segments per unit
Parabolic multiplier SPM 134	x·y	PM3A	2	10
		PM3B	2	10
Parabolic multiplier SPM 142	x·y	PM4A	1	2×6
		PM4B	1	2×6
Squarer SQF 112	+x²	PM3B	2	10
Squarer SQF 122	−x²	PM3A	2	10
Sine function SSF 112	sin(π/2)x	SIN1A	1	10
		SIN1B	1	10
Sine function SSF 122	sin πx	SIN2A	1	10
		SIN2B	1	10
Cosine function SCF 112	cos(π/2)x	COS1A	1	10
		COS1B	1	10
Cosine function SCF 122	cos πx	COS2A	1	10
		COS2B	1	10
Arc function SAF 112	(2/π) arc sin x	ARC1A	1	7
		ARC1B	1	7
Logarithmic function ALF 111	+1/2 log 100x and −1/2 log 100x	LOG1A	1/2	2×5
Memory network ASN 742	−x / (1 + pT)	A-SN I	1/2	—
Electronic comparator switch AKE 742		A-KS6	1/2	—
Electromechanical comparator switch AKM 742		A-Ks5	1/2	—

Section 2.3.2.1. contains further details.

Table 3 also contains information about the associated Steckeinheit plug-in units — see the separate description types SKV 742 (RA 742 b). In these descriptions, the permissible number of connections at the Potentiometers of the individual computing elements is specified; these are to be respected. At the connection types VAM 741 it is possible to realize additional combinations of connections with −10 V and +10 V as desired, and switching combinations with 0 V and −10 V or 0 V and +10 V are also realizable with these elements.

The graphical illustrations in the lower part of Table 3 contain information about the mapping of the individual elements to the computing segments with the associated entry potentiometer characteristics. The precision applies likewise for each single combination of transfer functions shown in the last two columns.

1.4.5.2. Comparators

Comparators are used in the setting up of analog-computer programs to compare an amplifier voltage against a reference voltage (or against 0 V). In the computing unit RA 742, two kinds of comparators are available, and the analog-computer programs can thus be provided with digital-control Eingaben directly from the analog computing circuit.

[page 36: end of this page range]

1.4.5.7. Special Functions

To provide special functions, the programming field includes function-generating elements — diodes, resistors, and capacitors — which can be interconnected as required. The specific functions available depend on which elements are fitted in each individual case.

1.4.5.8. Manual Override for Stored Quantities

The manual override facility allows the user to alter the stored (initial) value of an integrator without interrupting the programming sequence. The control for this purpose is located on a separate panel. In this way it is possible to vary one stored quantity at a time and immediately observe the effect on the solution. Section 1.4.4.1 describes the corresponding controls.

1.4.5.9. Construction of the Programming Field

The programming field is the area in which the computing elements are interconnected. The connections run through a removable patch panel. The patch panel rows correspond to the bus-bar rows on the programming field. The number of rows is therefore determined by the number of bus bars in the particular system.

The normal connection method is realized through patch cables. The cables fit into the sockets of the programming field, which — depending on the position in the rows — are divided into input and output jacks or two parallel outputs.

The references to “Positions 1” and “5” in the description of the respective computing elements indicate the position of the corresponding sockets in the programming-field rows.

The “Variable Potentiometers” are connected to Positions 2, 10, 11, and 13 in the respective bus-bar rows. The potentiometers of the variable potentiometers F1 and F2 are connected to the bus rows at Positions 2, 10, 11, and 13 of the programming field.

The programming field is protected from the environment by a transparent cover. The cover can be removed by pressing the two snap latches inward. The patch cables and field components are connected while the cover is removed.

Note (Section 1.4.4.1): The programming field is illuminated. With the lighting switched on, individual patching mistakes are easier to detect.

[page 38: continuation of programming field description]

Forming a connection entails simultaneously pulling Plug 1 from its socket and — at the moment of pulling — pushing Plug 2 into the new socket. This procedure avoids unintended intermediate states.

In Figure 26, the programming field of a summator/integrator is shown; in Figure 27, the programming field of a summator/integrator pair is shown.

Potentiometer multipliers

The potentiometer multipliers are located at Positions 7 and 8 in the socket rows of the programming field. Their inputs and outputs appear in the upper socket row of the programming field together with those of the computing amplifiers. The lower socket row serves only as a parallel output and as a short-circuit socket for the free-running inverting amplifier that is activated as required (press the toggle-switch on the center slide-in unit). (Figure 28)

[page 39: figure-heavy page]

The two function-generator elements U71 and U72 (resp. U97 and U32) each have two input jacks and one parallel output. (Figures 26, 27)

Figure 26 — Programming-field patch arrangement of a summator/integrator

Figure 27 — Programming-field patch arrangement of a summator incorporating a free-running network

Figure 27 — Programming-field patch arrangement of a summator/integrator pair

Potentiometer multipliers

The potentiometer multiplier elements are located at Positions 7 and 8 in the socket rows of the programming field. The inputs and outputs…

[page 40 continues from p.39]

…of these amplifiers are served through a short-circuit socket by the socket “S” of the respective amplifier, immediately adjacent to socket “G” of the multiplier network. The subsequent amplifiers connected via the multiplier networks allow, at their Input 1, an additional summation of a quantity at the time of multiplication.

Note: Feedback resistor = 20 kΩ

Variable Function Generators

The socket fields of the two variable function generators F1 and F2 are located in the two upper socket rows of the programming field.

The inputs and outputs of each function generator F1 and F2 lie exclusively in the upper socket row of the function-generator field. The lower socket row (a single input, two parallel outputs) is provided solely for the free-running inverting amplifier that becomes available when the toggle-switch (depressed on the center slide-in unit) is activated. (Figure 28)

Figure 28 — Patch-field arrangement of a function generator

Function Sockets

The inputs and outputs for special functions N1 and N2 are arranged below the socket fields of the function generators. The connections required on the programming field — depending on the type of function plugged in — are specified in Section 2.3.2.5.

[page 41]

Coefficient Potentiometers

The potentiometer socket fields are numbered dials, as shown in the illustration. The outputs of the potentiometers are positioned in every other bus-bar row of the programming field. Potentiometer sockets 2, 10, 11, and 13 are connected there.

Comparators

The three green sockets of each comparator provide the comparator’s inputs and also the momentary state of the comparator’s output. They can also be used for setting the initial switching condition. (The sockets are assigned 1, 5, and 14 in the bus-bar numbering.)

At Position 14 there is a selection switch for setting the initial switching state: the available states are 0 (comparator output is negative) and 1 (comparator output is positive). This switch is used in conjunction with the hold function. The corresponding comparator element must be pre-set in the initial state assigned by this switch. (Figures 29a and 29b show comparator hysteresis.)

If the comparison of two quantities yields a small result, erroneous switching may result from noise. For this reason a small degree of hysteresis ε can be set in each comparator. This prevents noise-induced false switching. The hysteresis is set using the small Screw marked ε on the front of the comparator element. A tool suitable for rotating the ε-screw is found among the accessories.

[page 42: figure and continued text]

Figure 29 — Comparator hysteresis

The binary comparator outputs and the control inputs of the comparator switches are brought out at Connector 9 on the rear of the lower slide-in unit. They appear at the connection point of the digital add-on unit DEX 102, whose patch field it is — depending on the respective program — whether the switching control of the switches is done by elements of the digital add-on or directly by the comparator amplifier outputs.

If the digital add-on is not connected, a 30-pin spring-connector at Plug 9 links the comparator outputs to their associated switch control inputs (bridges c₁ – c₂ – c₃ and c₄ – c₅ – c₆).

Machine Unit = 10 Volts

The sockets for the reference voltage are arranged so that amplifier or potentiometer sockets can be short-circuited to them via short-circuit plugs as required. At the red sockets there is +10 V, at the blue sockets −10 V. Next to every free potentiometer a black socket at the computing element (amplifier ground) is found.

[page 43]

Controls

For the control of the RA 742 analog computer, the following controls are provided:

Buttons labeled “0 V” (= 0 Volt), “−5 V” (= −5 Volt, Reference Input):
- Button labeled “+10 V” (= +10 Volt, Reference Input)
- These reference voltages are always applied to the programming field.
The “D” controls complement the “Y+” and “Y−” controls. For a more detailed description of all “D” and “Y” controls refer to Section 1.4.4.1.

The controls of the “D” section are logically complementary to those of the “Y” section in the sense that pressing “D” when one of the “Y” states is active will toggle the behavior. The function names “D” and “Y” reference this complementary behavior, as is described further in the Section “Controls.”

The “Y” sockets are located on the front side of the lower slide-in unit and serve as the main integration control (modes: “Initial,” “Compute,” “Hold,” “Repetitive”). For naming conventions see Section 1.4.4.1.

[page 44]

Through the socket “M+,” there is no feedback connection; the amplifier is then connected in open-loop mode. “M−” causes the amplifier to be driven to negative saturation. With the socket “M+,” this connection may also be used for a momentary test of the patching. “Unused” but open sockets “M+” give rise to no problems.

The socket “M+” is controlled via the computing element labeled “M+,” and sockets “M−” via the socket “M−.” The connection via Plug “M+” drives the amplifier to positive saturation by the supplied high voltage.

Via the “D/M” socket it is possible — using the Digitalzusatz (digital add-on) DEX 700 or DEX 811 — to control the Potentiometereinstellung (potentiometer setting) of the designated computing element.

Table 4 — Properties of computing elements S and p, and the integration modes (S and p for all feasible computing elements)

Computing Element	S	p	Outputs
Potentiometers	1	1	Outputs

Negation-amplifiers	1	1	Outputs

The sockets at Positions 5 and 9 and also the Positions 5 and 9 in the neighboring socket rows form the patch-field connectivity for the computing elements. In Position 5 and 9 and in the associated bus rows a total of 13 sockets are available.

1.4.4.1. Amplifier Inputs for Functions

Potentiometer

The upper socket field of a Potentiometer is provided with a Wirth-numbered switch for a functional output reference. This applies to all socket rows. The socket “P” used for Potentiometer-Aussteuerung (potentiometer setting) is a parameter input for the corresponding digital control.

Socket D/M

This socket is located on the rear of the lower slide-in unit at Connector “D/M,” and allows the Digital add-on DEX 700 or DEX 811 to control the Potentiometereinstellung of the computing element.

Socket “VA”

The socket “VA” is provided at the top sockets of the lower slide-in unit and feeds the input of the Kurzschlußstecker (short-circuit plug).

Socket “D/M”

For controlling the Digitalzusatz DEX 700 or DEX 811, use the “D/M” socket located on the rear of the respective computing element.

Socket “Takt”

The “Takt” socket is used when a DV/O-Digitalzusatz is employed — it feeds the timing signal to the front of the computing element.

[page 46: figure only — RA 742 Programming Field layout diagram, color-coded socket legend]

Figure caption: RA 742 Programming Field — color coding of sockets:

White: cross-connections, transverse connections, free connections
Orange/brown: inputs, outputs, reference −10 V
Red: Reference +10 V
Black: Ground (computing ground)
Blue: −10 V
Green: Inputs, outputs, reference −10 V
Teal/turquoise: Switching inputs and switches
Yellow: Free

[page 47: figure and section headers]

Figure 31 — Arrangement of the plug-in elements

The enclosure and its installed components — slide-in units, computing elements, and operating controls — are described in the following sections on assembly, operation, and maintenance (Sections 4.2.3…).

5.1.1. Setup of the Device

5.1.2. Power Supply

The power supply voltage of the RA 742 must be set to either of the following values:
- 110 V and 127 (127) V: 4.4 A; and 220 V and 240 V: 2.2 A.
The power supply voltage may be selected to any of the positions stated.

5.1.3. Connecting the Output Sockets

The digital add-on device outputs are labeled in the front panels.

[page 48]

Oscillograph

Connections for the oscillograph for the Track-analog-computer RA 742 and for the TELEFUNKEN oscillograph OM 611 and OM 700 are described below.

The bridge between sockets “OSZ” (which are Befehlsgeber — command-generator — sockets) and Buchse (socket) “G” is checked; the upper Verbindungs-kabel (connecting cable) is inserted correctly. It is mandatory that the connecting cable first be inserted, then the socket “Qu” connected.
The sockets Buchse of the computing element (sockets “M−” and “Buchse Qu”).
Connecting the Buchse of the computing element to the Oszillograph (oscilloscope) via the switch at “Qu”:
- a. Press the socket socket — the connection is released.
- b. Using a suitable tool, press the bridge to close the switch, rotating back to make contact.
Connecting this socket to the Netz (mains) is done manually.

Switch Controls

The switch control of the computing element is provided by the Schalter (switch) inside the element:

Press the socket element — release the bridge.
Using the designated Buchse press the Schalter:
- a. Press the Buchse to release the bridge (switching open).
- b. Using the connecting tool, press the Schalter.

Digitalzusatz (Digital Add-on)

Setting the Digitalzusatz takes place via the sockets “D/Hb” on the computing element.
The digital add-on is initialized using the control elements on positions 20, 31 and 33 of the rear-panel DEX 102 board. The setting is realized by the programming field in association with the digital add-on for the Koeffizient-setting (coefficient setting) of the computing element RA 742. The position is carried out in a parallel configuration of sockets with a multi-purpose socket Verknüpfungs-verbindung.

5.1.4. Parallelschaltung — Parallel Connection

The Track-analog-computer RA 742 can be connected in parallel with another RA 742 machine by means of a dedicated connection cable, which is inserted into the appropriate sockets of the programming field and connected to the socket “Parallelschaltung” (parallel connection) on the rear panel.

[page 49]

…connected together. This gives the following additional features for single-machine operation as well. For the Parallelschaltung the following steps are necessary:

Press “Pause” on the Netzschalter (power switch).
Press “On” on Netzschalter.
Obtain the operating temperature levels “+10 V” and “−10 V” to operate within a stable range.

2.3. Potentiometers

For the analog operation, the analog modes can be selected from one of the three Betriebsarten (operating modes) listed below. The selection is done by:

a. Stecker (plugs) V+, V−, or V×.

2.3.1. Aufbau des Buchsenfeldes (Construction of the Patch Field)

[Illustration reference] The programming field is activated and controlled via the Buchsenfeld (socket field). The socket field is shown at right in Figure 32 — the Bediengerät (operating panel).

Figure 32 — Operating panel

[page 50]

2.3.2. Steuerung der Integratoren (Control of Integrators)

The analog computer employs several types of interconnected computing elements. The mode of the Integrator (integrator) is controlled via the Zustandsgeber (state generator), which can be connected via the Buchse (socket) “>S” to one of three positions corresponding to the three operating modes.

The normal control of an integrator’s operating mode — via one digital output at Positions 20, 31, and 33 — depends on the S- and t-inputs, determined as follows (see Section 1.4.2): individual bit-controlled integrators can be activated by DEX 102 at the programming field. Setting of the S- and t-inputs allows the operating mode selection. For each bit-controlled integrator, the digital add-on DEX 102 enables an independent mode control.

For allowing a machine to run freely, a Kurzschlußstecker (short-circuit plug) on the programming field at Positions 20, 31, and 33 is employed.

[page 51: figure-heavy page]

Figure 33 — Patch connections for a summator/integrator operating as a summator

Figure 34 — Patch connections for a summator/integrator operating as an integrator

Figure 36 — Patch connections for a multiplier

[Lower portion shows a Speicherpaar (memory pair) diagram with the following elements:]

Y_e — input
Y_a0 — initial output
Y_a — output

Symbole (Symbols):

normaler Speicher (normal memory store)
komplementärer Speicher (complementary memory store)

Beschaltung (Circuit):

Connections of Y_e, Y_a0, Y_a, and the p-feedback are shown for both normal and complementary memory configurations.

Figure 35 — Memory pair

[page 52]

The use of transistors T3-14-79 as simple Lenkungskondensatoren (steering capacitors) is also feasible, and this transistor can be placed in the Multiplicand-position. Additionally, the green socket “Y” at its programming-field position is connected.

2.3.2.1. Coefficient Potentiometers

The coefficient potentiometers allow the implementation of scaling factors for the transmission connections. It is important that the factor is taken into account throughout the computation, since it significantly influences the result during the computation.

The procedure is as follows:

Press “D/M” on the Bedieneinheit (operating unit).
Set Taste (key) “On” for Reference.
Define the Koeffizient (coefficient) value using the Kurzschlußstecker (short-circuit plug) at the programming field.
Actuate the appropriate free-setting Koeffizient-sockets.

The inputs to the coefficient potentiometers are three elements that — together with the variable function-generator inputs x₁, x₂, x₃ — can be interconnected with the large Summatorenbuchse (summator socket) of the output element.

[page 53]

2.3.5.6. Variable Function Generators

The function generator operates by means of its Einstellgeber (setting generators), with each individual Digitalzusatz (digital add-on) as well as comparator switches controlling the function. As a result, the digital switch controls the Potentiometereinstellung (potentiometer setting) or another computing element’s Digitalzusatz in combination with the comparator at the programming field.

From Figure 37, it can be seen that the Speichergenerator (memory generator) ZS also sets the Bearbeitungsanzahl (processing count) of the positive or negative maximum value set on the Digitalzusatz ZS of its own output position. The set value is then determined for each value, and the output of the function generator is compared with the desired curve with the aid of the comparator switches or a digital add-on.

The function generators follow the trajectory of the set values, that is, they interpolate between the set values: for each value Y, the output Y_a compares its computed value with the set stored value Y_a0. The Funktion-gebereinstellung (function generator setting) translates this through the analog setting elements.

Figure 37 — Function-generator setting procedure

[page 54]

The following steps are carried out in their chronological sequence as listed below (or according to a table or curve):

In the list of table entries x enters a Value or Table at n steps, where Δx₁, Δx₂, …, Δxₙ = n+1 steps, representing the corresponding y-values y₁, y₂, …, yₙ₊₁.
Press socket “D/M” at the Bedieneinheit (operating panel), the “Buchse Messe” (measure socket), the “Einzel” (single) socket, and the “Ablesenz” − K socket.
Press “Pause” on Netzschalter.
Drücken (depress) the Buchse “D/M” on the Bedieneinheit and check whether the Buchse Messe, “Einzel,” and the individual Potentiometer switches position themselves for the required Funktionsgeberseinstellung (function-generator setting).
Switch the “D/M” switch to set the output of the Speicherpotentiometer into position “D” (operation mode) position “D,” then switch “Einzel” to position “K”: a. Upon switching the Digitalzusatz “D” at Position 20 of the function generator set to obtain: Trigger the function generator outputs initially, which drives the function-generator signal for each subsequent step of Δx to the computing element. b. For each Δx value, compute the function-generator output according to the set Potentiometer-coefficient values.
Press the Buchse “D/M” so that the Digitalzusatz functions hold their set values (mode “D”), and then: a. The function generator follows this sequence:
- y₁ → y₂ → y₃ → … → yₙ₊₁
Drücken the Buchse 20 des Speicherpotentiometers to the “D” setting, i.e., set the output from Position 20 of the function generator hold to “operate,” giving:
- Output Y_a corresponds to the set y-function value.
Verify the Buchse D/M outputs for positions 31 and 13: a. Check that each position follows: y₁ at Δx₁, y₂ at Δx₂, …, yₙ at Δxₙ, yₙ₊₁.
a. The Potentiometereinstellung P confirms the output from the function-generator setting:
- y₁ at the first x-value, P set. b. Then, the result corresponds to the set values is confirmed: y₁, y₂, …, yₙ₊₁ match the respective x-values.
Drücken Buchse 20 (Speicherpotentiometer’s function generator: Digitalzusatz set to “D” on Position 20): a. At any Buchse x = x₁ → the set value at position P becomes: Y_a = y₁; at x = x₂ → Y_a = y₂, and so on for all values T₁, T₂, …, Tₙ.

2.3.2.5. Populating and Programming the Function Boards

The plug-in unit positions for the various functions can be set according to the tables in the function board. The right-hand part of the tables is subdivided in the same way as the function boards accessible from the rear of the computer. In those tables, each individual plug-in unit type always appears as a single plug-in unit entry. On the free positions, both plug-in-type units as well as complete sets of a different kind may be inserted. The hatched positions in those tables may not, however, be occupied. Completely outside hatched positions may be used to program various functions.

Table 6 “Variable Functions” differs somewhat in structure from Table 5 above. In place of the designation of the individual functions, a symbolic characterization of the line elements of the generated polygonal stretches is given here. The large arrows indicate the direction of the slope and the more finely drawn numbers indicate the number of individual line segments. The crossing small arrows indicate any adjustability of the first knee-point in the horizontal direction of the ordinate values, the double arrow indicating a displacement of ±10 V, and the single arrow indicating adjustability of the first knee-point between 0 and ±10 V. Adjustability of the remaining knee-points is always between 0 and −10 V.

Table 6 contains example configurations. Programming a desired function requires knowledge of the characteristics of the plug-in units of types VAR 111 (VAR1A), VAR 211 (VAR2A), VAR 141 (VAR1D), VAR 241 (VAR2D), VAR 121 (VAR1B), VAR 221 (VAR2B), VAR 131 (VAR1C), VAR 231 (VAR2C), as described in Section 1.4.2.5, together with the schematic from Fig. 47 to Fig. 50. Depending on the type used, 2 plug-in units (Fig. 49) or up to 4 plug-in units (Fig. 50) are required.

Note that the potentiometers “−1”, “−2”, etc. on the function generators must now be set accordingly.

To achieve the greatest possible accuracy, all settings in the specified sequence should be repeated (possibly several times).

[page 56: figure only — Fig. 38 shows the socket field of a function board; Fig. 39 shows plug-in units of type VAR 1 … (Series VAR 100); Fig. 40 shows plug-in units of type VAR 2 … (Series VAR 200). In Fig. 38 the connection sockets of a function board are labeled on the programming field. These labels reappear in the programming circuit diagrams as orientation.]

TABLE 5

Fixed Functions

Designation	Formulation	Populating the Board Positions				Circuit (Fig. No.)
		Right			Left
		y	x	y	x
		Plug-in units (typ.)		Plug-in units (typ.)
Parabola multiplier SPM 134	x·y	FM 3B, FM 3A, FM 3B, FM 3A				41
Parabola multiplier SPM 142	x·y		FM 4B, FM 4A			41
Squarer SQF 112	+x²	FM 3B (hatched)		FM 3B		42
Squarer SQF 122	−x²		FM 3A	FM 3A		43
Sine function SSF 112	sin(π/2·x)	SIN 1B, SIN 1A				44
Sine function SSF 122	sin π·x	SIN 2B, SIN 2A				44
Sine function SCF 112	cos(π/2·x)	COS 1B, COS 1A				44
Sine function SCF 122	cos π·x	COS 2B, COS 2A				44
Arc-sine function SAF 112	(1/2)·arc sin x	ARC 1C, ARC 1A				45
Logarithm function ALF 111	−(1/2)·lg 100·x		LGS 1A			46

Memory networks

| | ASN 742 | (hatched) | A-SN 1 | | | | 51 |

Comparator switches

| Electronic | ASE 741 | (hatched) | A-KS 8 | | | | 52 | | Electromechanical | ASM 741 | (hatched) | A-KS 3 | | | | 52 | | Noise generator RGF 104 — Output at socket Gx of the function board | | | RG 12a | | | | |

TABLE 6

Variable Functions

Number of segments, slope direction and adjustability*	Plug-in units								Circuit (Fig. No.)
	VAR	VAR	VAR	VAR	VAR	VAR	VAR	VAR
5 segments, positive slope	111								47
5 segments, positive slope + 8 knee-pts	211	111							47
5 segments, negative slope	←B (hatched)								48
6 segments, positive slope + 5 seg. neg. slope	231	131							48
5 segments, positive slope	141	(hatched)							47
6 segments, neg. slope + 5 seg. pos. slope	241	141							47
5 segments, neg. slope	(hatched)	121							48
→←neg. + 5 neg. slope	221	121							48
6 →← + 5 neg. slope	231	111							49
6 neg. + 5 neg. slope	211	131							49
6 neg. + 5 pos. slope	241	111							47
5 segments, pos. + 8 neg. slope	141	211							47
6 →←+ 5 neg. slope	221	111							49
6 neg.+ 5 neg. slope	211	121							49
6 neg.+ 5 neg. slope	241	131							49
6 →← neg. slope	231	141							49

(continued on next page)

[page 54: continuation of Table 6 (Variable Functions) with additional rows, plus legend and Table 7]

The table continues with additional combinations of segments and slope directions. The legend explains:

The integer on the left of an arrow = number of line segments generated by one plug-in unit
Arrows with slope direction = direction of slope of the polygon segments generated by each plug-in unit
↕ = ordinate displacement between +10 V and −10 V (first knee-point fixed at 0 V)
← → = adjustability of the first knee-point between 0 and +10 V
→ = adjustability of the first knee-point between 0 and −10 V

Table 7 — Properties of plug-in units with variable functions

Type	VAR 111	VAR 121	VAR 131	VAR 141	VAR 221	VAR 221	VAR 231	VAR 241
Number of line segments	5	5	5	5	6	6	6	6
Adjustability of function in ordinate direction	adjustable between +10 V and −10 V				adjustable between +10 V and −10 V
Position of the 1st knee-point	0 V				adjustable between 0 V and +10 V / −10 V
Position of the remaining knee-points	adjustable between 0 V and +10 V / −10 V / −10 V				adjustable between 0 V and +10 V / +10 V / −10 V / −10 V
(diagram of knee-point shapes)

[page 55: figure only]

Fig. 41 — Parabola multiplier SPM 134 and SPM 142: X and Y inputs feed into a function board block G_XY via sign-inverter amplifiers, with a gain-10 amplifier producing output +X·Y.

Fig. 42 — Squarer SQF 112: X input feeds into function board block G_1X (with +X, −X, +Y, −Y connections), with gain-10 amplifier producing +x².

Fig. 43 — Squarer SQF 122: Same configuration as SQF 112, producing −x².

Fig. 44 — Sine functions SSF 112 and SSF 122 and SCF 112 and SCF 122: X input feeds via function board G_1X into a gain-10 amplifier, producing outputs: sin(π/2·X), sin(π·X), cos(π/2·X), cos(π·X).

Fig. 45 — Arc-sine function SAF 112: +X input feeds via G_1X into a gain-1 amplifier, producing +arc sin X.

[page 56: figure only]

Fig. 46 — Logarithm function ALF 111: +X₁ and +X₂ inputs feed into function board blocks G₁ and G_X via an inverter. Two gain-10 amplifiers produce outputs −1/2·lg 100·X₁ and +1/2·lg 100·X₂.

Fig. 47 — Variable function VAR 111 (211) and VAR 141 (241): +X feeds via an inverter into function board block G_1X; the output of the function shaper S has a maximum slope of 3 V/V; an optional gain-10 amplifier stage produces an output with maximum slope of 0.3 V/V. (The dashed block is optional.)

Fig. 48 — Variable function VAR 121 (221) and VAR 131 (231): +X feeds directly into function board block G_1X; the function shaper S output has maximum slope 3 V/V; the optional gain-10 stage gives maximum slope 0.3 V/V.

[page 57: figure only]

Fig. 49 — Variable function from 2 plug-in units: +X feeds via an inverter and function board block G_1X into the function shaper S, producing f(x).

Fig. 50 — Variable function from 4 plug-in units: +X feeds via an inverter into function board blocks G₁ and G_X, with additional blocks G_2Y; the function shaper S produces f(x).

Fig. 51 — Memory network ASN 742: Circuit diagram showing X and Y inputs each feeding through 1 kΩ resistors and 0.05 µF capacitors into gain amplifiers G_x and G_y, with outputs X/(1+pT) and Y/(1+pT) respectively. Control signals (−X and −Y) are applied via inverter amplifiers.

Note: The input variable (+x or +y) is accepted when the control input (−x or −y socket) is at logic “0” and is held as soon as logic “1” appears.

[page 58: figure only]

Fig. 52 — Comparator switch ASE 741 / ASM 741:

Circuit shows X₁ and X₂ inputs feeding into a comparator block (with 10 V reference at top). Outputs U₁ and U₂ result from the comparator state. The switch positions are:

x = U₁ when (x₁ + x₂) ≥ 0
x = U₂ when (x₁ + x₂) < 0

The switches can be controlled by any binary signal from the computer or from the digital attachment DEX 102.

2.4. Operating Mode Selection

The operating modes are selected by pressing the appropriately labeled illuminated pushbuttons on the control panel. In the operating modes Single Computation, Repetitive Computation, and Computation with Hold, the computation time can be set simultaneously, as described below.

Setting the Computation Time

The computation time is set by a combined setting of the rotary switch and the precision potentiometer at the control panel. The scale of the rotary switch for computation time shows in its upper half the range within which the precision potentiometer can set the computation time. In this way, for example, all computation times between 0.01 and 0.1 sec. can be set (more precisely: between 0.01 and 0.11 sec., since there is a ten-percent overlap for adjacent ranges). Together, the 4 ranges allow a continuous setting of computation times between 0.01 and 110 sec. The lower half of the scale indicates that two successive pause times from the ranges 0.01, 0.1, and 1 sec. are assigned. For the two intermediate ranges, 0.1 to 1 sec. and 1 to 10 sec., this provides a choice of two different pause times. The integration factors used in the computation should be assigned as follows:

Integration factor	1 (5 µF)	1 sec. minimum pause time
Integration factor	10 (0.5 µF)	0.1 sec. minimum pause time
Integration factor	100 (0.05 µF)	0.01 sec. minimum pause time

If needed, the pause time between two repetitive runs does not need to allow the exact entry of an initial value.

2.4.1. Pause

Press the “Pause” button.

The operating mode Pause is essentially the initial state of all computing operations. Upon pressing the button, any currently running computation is interrupted and the integrators again take on their original initial values. Socket “Po” has the same effect, but the previously computed result remains stored in the computer in Pause mode.

The switching-on of the computer and programming may only be performed in the Pause operating mode.

2.4.2. Single Computation

Set computation time.
Press button “weiter −1 x” (“advance −1 x”).

The computation sequence Pause–Computation–Hold runs only once. Single computation is preferably used prior to oscilloscope display or to use of an XY recorder as an output device. After a single computation run, further computation is also possible via button “Re” or the photo-socket can be activated.

2.4.3. Repetitive Computation

Set computation and pause time.
Press button “Rep.-Rechnen” (“Repetitive Computation”).
End or interrupt the computation cycles by pressing the “Pause” or “Hold” button.

2.4.4. Computation with Hold

Set computation time.
Press button “mit Halt” (“with Hold”).

In this operating mode the computer runs with the computation time set by the timer, proceeding step by step into the Hold state. All computed values remain stored. This state is indicated by the illumination of the Hold indicator lamp.

By pressing the “weiter −1x” button, also via socket “Re” or the photo-socket, the computation can be continued or restarted for the same or a longer time up to the next Hold state. In this way, point-by-point tracing of a curve, or approaching a desired value, is possible.

2.4.5. Continuous Computation

Press button “Dauerrechnen” (“Continuous Computation”).
End or interrupt the computation by pressing the “Pause” or “Hold” button.

During the operating mode Continuous Computation, the timer runs repetitively and continuously applies the set control signals to the sockets T_Repet, T_Repet and T_x, as well as the time-base voltage to socket “Z” for display.

2.4.6. Hold

This mode allows arbitrary interruption of any computation process at any time. All network voltages remain held until the computation is resumed by pressing one of the three computation buttons, or until the computation is terminated by pressing the “Pause” button. The “Po” button has the same effect.

2.4.7. Setting Potentiometers (Button “Pot.”)

By pressing the Pot. button, all coefficient potentiometers are prepared for setting. At potentiometer readout (see 2.5.), the potentiometer setting corresponding to the readout can be made.

2.4.8. Static Testing

The Static Testing operating mode enables the testing of computing circuits for correct programming and correct coefficient setting by measuring steady-state values and comparing them with previously calculated discrete solutions.

To perform a static test on a normal computing circuit, the following measures are required:

Press button “stat. Prüf.” (“static test”).
Test signals that are to appear at the output sockets of the integrators should be connected either directly via the “P”-sockets of the integrators or via the potentiometer sockets. For loading reasons, care should be taken that when using a potentiometer to generate the test signal, the connection is not made in the usual way. Instead, it is preferable to perform the Static Test by connecting the measuring socket “M” of the relevant integrator directly to the measuring instrument “M” or the digital voltmeter. Such patched connections can also be maintained during the subsequent computation.
Via the amplifier summation-system, form the sum of the input quantities at all used amplifiers for the chosen static values, and compare with the theoretically calculated values.

Note: When integrators are used, this sum multiplied by 1/10 appears at the amplifier output. It is not available at the summing junction socket, but only at the amplifier output socket.

2.4.9. Null Balancing of Computing Amplifiers

Switch all switchable amplifiers to summer mode (U11, U12, U21, U22).
Press button “Null” on the control panel.
Null-point measuring amplifier to zero: Press the Null button for the measuring amplifier in the upper module slot, simultaneously set the appropriate null potentiometer, and bring the reading of the measuring instrument to 0.
Perform the null balance by pressing the associated button for each switchable amplifier, simultaneously setting the associated null potentiometer display to zero. The null balance should be performed no earlier than about one hour after switching on the computer.

2.5. Selection

All computing amplifiers and coefficient potentiometers can be individually selected directly via their associated pushbuttons. The pushbuttons of the computing amplifiers serve simultaneously as illuminated indicators of their state.

On each module slot, all four selected computing amplifiers are present with corresponding identification. The selection of function generator outputs is made by pressing the Function Generator 1 button with key U11; for Function Generator 2 via key U21. At the middle module slot (Function Generator 2, key U21), in addition to the output of the function generator network, two inverting amplifiers are available, selected by keys U11 and U12 respectively, and two non-inverting amplifiers selected by U21 and U22 respectively.

Each selection switches the computing amplifier output to the following devices:

Voltage meter in the upper module slot:

Both positive and negative voltages in the range +15 V to −15 V are indicated; a fast-responding instrument allows a quick overview of the output voltages occurring.

Compensation measuring device:

For precise measurement of output voltages in connection with the null instrument and the precision potentiometer in the lower module slot.

DVM line:

For connected digital voltmeters.

Socket “VA” on the rear of the upper module slot for connection to recorders or other external devices.

The selection of the nineteen coefficient potentiometers is made via the directly associated illuminated buttons. Each selection in the operating mode “Potentiometer Setting” triggers the potentiometer slider on the potentiometer dial in the upper module slot (see also 2.3.2.2.), but not, however, in Static Testing.

2.6. Measuring with the Compensation Measuring Device

Connect socket “DVM” with “Komp.-Meas.” via a short-circuit cable.
Measure the voltage to be measured either directly via socket “M” or via the selection system of the amplifiers and input it via the lower module slot.
Enter the amount and sign of the voltage to be measured on the scale of the precision potentiometer, or alternatively read off the illuminated sign indicator lamps.

2.7. Automatic Hold on Overload

If during a computation a computing amplifier saturates or overloads, the computed result becomes distorted and further computation is mostly meaningless. For this case, the automatic Hold is provided.

The automatic Hold is activated by pressing the button “Ü-Halt” (“overload hold”). The computation is then halted at every overload of any computing amplifier. The computing voltages remain held and the overload is indicated by the illumination of the overload indicator lamp of the affected amplifier. The switching-on of the automatic Hold is indicated by the illumination of the “Ü-Halt” button. After the cause of overload has been eliminated, the computation can be restarted by pressing the Pause button. The started computation can also be continued, if the “Ü-Halt” button is released, thereby disabling the overload-hold automatic.

2.8. Oscilloscope Display of Computation Results

Connect the output of the computing circuit to the measuring inputs of the oscilloscope, either directly or via socket “VA”.
Take the time-base voltage from the timer via socket “Z” if required.
Set the oscilloscope to the desired deflection frequency.
For further connection of oscilloscopes to the computer, see 2.1.2.

2.9. Photographing Oscillograms

Connect the photo socket of the control panel with the flash contact of the camera.
Set the camera to an exposure time corresponding to one computation period.
Press the button “weiter −1 x”, let the computation run.
Release the camera.

The computation runs in the same way as when pressing the button “weiter −1 x”.

2.10. Recording via X-Y Recorder

Recording of computation results is performed analogously to the oscilloscope display (see 2.8.). For connection of the recorder, see 2.1.2.

2.11. Measuring with Digital Voltmeter

See points 2.1.2. (connection of output devices) and 2.5. (selection).

3. MAINTENANCE

The functional tests described below are to be performed at the first commissioning and repeated periodically thereafter.

3.1. Testing Indicator and Control Lamps

Switch the computer on and off repeatedly. All indicator lamps of the overload automatic and the lamps of the buttons “Netz” (+10 V and −10 V) must illuminate briefly simultaneously. The indicator lamp of the button “Netz” in the switch-on state of the computer must be permanently illuminated.
Press all nine buttons of the operating mode selector on the control panel as well as the buttons “Ü-Halt” and “Extern” in sequence. During respectively the buttons that are pressed, all indicator lamps of the control panel must illuminate. Exception: the buttons “Pause”, “Hold”, and all computation buttons, which show the momentary computation state, are excepted.

3.2. Testing the Power Supply

Test with the voltage values labeled on the test points of the power supply unit one after the other. The measuring instrument must show the corresponding voltages.

3.3. Testing the Computing Amplifiers

3.3.1. Null Balance

See 2.4.9.

3.3.2. Testing the Gain Factor of the Summers

Leave the switchable amplifiers in summer configuration.
Press button “Pause”.
Connect the machine unit −E (−10 V) from a red socket via conductor “1” to the measuring input of the amplifiers to be tested.
Press the associated button for the amplifier to be tested.
Measure the amplifier output voltage (using a digital voltmeter).

The difference from 10 V must not be greater than 4 mV.

3.3.3. Testing the Integrators

Switch the switchable amplifiers to integrator mode.
Set the rotary switch and potentiometer to a computation time of 1 sec.
Connect the machine unit −E (−10 V) from a blue socket with an input “1” of an inverting amplifier and connect the output of this amplifier to the measuring input of the integrators.
Switch “mit Halt” (“with Hold”).
As soon as the computation state “Halt” is reached, the affected amplifiers must illuminate; the lights on the left side of the function board must not illuminate.
The Funktionsgeber switch (Schalter 20) with the input “1” of an inverting amplifier and the output of this amplifier to the Eingangsbuchse (input socket) of the Funktionsgeber to be connected; ordinate must be adjustable from −10 V to +10 V.

Continue with Potentiometer “0” until the output voltage of the Funktionsgeber is exactly 0, using the compensation measuring device or a digital voltmeter.

Set the Einstellgerät (Schalter S 21, Umschalter 20) to −10 V.
Turn Drehschalter 20 by one position.

By advancing Potentiometer “+1” up to the stop, the maximum slope can be set. Coarse readout of the slope at the upper module slot in the normal voltage meter mode, precise readout using the null instrument of the compensation measurement or digital voltmeter.

With Potentiometer “+1”, set the output voltage of the Funktionsgeber to 0. For all other Potentiometer values from “−2” to “−10”, do the same accordingly.

Set the Schalter des Einstellgerätes to +10 V.
As in steps 6., set the Funktionsgeber-Potentiometer “−1” to “−10”.
Set the Schalter des Einstellgerätes to “0” again.

3.3.5. Testing the Multipliers

Connect the output of the memory network with the dark-green summing junction socket “S” of the associated amplifiers.
Press button “Pause”.
Perform the multiplication 0 × 1 = 0 as follows:
- Apply machine voltage −E to socket “+x”.
- Apply machine voltage −E to socket “−x”.
- Connect sockets “+x” and “+x” with the computing sockets and press the select button of the multiplier follow-up amplifiers.
The deviation from null must not be more than 10 mV, corresponding to a null instrument reading of about 1 scale division with compensation measurement.
Perform the multiplication 1 × 0 = 0 as follows:
- Apply machine voltage −E to socket “+y”.
- Apply machine voltage −E to socket “−x”.
- Connect sockets “+y” and “+y” with the computing sockets and press the select button of the multiplier follow-up amplifiers.
The tolerance for deviations from null is the same as under point 3.
Perform the multiplication 1 × 1 = 1 as follows:
- Apply machine voltage −E to both sockets “+x” and “+y”.
- Apply machine voltage −E to socket “−x”.
- Press the select button of the multiplier follow-up amplifiers.
The deviation of the output voltage from 10 V must be smaller than 20 mV, corresponding to about 2 scale divisions with compensation measurement.
Perform the remaining multiplications from steps 3. to 5. with the other multipliers.

3.3.6. Testing the Coefficient Potentiometers

Press button “Pot.”.
Check each potentiometer by compensation measurement or digital voltmeter whether it can be set to zero. (The endpoint potentiometers must be connected to the computer for this purpose.)

4. COMMISSIONING

4.1. Fault Detection

If the computer despite correct operation yields no obviously correct results, then the functional tests described in Section 3 are first to be performed.

If these tests yield no success, or if the fault involves the replacement of plug-in units, the service department should be called upon.

4.2. Fault Localization

In general, the fault is clearly identified as soon as the faulty symptom is correctly recognized. Otherwise it may be a matter of a fault in the power supply voltage. Specific fault localization is as follows:

4.2.1. Failure of Operating Voltage

First check the relay voltage, 400 Hz voltage, and lamp voltage at the rear of the power supply unit; check whether a fuse is blown. Fault is shown by illumination of a lamp in the fuse holder of the power supply unit. If the voltages are in order, handle the faults as described in Sections 4.3. and 4 (pp. 55.3048.100 = 00 BSP) by making the following connections:

Socket 4, b4 — Socket 3, c9: Socket 4, b4 — Socket 3, c9

Use two 30-pin Siemens buses (the accessory set contains these), prepared accordingly and inserted with the module pulled out on Socket 3 and Socket 4.

Before the pulled-out module is connected to the mains again for testing, make sure that the bridges have been removed and that the centrally routed earth point on the rear is firmly connected.

Warning: After connecting the built-in module to the mains, the VDE regulation forbids touching the front panel while it is being inserted. When inserting and removing

[page 73]

Steckeinheiten must be pushed in until the Panto-spring catch engages. In the case of a fault, the voltage setting must first be checked.

1. Malfunctions during the measurement of the Netzgerät (power supply) output voltages.

Note: During the measurement of the output voltages (see p. 14/15 and p. 3 ref.), the specific voltages listed must be verified.

a) Specified voltage is present: fault lies with another plug-in unit.

Fault location in the outgoing Einschub, see Section 2 and 3.

b) Specified voltage not present: Einschub to be replaced.

Service requests another Einschub to be inserted.

Fault lies in the preparation of the Einschub, replace accordingly.

c) Measured-value of the Netzgerät (power-supply) electronic control unit (Regeleinheit) cannot be found. Fault also appears in other units by means of identical Steckeinheiten and with common housing.

Fault probably in the Netzgerät, service to be called.

Fault location in a single separate Einschub, see Section 2 and 3.

d) Incorrect voltage supplied to the Einschub: fault lies within the Einschub.

Fault location in Einschub, see Section 2 and 3.

2. Malfunctions while evaluating the outgoing Einschub pulses against the Netzgerät.

Service requests another Einschub be inserted in the work unit.

If an outgoing Einschub and voltage are present (see Section 4.3.3.):

a) Specified voltage not present: fault lies in the Einschub.

Fault location, see Section 2 and 3.

b) Specified voltage present: fault not with this Einschub.

Fault lies in the connecting cable or in the unit, see Section 4.3.2.

If an outgoing Einschub and voltage are not present (see Section 4.3.3.):

a) Specified voltage not present: fault lies in the Einschub.

Fault lies in the following Einschub: see Section 2 and 3.

b) Specified voltage present: fault not with this Einschub.

[page 74]

b) Specified voltage present: fault lies with the incorrectly programmed Funktionsgeber.

Fault lies in the other Einschub, see Section 8.

c) Malfunction in the single Einschub that is not the fault of the defective Einschub. Fault thereby arises every time the Einschub is changed. However, it is possible to assess the fault by the replacement of two separately measured Steckeinheiten.

Fault lies in the Verbindung (connection) of the Einschub.

Fault found in this Steckeinheit using only simple Steckeinheit comparison is always checked and judged accordingly.

4.2.2. Fault-finding in the 400-Hz supply

Oberen Einschub verify (Section 4.3.2.), to see that no “Netz” (mains) signal is present. Set the Netz amplifier and type “Netz” switch.

a) 400-Hz Spannung not present:

Fault lies in the Gesellschaftsleitung (main lead), see Section 2 and 3, verified.

b) 400-Hz Spannung present: fault lies in the Steckeinheit.

Fault lies in the Gesellschaftsleitung only to the existing Einschub.

Fault lies in the next Einschub, see Section 2 and 3.
Malfunctions in Chopper (Ch 750) and 400-Hz-Verstärker (H-H-C) of the Netzgerät Spannung:

a) 400-Hz Spannung N/C verified.

Fault lies in Verbindung (connection) of the above Einschub, see Section 2.

b) The 400-Hz Spannung in each of the Zahlern also becomes Chopper and Milliverstärker when confirmed.

Fault lies in the Einschub: if defect and malfunction are both present, see Section 2.
Malfunctions in Generator-Steckeinheit (GE 3A, 400-Hz-Verstärker H-GE2) in the Abstimmungsblock and Spannungsgerät H-GE2 of the Netzgerät:

a) 400-Hz Spannung N/C verified.

b) The Fault lies in the Verbindung and in the above Einschub. Service requests another Einschub be inserted in the work unit.

If 2 or more H-GE2 have a defect and are still in the unit, fault lies definitively with the Einschub: Netzgerät-Steckeinheit GE 3A; H-GE 2 or similar H-GE2 is defectively in the Einschub between fault.

[page 75]

Oberen Einschub verified (p. 4.3.2.), to see that the Netz-Ausgangsspannung is delivered to and Type “Netz” is set.

a) 400-Hz Spannung N/C verified.

Fault lies in the Gesellschaftsleitung also to the single Einschub, see Section 2 and 3.

b) Nacheinander the Chopper (Ch 750) and 400-Hz-Milliverstärker (H-H-C) of the Netzgerät Spannung verified.

a) 400-Hz Spannung N/C verified.
```
  Fault lies in Verbindung to the above Einschub. Service requests another Einschub be inserted in the work unit.
```
b) The 400-Hz Spannung in each of the Zahlern also becomes Chopper or Milliverstärker when confirmed.
```
  Fault lies in the Einschub: defect and malfunction are both present, see Section 2.
```
c) Nacheinander the Chopper (Ch 750) and 400-Hz-Milliverstärker (H-H-C) of the individual Einschub Spannung verified.

a) 400-Hz Spannung N/C verified.
```
  Fault lies in Verbindung to the following Einschub. Service requests another Einschub be inserted in the work unit.
```
b) The 400-Hz Spannung in each of the Zahlern also becomes Chopper and Milliverstärker confirmed.
```
  Fault lies in the Einschub: if defect is confirmed, see Section 2.

  The current is defect and will not engage.
```

4.3. Maintenance

4.3.1. Auswasch-Arbeiten (Cleaning tasks)

Note: The plug-in card capacitors (lamps) must be checked and confirmed for function. The capacitor probe and test cards of the unit must be checked and maintained.

The caps of the circuit — probe and test cards — can be removed by hand or using a tool and replaced with new ones.

[page 76]

4.3.2. Fuses (Sicherungen) in the Netzgerät

For purposes of ensuring the regular functioning of the compute unit, the fuse values given here must be strictly observed. The fuse values are stated as amp ratings (milliamperes or amperes). A new replacement fuse must always be verified to be rated correctly before installing.

Fuse current ratings of the Netzgerät (mains supply):

110 V oder 130 V: 1.8 A (träge/slow)
220 V oder 240 V: 0.8 A (träge/slow)
400 Hz: 12 A (träge/slow)
4 V: 2.5 A (träge/slow)

At increased mains voltages the fuse must be installed as follows. In the event of a fault in the Netzgerät the individual fuse settings (values) will be checked.

Note: Fuse amperage values (in brackets) are not verified.

4.3.3. Assembly and Removal of Steckeinheiten (plug-in units)

a) Ausbau (Removal)

Netzstecker (power plug) pull out and the lid open.
Rechner-Netzschalter (computer main switch) switch off.
Move the Einschub lock to the outside.
Steckeinheiten at the front of the respective Einschub (plug-in unit) removed.
The Einschub is pulled from the exterior of the Potentiometerfeld (potentiometer field).

Note: When pulling out the exterior Einschub, the Funktionsgeber (function-generator) unit must first be checked in the exterior Einschub. There must be no resistance in the plug; each external pull-out of each Steckeinheit must hold the unit together properly if it is to be fully pulled out.

[page 77 — figure only with labels]

b) Einbau (Installation)

Einschub is pushed in from the front.

Before installing the Potentiometerfeld (potentiometer field), the Funktionsgeber-Einschub must first be installed.
Einschub is screwed to its front panel with the rack.
Connect the Anschluss- and Verbindungskabel (connection cables) in the arrangement shown in Figure 31 using the designated connection strips provided.
Close the rear door of the computer.
Connect the Netzanschlusskabel (mains cable) to the mains socket of the computer and connect with the Netzsteckdose.

Warning: Installation and removal of plug-in units must not be carried out while the chassis is under voltage (live).

[Figure 53: Montageinheit Netzgerät (power supply assembly unit) — module layout diagram showing:

Left sub-rack: H-GE 3 (400 Hz Verstärker), H-GR 2 (25/15 V), GE 3A (400 Hz Generator), H-KS 1 (Kühlkarte), H-KE 1 (Komparator), HA-1C (Hauptverstärker), HI-1C (Hilfsverstärker), A-ZS1 (Zeitgebersteuer.), H-MV1 (Messverstärker)
Right sub-rack (Siebungseinheit / filter unit): H-KS1 (Kühlkarte), H-GR1 (−15 V), H-GR1 (+15 V), H-GR1 (+30 V), NS 7A (−10 V), KV 1C (Verst.), NS 6B (+10 V), KV 1C (Verst.)]

[page 78 — figure only with labels]

[Figure 54: Montageinheit Rechnerverstärker (computer amplifier assembly unit) — table/grid diagram showing the layout of multiple HA 1C and HI 1C amplifier cards across several rows and columns, with Ch 760, Ch 760/70 designations, along with numerical row labels 1–16 visible.]

Notes:

a) For the plug-in unit in question, see Section 4.3.3.1 through 4.3.3.2 as described above.

Note: When replacing the Rechnerverstärker-Steckeinheiten (computer amplifier plug-in units) and in the Potentialfeld (potential field), one each of the Hauptverstärker (HA 1C) and Hilfsverstärker (HI 1C) card must be inserted together. No short-circuit resistance is present. The resistance values for the Steckeinheiten must be stated and verified when both of them are being removed.

[page 79]

b) Einbau (Installation)

Steckeinheit nach Bestückungsplan des Einschubs (Figures 53 to 56) at the same position in the Montageplatz (mounting position) of the rack as a common group assembled. In the Bestückungsplan the same position within the Steckeinheit will show the same marking from the Vielfachstecker (multi-pin connector) and on the same Steckleiste. The same position must be identical in all Steckeinheiten. No resistance is present. Both resistance values and the Steckeinheiten sizes must be stated and verified.
Einschub is pushed into the unit, see Section 4.3.3.6 through 10.

[Figure 55: Normungseinheit Funktionsgeber (function generator assembly unit) — diagram showing two Funktionsgeber 1 and Funktionsgeber 2 sub-racks with rows labeled Ps 1, Ps 2, 1/V2, HA 1C, HA 1C, PS 5B, PS 5B, PS 3B, PS 3B, and similar components across 8 rows, with columns labeled Einschub 1 through Einschub 2 and row labels 1–8 numbered.]

[page 80 — figure only with labels]

[Figure 56: Magazin im Unteren Einschub (magazine in the lower plug-in unit) — layout diagram of the RA 253 bottom chassis showing the following cards stacked top to bottom:

H-KE1/H-KM1
H-KE1/H-KM1
HA 1C } row 1a
HI 1C }
HA 1C } row 1c
HI 1C }
HA 1C } row 1d
HI 1C }
HA 1C } row 1e
HI 1C }
PM 3B }
PM 3A } row 1f
PM 3B }
PM 3A }
PM 3B }
PM 3A } row 2a
PM 3B }
PM 3A }
PM 3B }
PM 3A } row 3a
PM 3B }
PM 3A }
PM 3B }
PM 3A } row 4a
PM 3B }
PM 3A }
PM 3B }
PM 3A } row 5a
PM 3B }
PM 3A }
H-SL1
H-SL2]

[page 81 — figure only with labels]

[Figure 57: Anordnung der Relais hinter dem Programmierfeld (arrangement of relays behind the programming panel) — block diagram showing relay positions labeled U, Ps, U, U, Ps, Ps, U, U, Ps, U, U and Prüf (test) rows with associated annotation.]

[Figure 58: Anordnung der Relais im Bediengerät (arrangement of relays in the operator/control unit) — block diagram showing:

Row 1: Rs 5 (Extern), Rs 4 (Repet. Rechnen), Rs 3 (Autom. Vorzeichnen), Rs 2 (Rechnenstört verzögert), Rs 1 (Rechnenstört)
Row 2: Rs 10 (Dauerrechnen), Rs 9 (Dauerrechnen), Rs 8 (1× Rechnen), Rs 7 (Rechnen m. Halt)
Row 3 (bottom): Rs 15 (Rechen-Relais), Rs 14 (Pause), Rs 13 (stat. Prüf.), Rs 12 (Nullen), Rs 11 (Pot. Einstell.)
Note: The relays Rs 20 and 21 are positioned before connector 10, relay Rs 22 is before connector 5.]

[page 82]

5. STROMLAUFBESCHREIBUNGEN (Circuit Descriptions)

(see Figures 59 to 91 and Plan 2 a/b)

5.1. Bediengerät (Operator/Control Unit)

The control unit contains all the switches required for computer operation. It comprises a frequently needed timer for position detection, the complete voltage measuring instrument or the service monitor, and any desired measuring instrument (voltmeter) for presently selected use.

5.1.1. Betriebsarten-Wählschalter (Operating Mode Selector Switch)

The operating mode selector switch has two separate tensioner devices. Both devices can operate independently as individual tensioners and contain the operating modes “Halt” and “Ühalt” between the switches at buttons S0 to S15. All available operating modes are programmed using the buttons and switch positions (states) and the specific timing for all computing modes. The pre-selected operating timing and Table 8 shows corresponding timing parameters for the available operating modes.

Table 8 (Summary of relay states at the operator/control unit)

Description	Operation	Rechen (Compute)	Halt	Prüf. (Test)	Pause	Null
1 × rechen (1× compute)		1
N × rechen (N× compute)		1
Kanalwähler zu 1 (Channel selector to 1)
Anfangszustand (Initial state)
Einlesung des Widerstands-Integrierens (Initiation of resistance integration)

Note: Through “Ü” the tensioner relay “b” is actuated.

[page 83]

The minimum computing time results from the overlap of the computing states (the multi-stage timer). Die Faktoren für alle Betriebsarten (factors for all operating modes) correspond in their time ratio to the factors 3/7/4, 5/1 and 3 respectively. Rechnen includes at least 5 ms (14/5 and 1) per step.

5.1.2. Einzelsteuerung (Single control)

Through pressing the “Netz” (mains) button at relays Rs 5 and 21 momentarily, the Rechen-Halt-Funktion (compute-halt function) at step 3/7/4 is held. In the individual Einschub (plug-in unit), the Rechen-Funktion is via button S17 the upper Komparator-Funktion set. The Einzelsteuerung with relays Rs 4 and 21 maintains the individual step and the Zahlenfaktor (numeric factor). The upper timer position for the Komparator is 5/11/12 and the lower timer position is 3/12/13 simultaneously set and switched out with the counter. The timer states of relay Rs 4 and 5 therefore confirm the “Außerkraftleistung” (override) of the Zahlenfaktor.

5.1.3. Einzelsteuerung (Single control) [continued]

Through Drücken (pressing) the “Netz” button at relays Rs 5 and 21 momentarily, the Rechen-Halt-Funktion at step 3/7/4 is confirmed. The “Pause” relay, now “Halt” activated, operates and is controlled on both die Einschalt-Stellung (switch-on position) and die Schaltstellung Zeitgeber (timer switching position). The up/down position of the Netz-button S17 is confirmed by the Zahlenfaktor on die Kette Rs 5/11/12. The confirmed Rechen-Halt-Funktion through the digital Zeitgeber steps proceeds on the upper timer counter from S 18 to S18; then the lower timer counter to S 3/5/12.

5.1.4. Prüf. (Test) [mode]

Through Drücken (pressing) the button “Prüf.” the Rechen-Halt-Funktion at steps Rs 3/7, 4/5/13 is momentarily confirmed. The individual “Prüf.” mode position at Rs 3 is confirmed and sets this the lower relay position on Rs 5/13 to the step counter position verified. Now the lower position of the Prüf.-Relais Rs 3 maintains the Rechen-Halt-Funktion while the machine is locked out by the relay lock to the Stellung Rs 13. The single Rechen-Halt step 3/7 ends at Rs 13; the individual Rechen-steps 4/5 ends at Rs 13. The resulting step range is at S 3/5/12 and ends at Rs 5/13. A sequential step count at Rs 5/11/12 is also confirmed with the switch-out Zeitgeber.

[page 84]

5.1.5.1. 1× Rechnen (1× Compute)

The relevant computer mode activates several single stages together that match the mechanical step ranges for the lower position. It also drives 1× counter steps where the Komparator amplifier is at output 8 and 9 set accordingly. The Komparator at output 8 and 9 switches the digit field. The step in the digit field becomes position 1 (single position) at relay Rs 8. In the upper step of this relay state the Einzelfall (individual case) of the Komparator relay Rs 8 is activated. From the step-state of the Rechen-Relais 11/12, 22 the single-step count changes from the digit field position to the position 1 relay. This changes the step-counter the individual Rechnen (compute) relay to hold a stable state.

The following step-counter state allows from Rs 11/12 a sub-relay which is the Rechen-Relais counter at step 1 and 3 active and set at relay Komparator in order. Between the Arbeitsbereich (working range) at steps 4/5, 16 sub-relay actuation gives the Rechnen state and the result of this counting confirms the Zeitgeber counter. The Zeitgeber on the Einschub side is at all points the upper-count counter state.

In the computer at “Halt” the configuration of the control relay Rs 8 is confirmed. The configuration of the Rechen-Halt function keeps the relay Rs 8 confirmed. It must be noted that the individual Zeitgeber (timer-line counter) states allow digital steps from the count relay.

This then of the Arbeitsbereich (at steps 4, 5, 16) momentarily requires a Rechen-Halt-step sequence and establishes the step from the single Zeitgeber-Komparator relay states which also confirms the relay-positions H-S12 for the single Einschub.

[page 85]

In these states the single-count relay steps are output from each step count and the Rechen-Halt sequence at steps 11, 12, 13 and step 5/8 of relay Rs 1 is present; and thereby relay Rs 1 is present.

At the “Nullen” button the digital state steps, that is — after the Rechen-Halt — and begins with the “Pause” relay step. From relay Rs 12 the Zeitgeber step counter and via the relay state Rs 11, 22 the “Zeitgeber schlussstellt” (timer final position). Not Abfall (release) of the “Pause” result; and this then is the Ergebnis state “Zeitgeber schlussstellt” and confirms it on Rs 11, 12, 13 and 14 then the counter to “Pause” final relay — this “Pause” state that the relays Rs 11, 12, 13, and 14 maintain. The relay state of Rs 11 then switches the Betriebsart (operating mode) final state at Rs 14.

Table 9 (Summary of relay states in the control unit)

Rs 12	Further operation at computing, identification of the marking step position
Rs 13	Operating mode detection (Erkennung)
Rs 14	Operating mode detection with “Polling”-marking; drive of the “N-”-position Integrierens (integration initiation)
Rs 15	Position switching of one Betriebsarten (operating mode), and then the following Betriebsarten identification and configuration via Rs 11, 12, 13, and 14

[page 86]

Rs 12: Additional step counter for computing, identification of the mark step position.

Rs 13: Operating mode identification (Erkennung).

Rs 14: Operating mode identification with “Polling” mark; drive of the “N-”position-Integrierens.

Rs 15: Single control mode switching then following operating mode identification and configuring via Rs 11, 12, 13, and 14.

5.1.6. Potentiometereinstellung mit eingeschlossenem Schrittschalter (Potentiometer setting with enclosed step switch)

The potentiometer setting proceeds after the Buttons Rs 18 and Rs 17 are configured. Both the “Rechnen” (compute) and “Ühalt” (overrun halt) modes are programmed independently at the individual controls at buttons S0 to S22. The control mode activates at the Rechnen relay state and the individual steps in the following positions are set at the timing in the range S 7, 9 up to S 22. Positions S22 and S21, S22, 23 are configured for testing the integration ranges for “N-”-positions. The individual single Steckeinheiten step switches and testing of their step are: S 11, 12, 13, and 14.

5.1.7. Potentiometereinstellung mit eingeschlossenem Rechenschrittschalter (Potentiometer setting with enclosed compute step switch) 2.1.5.

Both buttons S 18 and S 17 are at the compute timing step relay Rechen confirmed. The timing “Rechnen” and “Halt” buttons are also confirmed at the Steckeinheit as an output. It drives the “Halt” relay to the controlled Potentiometereinstellung drive position in the direction of the Steckeinheit setting.

5.1.8. Zeitgeber (Timer)

As long as computing is performed (Rechnen), the following relay states detect the Integrierer available. The function of an Integrierer-Ausgangsspannung (integrator output voltage) of a normal value from 100 kΩ and the Up-Schalter (up-switch) to the Spannung (voltage) of this Integrierer is switched to the value and the starting position to a 100 kΩ. The input of the Integrierer is at a total of +10 V when this is switched in Relay “B”, and the starting input of the Integrierer at −10 V set. Schließlich (Finally), the “Integrierer-Ausgangs-spannung” of +10 V is reached, whereupon the total integrating Input-Spannung of −10 V is counted, which completes the “Schrittaufnahme” of the interval.

[page 87]

Komparatoren detect a little before the Polwechslung (polarity reversal) and the Ausgangsspannung (output voltage) of the Vergleichsverstärker (comparator amplifier). At S 4, 5, 5.9 the Rechnen-Relaiskette is checked and the Anfangssteuerung (initial control) is set at S 9, 13, 17. Positions S 11 and S 21 both are at the Rs 10, 12 and 400-Hz-Chopper (Ch 760) active and also with Milliverstärker-states. The Rechnen-Relaiskette state from S 9, 11 and 17 allows the digital count function.

The Komparator is also actuated from the S 17 output where the step “Halt” is in the “Null” relay state. Mode checking is confirmed at the Schaltstellungen (switch positions) Rs 9, 11, and 17. The mode final “Null” is checked through the drive S 19, 20 and allows the Schrittschalter-Kette (step switch chain).

This Komparator timing makes it possible for the timing step from “Rechnen” to “Halt” in the Rechen mode (between the Betriebsart states S 18 and S 20) to proceed such that a 5 seconds timing interval can be achieved. The timing step from S 19 to S 20 allows for a delay step of about 5 seconds. The computing is then done with the help of S 20 so that the delay-correction is also from the 5 second position.

5.1.9. Rechnen mit Halt (Compute with Halt)

Through pressing the “Repet. Rechnen” (repeat compute) button, the individual Rs 5 and Rs 6 computing relays together are momentarily held. The “Repeat-Rechnen” configuration therefore maintains in the Schaltstellung (switch position) Rs 9, 13 and 15 confirms, and the step-count is still at the Betriebsart switch state. The step count switch Rs 9 is at the mode step Halt/Null confirmed in the Betriebsart states for Rechnen. A “Pause” momentary step in the “Halt” mode will confirm the step delay Rs 5, 9 and for Dauerrechnen (continuous compute) also allows the mode state.

[page 88]

5.1.11. Dauerrechnen (Continuous Compute)

In the activated Zeitgeber, the step count result leads eventually to a simultaneous step count. The resulting step value is in the “I” positions 1 and 3 per Rechnen (compute) and there is the Anfangs-Abfall (initial release) Rs (I) 19/20. The step count switch Rs I (19, 20) allows for the i-Integration beginning check 8, 9/12, 15. And thereby the Zeitgeber (timer) switch operates the “Pause”-Relais.

A subsequent step-count delay via relays Rs (I) 9/15, 20 to the Zeitgeber-step count results in the Rs I (9, 13, 15, 20) combined timing output delay. The time of Zeitgeber (timer) at Rs (I) 9 to Rs I 13 confirms with the “Halt” at mode step Rs 8 in the first Integrationsanfang (integration start) timing position.

5.1.12. Stepschalten (Step compute)

Relais “Ü” (state I, positions 1, 3, 5, 9):

The “Ü”-Übertragung determines from positions I 5, 9 a subsequent (per-counter) single relay Abfall (release). The resulting step total from positions I 9/12, 15 to the Rs I 13 timing step confirms the simultaneous timing output. Since the “I” positions 1, 5, 9, 12 and 13 work together, the Rechnen “Übertrag” (carry-state) result is confirmed. The Rechnen carries are now obtained with relay Rs 11, 13 and active count confirms the “b”-state of the “Ü” relay.

5.1.13. Übertragungsmoment (Transfer/Carry moment)

As long as Rechnen (computing) is active, the following relay configurations detect Übersteuerungshalt (overdrive halt). The Re h-circuits (5.13) and the delay of the timer at button S 13 do not allow the individual Einschub removal or other devices in the workspace until the Rs 13 and Rs 22 relay is also reached in further steps.

[page 89]

[Figure 59: Stromlaufplan Überwachungsschaltung (circuit diagram of the monitoring/watchdog circuit) — schematic showing amplifier stage with potentiometer, Vergleichsverstärker (comparator amplifier), and Zeitgeberverstärker (timer amplifier) connections with component references B5, Rs 92, R5, and voltage levels marked.]

5.1.14. Potentiometersteuerung (Potentiometer Control)

Through pressing the “Null” button Rs 11 the following occurs:

In Rs 11/12, 13 the Schaltleiste is locked out by Sr 1 and then there is switching to the next Rechen state.
In Rs 11/12, 13 further Schaltleiste is blocked and the Potentiometerverstärker (potentiometer amplifier) is in its shut-off position.
The “B”-Schalterstellung (switch position B) at Rs 11/12, 16 results in the (intermediate) state “Ü” (overrun).
In Rs 11/13, 16 puts on the Stecker 3 (Connector 3) B the relay state.

The individual conductors of the Steckeinheit (plug-in unit) lead from there and relay Rs 5 gives via Sr 5, 16 the lock-out to Sr 5.

5.1.15. Nullen (Nulling/Zeroing)

The “Null” (zero) button: Rs 5 opens, interrupts the Haltekette (hold chain) for Rs 15 thereby ending every compute cycle.

Rs 13/12, 13 switches the Relaiskette (relay chain) to the Prüf-leitung p’;

Over Rs 13/15, 16 all H-Schalter (H-switches) of the Integrierer (integrators) are actuated.

[page 90]

5.1.16. Statisch Prüfen (Static Test)

Pressing the “stat. Prüfen” button actuates Rs 13 which takes over the following tasks:

Rs 13/5, 6 opens, interrupts the Haltekette (hold chain) for Rs 15 and thereby ends every compute cycle.
Rs 13/12, 13 switches the relay chain to the Prüfleitung p’;
Over Rs 13/15, 16 all H-Schalter of the Integrierers (integrators) are actuated.

5.1.17. Betriebsarten-Anzeigelampen (Operating Mode Indicator Lamps)

The lamps for indicating the operating modes “Potentiometereinstellen” (potentiometer setting), “Nullen” (zeroing), “Extern” (external), and “Übersteuerungshalt” (overdrive halt) are switched directly by the respective key switches. All other lamps for operating mode indication signal the state of specific control lines and relays.

Lamp “Pause”: r = h = “1”, neither the “Null” nor the “stat. Prüfen” key pressed.
Lamp “Halt”: r = “0”, h = “1”.
Lamp “Repet. Rechnen”: h = “0”, none of relays 7, 8, 9, or 13 actuated.
Lamps “stat. Prüfen”, “Dauerrechnen”, “mit Halt”, and “Weiter-1×”: h = “0”, respective relay actuated.

[page 91: figure only — Fig. 60, Measuring Device (Meßeinrichtung) schematic. The circuit shows the measurement arrangement of the RA 742 analog computer. Key labeled sections include: upper slide-in unit (oberer Einschub) with operational amplifiers and input sockets (VA-Buchse); lower slide-in unit (unterer Einschub) with the potentiometer measurement lead (Pot.-Meßleitung) and socket 1 (Buchse 1); Nullifier (Nullreifer) stage with 25 k and 100 k resistors; compensation potentiometer (Kompensationspotentiometer) section; socket 3 (Stecker 3) with ±5 V and −10 V reference connections; DVM (digital voltmeter) connection; relay (Relais) output; Ch.E connection; −25 V supply rail; and amplifier supply voltages of ±15 V and ±10 V. The schematic reference number is ARZ 60.]

5.3.18 Measuring Device (continued)

5.3.18 a) Nullification

The preamplifier stage is connected in place of the measuring amplifier. The null point is at ±5 V at the input to the measuring circuit, with an offset voltage of ±0.7 mV referred to the input. The contact resistance is at most ±5 Ω. The instrument Ru 32 provides the reading. An abbreviation switch is provided at the lower slide-in unit. The circuit is supplied via connector 3 to the measuring device through the plug connection. The measuring current is directed through the measurement lead (Meßleitung) to the instrument R 32.

The function designator “Jump-Measuring” (Sprung-Messen) provides for rapid measuring with an appropriate measuring relay function. The positions “Ib” (at the null point), ±5 V, +7.5 V, −9.7 V, and +11.8 V correspond to the Potentiometer “Null-Abgleich”, “DIVM”, “Komp.-Abgleich” and the Potentiometer readout. At the lower slide-in connector Buchse 1, the measurement functions are connected in the half-bridge arrangement.

5.3.18 b) Compensation Potentiometer

The compensation potentiometer, depicted in the Potentiometer readout section, sets the reference voltage value as determined by the potentiometer position. Variations up to ±0.5 V around the nominal value are accommodated. So that any measurement point can be measured without reconnection, the “B” position is used. The potentiometer measurement lead runs from the lower slide-in unit to all computation amplifiers.

5.3.18 c) Nominal Voltage Measurement

The instrument Ru 32 is calibrated and reads the measured voltage directly. The measurement range is −9.8 V and also ±0.5 V at full scale. The full-scale deflection voltage of 11.75 V corresponds to a potentiometer position making any arbitrary voltage measurable. So that no additional measurement is required, every position is included in the measurement range of the instrument.

5.3.19 Timer (Zeitgeber)

The RA 742 analog computer operates at mains voltages of 110 V, 220 V, and 240 V. Upon connection of the mains supply, a stabilized voltage of −12 V is produced at the output of the mains unit, providing a stabilized supply voltage of −12 V for the computer. The measuring device also relies on this supply. A voltage of ±5 V from the reference supply is used for the Chopper supply and the control circuit.

[page 93: figure only — Fig. 61, Timer (Zeitgeber) schematic. The figure shows the schematic of the timer unit. The diagram is divided into labeled sections for upper slide-in unit (Oberer Einschub) and lower slide-in unit (Unterer Einschub). The upper section contains two operational amplifier stages with transistors and resistors (100 kΩ, 100 kΩ, 300 kΩ values visible) feeding into comparator/trigger blocks. Outputs are labeled v_Rechn (compute), v_Rechn (compute), and v_Rechn. The lower section contains the timing control logic with transistors, diodes, relay coil (Rel. E), switches (S 1–S 3), socket (Buchse Ku E), and a reference table. The table shows timing operating modes with rows for various states and columns for conditions. The −25 V supply rail is shown at upper right. Reference number on the schematic is 61 eff.]

[page 94: figure only — Plan 1.1, Desk frame, complete (Tischgestell, vollst.), drawing number 55.3048.750-00 ASP. The rear view (Rückansicht) shows the connector and cable layout of the RA 742 desk frame. The diagram identifies: upper slide-in unit (Oberer Einschub) containing the power supply unit (Netzgerät) on the left and computing amplifiers (Rechenverstärker) on the right, with connectors St 8 and St 8, and sockets Bu 14, Bu 13, Bu 11; interconnection cables (Verbindungskabel) 55.3048.783-00 and 55.3048.782-00 leading to the potentiometer field (Potentiometerfeld) with socket Bu F (dashed border indicating optional/separate unit); function generator (Funktionsgeber) section with sockets Bu 24 and Bu 21; the lower slide-in unit (Unterer Einschub) with connectors St 10, St 9, St 8, St 7, St 6, St 5 and sockets Bu 34, Bu 33, Bu 31.]

[page 95: figure only — Plan 1.2, Desk frame chassis (Tischgestell Chass.), drawing number 55.3048.750-00 ASP. The page shows a detailed wiring or connector assignment diagram for the desk frame chassis in two columns of ten rows each (rows labeled 1 through 0 from bottom to top). Each row shows labeled connector blocks with associated socket/plug designations at right margin (Bu P 1 through Bu P 15 approximately). The diagram illustrates the physical layout and interconnection of the chassis wiring for the upper and lower slide-in unit connectors.]

[page 96: figure only — Plan 1.3, Desk frame chassis (Tischgestell Chass.), drawing number 55.3048.750-00 ASP. Continuation of the connector/wiring layout diagram for the desk frame chassis. Two columns of ten rows (rows 0 through 9 from bottom to top) showing connector block assignments. The right margin labels identify connectors from approximately Bu 20/1 through Bu 40/7. These represent the patch-panel or inter-unit connection points of the analog computer frame.]

[page 97: figure only — Plan 1.4, Desk frame chassis (Tischgestell Chass.), drawing number 55.3048.750-00 ASP. Further continuation of the connector/wiring layout diagram. Two columns of ten rows showing connector block assignments. Right margin labels indicate connector designations continuing the sequence, including references to Bu 20-1 through Bu 3-1 and associated sub-connectors. These wiring plans together document the complete internal cable routing of the RA 742 desk frame.]

[page 98: figure only — Plan 1.5, Desk frame (Bu21), drawing number 55.3048.750-00 ASP. The page shows the pin/contact assignment table for socket Bu 21 in the desk frame. The layout is a grid with columns a, b, c and rows 0 through 9. Labeled entries include: Bu 21 c1 (row 1, column c); rows 2 and 3 labeled Bu #c3 and Bu #c4 with entries for Wert (value) 1/2 and Wert C/2; rows 4–6 labeled Bu #c5, Bu #b5, Bu #b5, Bu #c6, Bu #b6, Bu #b6 with entries for Wert 1/2 and Wert at various columns; row 7 labeled Bu #b7 with Wert entries; row 8 labeled Bu #b8 with Nullpunkt (null point) entries; row 9 labeled Bu #b9 with Nullpunkt entries; row 0 labeled Bu #b0 with Nullpunkt entries. This documents the contact allocation of connector Bu 21 (the function generator socket in the upper part of the frame).]

[page 99: figure only — Plan 1.6, Desk frame (Bu21), drawing number 55.3048.750-00 ASP. Continuation of the contact assignment for socket Bu 21. Grid with columns a, b, c and rows 0 through 9. Labeled rows include Bu #a5 through Bu #a1 and various sub-designations. Several rows contain handwritten-style notation for Wert (value) entries with fractions at various columns. This completes the contact map for socket Bu 21 used for function generator connections.]

[page 100: figure only — Plan 1.7, Desk frame (Bu31), drawing number 55.3048.750-00 ASP. Contact assignment table for socket Bu 31 in the lower slide-in unit. Grid with columns a, b, c and rows 0 through 9. Labeled entries include: Bu 21 c1 / Bu #b1 / Bu #b1 in row 1 with entries Q2, OH, R5 (values at columns a and c); Bu #b2 in row 2 with ”# Para c” entry; Bu #b3 / Bu #a3 in row 3 with “Nullkg M” and “Schirm Ker a/5” entries; rows 4–6 empty or unlabeled; Bu #c7 / Bu #a7 in row 7 with Wert entries; Bu #a8 / Bu #b8 in row 8 with Wert and Nullpunkt entries; Bu #c3 / Bu #a3 in row 9 with Wert entries; Bu #c0 / Bu #a5 in row 0 with similar entries. This documents connector Bu 31 (lower slide-in socket, compute side).]

[page 101: figure only — Plan 1.8, Desk frame (Bu31), drawing number 55.3048.750-00 ASP. Continuation of the contact assignment for socket Bu 31. Grid with columns a, b, c and rows 0 through 9. Multiple row labels with Bu #a-x through Bu #a-y designations. Several rows show Wert (value) entries at various columns. Combined with Plan 1.7, this completes the pin map for connector Bu 31 serving the lower slide-in compute unit.]

[page 102: figure only — Plan 1.9, Desk frame (Bu41), drawing number 55.3048.750-00 ASP. Contact assignment table for socket Bu 41. Grid with columns a, b, c and rows 0 through 9. Multiple labeled rows with sub-designations for Bu #b-x through Bu #a-y entries. Wert (value) and Nullpunkt entries appear at various grid positions. This plan documents the contact allocation for the Bu 41 socket in the desk frame wiring system.]

[page 103: figure only — Plan 1.10, Interconnection cable (Verbindungskabel), Amplifier Inputs (Verstärker-Eingänge), drawing number 55.3048.783-00 ASP. The page shows the pin assignment matrix for the amplifier input interconnection cable. The grid has columns a, b, c and rows 0 through 9. Labeled entries:

Row 0: columns a=09, c=01
Row 9: columns a=10, c=02
Row 8: columns a=*11, c=03
Row 7: columns a=12, center annotated “Schirm 10r / a s… Q, E 3…”, c=04; left side labeled “Eingang Verstärker” (amplifier input), right side labeled “Eingang Verstärker” (amplifier input)
Row 6: columns a=13, c=05
Row 5: columns a=14, c=06
Row 4: columns a=15, c=07
Row 3: (blank), c=08
Row 2: (blank)
Row 1: center=Gehäusemasse (chassis ground) This cable (part number 55.3048.783-00) carries the input signals from the patch panel to the computing amplifiers.]

[page 104: figure only — Plan 1.11, Interconnection cable (Verbindungskabel), Amplifier Outputs (Verstärker-Ausgänge), drawing number 55.3048.782-00 ASP. The page shows the pin assignment matrix for the amplifier output interconnection cable. The grid has columns a, b, c and rows 0 through 9. Labeled entries:

Row 0: columns a=09, c=01
Row 9: columns a=10, c=02
Row 8: columns a=*11, c=03
Row 7: columns a=12, c=04; left side labeled “Ausgang Verstärker” (amplifier output), right side labeled “Ausgang Verstärker” (amplifier output)
Row 6: columns a=13, c=05
Row 5: columns a=14, c=06
Row 4: columns a=15, c=07
Row 3: (blank), c=08
Row 2: left=Anwahl Verst. 17, right=Anwahl Verst. 18
Row 1: left=Anwahl Verst. 16, center=Gehäusemasse (chassis ground), right=Anwahl Verst. 19 This cable (part number 55.3048.782-00) carries the output signals from the computing amplifiers back to the patch panel.]

[page 105: figure only — Plan 1.12, Lower Slide-In Unit (Unterer Einschub), connectors St. 5 and St. 10, Parallel Connection (Parallelschaltung), drawing number 55.3048.400-00 ASP. The page shows the contact assignment matrix for connectors St 5 and St 10 (used in the parallel connection of the lower slide-in unit). The grid has columns a, b, c and rows 0 through 9. Entries:

Row 0: a=h_ext, b=+10 V Ref. ext., c=Geh.E (chassis ground)
Row 9: a=Par.schltg. Halt (parallel switching, halt), b=1× Rechnen (1× compute), c=+10 V Ref.
Row 8: a=Null, b=Rechnen mit Halt (compute with halt), c=−10 V Ref.; note: asterisk (*)
Row 7: a=stat. Prüfen (static test), b=r, c=r_ext
Row 6: a=Q6, b=h, c=m_NN
Row 5: a=Q5, b=ÜH (overvoltage monitoring?), c=−25 V
Row 4: a=Q4, b=Par.schaltg. Pause (parallel switching, pause), c=Ch.E; footnote: ¹) bei St 10 Q1’ bis Q6’ (at St 10, Q1′ through Q6′)
Row 3: a=Q3, b=Dauer (continuous), c=VE
Row 2: a=Q2, b=Pause, c=Rel.E (relay enable)
Row 1: a=Q1, b=Pol. (polarity), c=Ü2 This table specifies the signal allocation at the lower slide-in parallel-connection interface.]

[page 106: figure only — Plan 1.13, Lower Slide-In Unit (Unterer Einschub), connector St. 8, to Function Generator (zum Funktionsgeber), drawing number 55.3048.400-00 ASP. The page shows the contact assignment matrix for connector St 8 at the lower slide-in unit (interface to the function generator). The grid has columns a, b, c and rows 0 through 9. Entries:

Row 0: a=Eing. U11 (input U11), b=Schirm für a, c 0 (screen/shield for a, c 0), c=Eing. U21 (input U21)
Row 9: a=Eing. U12 (input U12), b=Schirm für a, c 9 (shield for a, c 9), c=Eing. U22 (input U22); with sub-labels F1 (left) and F2 (right)
Row 8: a=+x, b=Ausg. U11 (output U11), c=+x
Row 7: a=−x, b=Ausg. U12 (output U12), c=−x; sub-label F1 on b
Row 6: a=+y, b=Ausg. U21 (output U21), c=+y
Row 5: a=−y, b=Ausg. U22 (output U22), c=−y; sub-labels NW1 (left) and NW2 (right), F2 on b
Row 4: a=G1, b=Schirm für a, c 4 (shield for a, c 4), c=G1
Row 3: a=Gx, b=Schirm für a, c 3 (shield for a, c 3), c=Gx
Row 2: a=G2, b=Schirm für a, c 2 (shield for a, c 2), c=G2
Row 1: a=Gy, b=Schirm für a, c 1 (shield for a, c 1), c=Gy This table defines the signal allocation at the function generator interface connector.]

[page 107: figure only — Plan 1.14, Lower Slide-In Unit (Unterer Einschub), connector St. 9, to DEX 100, drawing number 55.3048.400-00 ASP. The page shows the contact assignment matrix for connector St 9 at the lower slide-in unit (interface to the DEX 100 external device). The grid has columns a, b, c and rows 0 through 9. Entries:

Row 0: a=H15, b=R15, c=Pa
Row 9: a=H11, b=R11, c=Ha
Row 8: a=H06 (with asterisk *), b=R06, c=Re
Row 7: a=H02, b=R02, c=Il
Row 6: a=Q6′, b=h, c=Komp.sch. 22 (compensation switch 22)
Row 5: a=Q5′, b=r, c=Komp.sch. 21 (compensation switch 21)
Row 4: a=Q4′, b=pr, c=Komp. 2
Row 3: a=Q3′, b=p, c=Komp.sch. 12 (compensation switch 12)
Row 2: a=Q2′, b=Geh.E (chassis ground), c=Komp.sch. 11 (compensation switch 11)
Row 1: a=Q1′, b=Rel.E (relay enable), c=Komp. 1 This table defines the signal allocation for the interface to the DEX 100 external computing device.]

[page 108: figure only — Plan 1.15, Lower Slide-In Unit (Unterer Einschub), Bu (connector) to Potentiometer Field (zum Pot.feld), drawing number 55.3048.400-00 ASP. The page shows the connector/socket pin assignment for the potentiometer field interface at the lower slide-in unit. The diagram is arranged as a grid of labeled rectangular blocks, each representing a socket or plug contact. Entries identified (in approximate layout order from top-left to bottom-right):

Top row: Eing. Pot 1 (input pot 1), Ausg. Pot 1 (output pot 1), Eing. Pot 2 (input pot 2), Ausg. Pot 2 (output pot 2)
Second row: Eing. Pot 3 (input pot 3), Ausg. Pot 3 (output pot 3), Eing. 1 Pot 5, Eing. 2 Pot 5, Ausg. Pot 5
Third row: Eing. Pot 4 (input pot 4), Ausg. Pot 4 (output pot 4), Eing. Pot 8 (input pot 8), Ausg. Pot 8 (output pot 8, partially cut off)
Fourth row: Eing. Pot 7 (input pot 7), Ausg. Pot 7 (output pot 7), Eing. 1 Pot 10, Eing. 2 Pot 10, Ausg. Pot 10
Fifth row: Eing. Pot 8, Ausg. Pot 8, Eing. Pot 9 (input pot 9), Ausg. Pot 9
Below these: Pot E, m Pot (entries for the potentiometer reference and measurement bus)
Then: Pot E with −10 V; Pot E with −10 V; Pot E with +10 V and −10 V entries
Further entries: Eing. Pot 12 / Ausg. Pot 12, Eing. Pot 13 / Ausg. Pot 13
And additional rows for Pot 11, Pot 16, Pot 17, Pot 18, Pot 19, Pot 20 with corresponding Eing. (input) and Ausg. (output) designations This plan documents the complete pin/socket assignment for the connection between the lower slide-in unit and the potentiometer field of the RA 742 analog computer.]