Analog Computers

Reference / Paper · 1978

Practical Electronics, September 1978 — Analogue Computer Part 1: Mathematical Operations and Circuits

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First installment of a multi-part constructional series on building an analogue computer, published in Practical Electronics (Vol. 14, No. 13, September 1978). Covers the fundamental theory and circuit building blocks: summing amplifiers, integrators using 741 op-amps, coefficient multipliers (potentiometers), and mode-control logic (Compute / Hold / Reset with Initial Conditions). An overload warning facility is also described. Construction details were deferred to Part 2 (October 1978 issue).

Manufacturer
Practical Electronics
Author
P. J. Kronis BSc
Year
1978
Type
Reference / Paper
Language
English
Learning track
general theory
Pages
84
Credit
IPC Magazines Limited, 1978. Article by P. J. Kronis BSc in Practical Electronics Vol. 14, No. 13.
  • Practical Electronics
  • analog computer construction
  • operational amplifiers
  • integrators and summers
  • analog computing theory

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Practical Electronics, September 1978 — Analogue Computer Part 1: Mathematical Operations and Circuits

ts Teleplay prese now to for library to enjoy cartridge assemble all the familyworks White TV you and full colour and all in - OK on Blackyou pounds ir will saverun, of easy A whole games - the long STAROFFERS COLOURCAR FREE WITH of a Professional Football consisting are. of 10 gamesKit a All .holes kit! at consists be snuffed on which enjoyable superbly etc. *MainsAdaptor. that cannotone cartridge this Shoot of a bargain Controls(1 & 2 players), it is to assemble consists Hand easy We offer how OFFER Joystick Basketball to you all this Box Hockey,Y ou'll be surprised Moulded 2 players), Our INTRODUCTORY for ONLY Inject required. (1 & Finished Squash equipment Solo Tennis, No Special P&P. -drilled pre VAT and inc. bled -$ * C28. 90 Fully Assem Add £7.00 a NE VV Hand will and those 3 months to you include Every available become under productionVVipe Out of these already Space War, Fuliv price cartridge Assembled Submarines,More. The £19 depending Add £12 to game. and many £14.90 of the £3.00 include: Controls will vary complexity kit - £12.90 available the and Hand £.18.90 NOVV basic upon with Cartridges - Cartridge Controls already 4 games and Hand Additional Controls Cycle - Stunt Battle - Cartridge Cartridge 2 games 'Tank Race Road he co Controls game - p rinted follow Cartridges to cornapleteeavvyith comeease instructions. ly Electrical knowledge is not a necessity to assemble this project - just simple soldering. Cheques and Postal Orders to be made payable to TELEPLAY: send your order (No Stamp Needed) to Teleplay, Freepost, Barnet, EN5 2BR or telephone your order quoting your Barclaycard or Access number. Queries and Technical Advice offered either by phone or by calling at our shop. BARCLAYCARD SHOP OPEN -10am to 7pm - Monday to Saturday CLOSE TO NEW BARNET BR STATION - MOORGATE LINE Alw wein.w 4ccrm All parts fully guaranteed. IIEUROPE'S LARGEST STOCKIST OF TV GAME COMPONENTS. 14 Station Road, New Barnet, Herts EN5 1QW Tel: 01-440 7033/01-441 2922 PRACTICAL ELECTRONICS VOLUME 14 No. 13 SEPTEMBER 1978 CONSTRUCTIONAL PROJECTS ANALOGUE COMPUTER -1 by P. J. Kronis BSc Mathematical operations and circuits COMBINATION LOCK by E. A. Parr Double combination for added security 970 990 THERMOSTAT CONTROL by M. Edmunds For the photographer who does his own developing SOUND TRACK MONITOR by J. Schmid Alerts the operator when the end of a recording is reached 1002 1006 METRONOME by M. Butt Simple emphasised beat unit KEYBOARD by L. G. Parkin BA Provide an eight bit binary word by pressing two keys 1010 1014 GENERAL FEATURES WAVE ENERGY by M. Abbott Can the sea provide the UK with electricity? 976 STRICTLY INSTRUMENTAL by K. Lenton-Smith Signetics TDA 1008 electronic music i.c. 988 INGENUITY UNLIMITED Simple Clock-Beethoven's Doorbell-Electronic Combination Lock-Distortion Assessment-Protection for a Model Train Speed Controller-Simple Alarm SEMICONDUCTOR UPDATE by R. W. Coles 993 A look at some recently released devices 998 NEWS AND COMMENT EDITORIAL READOUT 969 A selection of readers letters 974 BOOK REVIEWS Selected new books we have received 980, 1013 MARKET PLACE Interesting new products 985 INDUSTRY NOTEBOOK by Nexus What's happening inside industry SPACEWATCH by Frank W. Hyde Soyus-29 and Salyut -6, USSR Launchings, India and the USSR, GOES -3, Place in Space 1001 1005 PATENTS REVIEW Thought provoking ideas on file at the British Patents Office 1020 Our October issue will be on sale Friday, 8 September 1978 (for details of contents see page 975) IPC Magazines Limited 1978. Copyright in all drawings, photographs and articles published in PRACTICAL ELECTRONICS is fully protected, and reproduction or imitations in whole or part are expressly forbidden. All reasonable precautions are taken by PRACTICAL ELECTRONICS to ensure that the advice and data given to readers are reliable. We cannot, however, guarantee it, and we cannot accept legal responsibility for it. Prices quoted are those current as we go to press. Practical Electronics September 1978 953 TWICE the I.C.E. MULTIMETERS in at in HALF the Size The I.C.E. range of multimeters provide an unrivalled combination of maximum performance within minimum dimensions, at a truly low cost. Plus, a complete range of add-on accessories for more ranges, more functions. Supertester 680R (illustrated) Supertester 680G 20ki2/V, ±1% fsd on d.c. * 20k1//V, ±2% fsd on d.c. 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AN ELECTRONIC VERSION OF TWO-UP OR ODDS AND EVENS.- We supply a complete kit of parts which includes a strong case and attractive front panel to give the finished game a long life and professional appearance. Full assembly instructions are supplied. 'If you can solder you can make this great game: An ideal first project to introduce you to electronics. Not only will 'FLIP' start you on a great hobby but you will own a game which will amuse you and your friends for hours. POWER SUPPLY UNIT PP1 - switched 3, 41, 6,171. 9 and 12 volts at 500mA, with on/off switch and pilot light. Size: 130 x 55 x 75mm approx. Our Price: £6.00 + 8% VAT i SIX -PIECE MINIATURE SCREWDRIVER Complete Kit: £5.25 + 8% VAT I SET Post Free! I Personal Tuition and Guaranteed Success BARGAIN LOUDSPEAKER Goodmans 5" 8 ohm long throw heavy duty L/SPKR. The expert and personal guidance by fully qualified tutors, backed by the ICS guarantee of tuition until successful, is the key to our outstanding record in the technical training field. You study at the time and pace tbat suits you best and in your own home. In the words of one of our many successful students: "Since starting my course, my salary has trebled and I am expecting a further increase when my course is completed." Mounting plate is integral with US chassis and has fixing holes with centres spaced at 51 (diagonally) Only £5.00 + 121% VAT. Six precision screwdrivers in a hinged plastic box. Blade sizes: 0.8mm, 1.4mm, 2mm. 2.4mm, 2. 9mm, 3.8mm. Our Price: E1.75 + 8% VAT 1 . . I I I PIEZO ELECTRIC HORN UNITS High Quality. High Power Tweeter. No Xover reqd. Freq. Response: 3.8kHz-28kHz. Spec. 2 WAY 8 OHM HEAVY DUTY XOVER. sheet sent on receipt of S.A.E. A 2 way 8 ohm H/D Xover suitable for US systems up to 100W. Input via screw terminals. 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TWIN BANK12 LIGHT Name f7.99 BC Fitt ing Fitting f7.9g ILr ow length UNIT Address 100 WATT SPOT LAMPS RED YELLOW. GREEN 3 lamas BLUE Age CLEAR E 11 .50 wen i £4 50 8.0 or ES.inIng 11PrWfa (less lamps( £1&50 S Bc Fitting Fi tting £18-50 E 1 To ICS, Dept. 273Y , Intertext House, London SW8 4UJ or telephone 01-622 991 1 (all hours) mid IMel not v V& r and POST II PACKING DM Seed 2, for illustrated leaflet & nee his A L BE N ENGINEERING Co LTD., DEPT. PE THE CRESCENT, WORSTHORNE, BURNLEY LANCS. Tel. Burnley 20940 956 Practical Electronics September 1978 TTL 74* WATFORD ELECTRONICS 7401 7402 7403 7404 7405 35 CARDIFF RPOAD, WATFORD, HERTS., ENGLAND MAIL ORDER, CALLERS WELCOME. Tel. Watford 40588/9 ALL DEVICES BRAND NEW, FULL SPEC. AND FULLY GUARANTEED. ORDERS DESPATCHED BY RETURN OF POST. TERMS OF BUSINESS: CASH/CHEQUE/ P.O.s OR BANKERS DRAFT WITH ORDER. GOVERNMENT AND EDUCATIONAL INSTITUTIONS' OFFICIAL ORDERS ACCEPTED. TRADE AND EXPORT INQUIRY WELCOME. P&p ADD 30p. TO ALL ORDERS UNDER £10.00. OVERSEAS ORDERS POSTAGE AT COST. AIR/SURFACE. MINIMUM ORDER £2.00 PLEASE. VATE sport orders no VAT Applicable to U.K Customers only Unless stated otherwise, all prices are exclusive of VAT. Please add 8% to demcm marked A. To the rest add 125% We stock many more items. It pays to visit us. We are situated behind Watford Football Ground. Nearest Underground/BR Station: Watford High Street. Open Monday to Saturday 9.00 am - 6.00 pm. Ample Free Car Parking space available. POLYESTER CAPACITORS: Axial lead type. (Values are in pF) 400V: 0.001. 0.0015. 0.0022, 0.0033 Sp; 0.0047, 0.0068. 0.01. 0.015. 0.018 9p; 0.022. 0.033. 10p; 0.047. 0.068 14p; 0.10150; 0.15, 0.22 22p; 0.33. 0.47 39p; 0.68 45p. 160V: 0039. 0.15. 0.22 13p; 0.33. 047 22p; 0.68, 1.0 29p; 1.5 33.p; 2.2 38p; 4.7 47p. DUBILIER: 1000V: 0.01.0.01516p; 0022 18p; 0.047 16p; 0.1 34p; 0,47 43p. POLYESTER RADIAL LEAD (Values in F1 250V: 0-01, 0-015; 0-022, 0-027 Sp; 0-033, 0-047. 0-068, 0-1 7p; 0-15 12p; 0-22, 0-3314p; 0.47 16p; 0-68 20p; 1-0 24p; 1-5 27p; 2-2 31p. FEED THROUGH CAPACITORS 1006F 350V Bp 7406 7407 7408 7409 7410 7412 7413 7414 7416 7417 7420 50V: 10 7p; 50. 100. 220 25p; 470 50p; 1000. 2200 68p; 40V: 22. 33 9p; 10t) 12p; 3300 62p; 4700 64p; 35V: 10, 33 7p; 330. 470 32; 1000 49p; Sp; 25V:10.22, 47847 p; 80. 100. 160 8p; 220. 250 13p; 470. 640 26p; 1000 27o 1500 30o:2200 P: 3300 5700 54p; 16V: 10, 40, 47, 68 7p; 100, 125 Sp; 330, 470 16p; 1000, 1500 20p; 2200 34p;10V: 4. 1-00 6p; 640 10p; 100014p. TAG -END TYPE: 70V: 2000 96p; 4700 121p; 50V: 3000 75p; 40V: 4000 70p; 2500 65p; 100 50 100 190p. 25V: 4700 443p; 2000 37p; 40V: 2000 2000 95p; 325V: 200 TANTALUM EAD C4PACITORS 022 033.0.47.068 OPTO POTENTIOMETERSIA8 or EGENI '0 2 20F 33 47 6 8 25V: 5 10 20V: 1.5 18V: 10pF 13p each Carbon Track 5W Log & 5W Lower values 5000. 1K & 2K din only/. Single 27p 580-2M0 single gang 27p alp 580-2M0 single gang D/P switch 47. 68. 100.3V: 68. 100pF. 20p each 580.2M0 dual gang stereo 35V: 0 1 uF I 47.100 40p. 10V: 229F. 33, 47 6V: MYLAR FILM CAPACITORS 70p SLIDER POTENTIO 100V: 0 001 0 002 0005.0 Olyf Sp 7p 0 015 0 02 0 04 0 05 0 056*F lip 0 15 0 2 9p SOV: 0 47.. o 0-25W log and 1106.1f values 60rnrn CERAMIC CAPACITORS: SOY Sell Sock Graduated Betels 0 5pF to lOnF 3p each 4p each 6p I5nF 22nF 33nF 47nF 01 POLYSTYRENE CAPACITORS 100F m 1nF Sp: SILVER MICA Waives m pF) 3-3. 4-7. 6 8 10 12 18 22. 33 47. 50. 68. 75. Sp each 82. 85. 100. 120. 150.220 250 300.330 360.390.600.820111p each RESISTORS - 22p 5 25086 5-45pF 60pF 88pF 3011 ION TRIMMERS COM 3 40pF 10 - 80pF 25 -190p1 VAL 100 E12 E12 1 99 1.5p 2p 5p 7% Metal Film 100- IMO OP 2.20- Km (24 TIL307 299 675 68 ORP12 TIL313 C Cth 3"105 TIL321 C An 5'115 TI L322 C Cth 5'115 DI704 C Cth .3" 99 DL707 C.A. .3" 99 FND357 140 LCD 31 digit 976 975 LCD 4 digit flp 1.5p 4P 4P 1% Metal Film 50-1M Op lop too mice applies to Resistors of each type not mixed values PE String ENSEMBLE 25p 38p 100 500pF 1250pF noise PANG( 5W 2-20-4 7M ON 2-20-4 7M 20p MINIATURE TYPE TRIMMERS 25 6pF 3-10pF 10-40pf Low High 2 54 7 Seg Displays TIL312 C An 3" 105 make 5% Carbon Stability Miniature TOp each 7pF 4 150F 6 -25pF 13.30pF Ens Spare Cl 2N5777 8p 10p 10p 0-25W 2000-4-7140 Van CERAMIC TRIMMER CAPACITORS 2 20* 0-25W 1001-3 3M0 Hofil 1 5nF to 47nF 10p. 1000 1800.2000.2200 80p PRESET POTENTIOMETERS Vertical & Flordontal CLIW 500- -5810 Miniature LEDs plus clip TIL209 Red 13 TIL211 Grn 18 TIL212 Yellow 22 2" Red 17 2" Yellow Green21 LS400ips 70p 580.5001(0 single gang 1080.50080 dual gang ELECTRONICS* Components now available. SWITCHES* TOGGLE 2A 250V 28p SPST 38p DPDT 54p 4 pole on/off SUB -MIN TOGGLE SP changeover SPST on/off DPDT 8 tags 59p 54p 70p DPDT Centre off 79p DPDT Biased 115p SLIDE 250V: 2.5mm 3.5mm Plastic body Screened chrome 120 STEREO DIN moulded with break contacts open metal 13p 184 p 23p 31p MONO PLUGS SOCKETS In Line 13p 817 20p 14p 14p Sp single 11p Se Op datable PIN Loudspeaker CO -AXIAL VIVI P80110assorted colours Metal Screamed 12p 10,3 -wary 2mm 10p 10p 12p 10p Illp WANDER 3mm 41. Sp 9p Ornrn ITT 14p 1A DPc./ v r 15 IA DPDT 13p 4 pole c/ogTo N24p BUTTON in line couplers lip 20p 240 184 15p 15p 18p 3 4 5 Pin Audio 1A DPDT SOCKETS JACK PLUGS ligl SPDT lover 18p 22p n/o ff DPDT 6 Tag 600 650 85p SWITCHES * Miniature Non -Locking Push to Make 15p Push to Break 25p ROCKER (white) 10A 250V SP changeover centre off 30p 23p ROCKER: (black) on/off 10A 250V ROCKER: Illuminated (white) Lights when on: 3A 240V 52p ROTARY: (ADJUSTABLE STOP/ 1 pole/2-12 41p 45p ;1)%2 121/ ?SUVA% 4A0C43Airnp DIL SOCKETS * I Low Profile -Texas) 12p; 16 2483,431111X ; 1244 128 pin 20p; 21g pin 55p. DIGITAL MULTIMETER Announcing DM900 - The Digital Multimeter with a difference - It measures Capacitance too. las published in E.T.I. August 1978) Throw away your analogue meters, here's digital accuracy at only half the price of an equivalent commercial Multimeter. VDU CHIP and MODULE The DM900 is a 31 digit multimeter with an Convert your TV into a VDU by using the new Thomson-CSF, 0.5in LCD. display incorporating: TV -CRT controller chip SF.F 5 AC & DC Voltige ranges; 6 Resistance ranges. 96364. 16 lines by 64 characters, text refreshment, cursor manageThe prototype accuracy is better than 1%. This is a unique design using the latest MOS ICs ment on TV screen, line erasing, and due to the minimal current drain, is powered line end erasing. Compatible with by only one PP3 battery. There is also a battery any computing system. (Send 20p check facility. plus SAE for full technical data.) £11.50. DM900 is an attractive hand-held lightweight SFF 96364E f4.50* device, built into a high impact case with carrying AY -5-1013 UART handle and has been ingeniously designed to 71301 ROM £8.20* simplify assembly. £2.05* SFS80102 RAM 1K Never before have all these features been offered 74L8163 RAM £0.95e to the electronics enthusiast in a single unit. E1 36.50° Complete module 5 AC & DC Current ranges; 4 Capacitance ranges. SPECIAL INTRODUCTORY OFFER Price: £49.95* only Ip&p insured add 75p) Ready Built units available on order Send SAE for leaflet. (Demonstration on at our shop) Practical Electronics September 1978 ASC1 1 Keyboards' Full 56 Key ASCII coded keyboards now available £49.508 (P & P 75p1 51 30 30 16 29 7421 7422 7423 7425 24 27 27 36 27 35 17 25 40 30 33 7426 7427 7428 7430 7441 ELECTROLYTIC CAPACITORS: Axial lead type (Values are in pF) 47. 32. 50 12p; 63, 100 27p; 15, 22 63V 0 47. 1 0, 1.5. 2.2. 2.5. 3.3. 4.7, 6.8, 17 17 15 20 17 30 7411 7432 7433 7437 7438 7440 7442 7443 7444 7445 7446 7447 7448 7450 7451 7453 7454 7460 7470 7472 7473 7474 7475 7476 7480 7481 7482 7483 7484 7485 7486 7489 7490 7491 7492 7493 7494 13 13 14 14 14 18 38 38 7400 17 74 68 115 112 94 94 82 56 17 17 17 17 17 28 25 32 27 38 36 48 86 69 72 95 106 31 210 33 76 3238 78 7495 85 7496 57 7497 188 74100 119 74105 62 74107 29 74109 64 74110 74111 74112 64 68 88 74116 188 74118 83 74119 119 74120 116 74121 25 74122 46 74123 48 74125 38 74126 57 74128 74 74132 73 74136 73 74141 68 74142 269 74143 314 74144 314 74145 86 74147 175 74148 109 74150 99 74151 64 74153 64 74154 96 74155 53 74156 80 74157 87 74159 210 74160 82 74161 92 74162 92 74163 92 74164 105 74165 105 74166 181 74167 20 74170 230 74172 626 74173 170 74174 87 74175 87 74176 75 74177 78 74178 102 74180 86 74181 165 74182 160 74184 136 74185 136 74188 275 74190 116 74191 105 74192 105 74193 105 TRANS S TORS AC117* AC125* AC126* AC127* AC128* AC141* 35 BC170 19 BC171 19 BC172 BC177* BC178* 24 BC179* 18 18 AC141K* 38 BC182 AC142* 24 AC142 K* 38 AC176* 18 AC187* 20 AC188* 20 ACY17 ACY18* ACY19* ACY20* ACY21 ACY22* ACY28* ACY39 ACY40* ACY44 AD 140* 4056 134 74195 74196 74197 95 99 85 4059 4060 480 75491 75492 75 80 4062 4063 4066 4067 4068 999 110 4071 21 21 21 741C* 8 pin 23 85 753 74198 150 75150 110 CMOS* BC308 BC328 8C338 BC119* BC134 BC135 BC136 BC137 BC140* BC142* BC143* BC147 BC148 BC149 BC153 BC154 BC157 BC158 BC159 BC160 BC167A BC168C BC169C 17 19 19 19 15 19 26 60136* 90137* 60138* 130139* BD 140* BD142* 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 7 7 17 11 10 15 14 14 9 21 28 11 9 10 14 13 13 12 30 30 37 36 36 36 36 59 80145* 198 BD696A* 75 BDY17* 195 BDY60* 110 8DY61* 165 BF115* BF154* 8E156* 8 14 14 10 13E17 6F1763* 11 11 13E179* 8F177* 6E178* 5F180* 8F181* 8E182* 12 8E183* F184* 10 27 11 18 18 42 86 89 45 89 89 48 99 91 88 20 66 19 180 45 81 99 50 205 100 145 196 111 325 100 108 320 105 80 75 94 88 145 128 87 58 48 48 72 72 4052 72 4053 4054 110 4055 128 8E194 80222* 80 20 BD695A* 75 18 87 50 50 4031 19 20 28 25 25 18 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 AD149* BC441* AD161* BC461* AD162* 11 BC547 AF114* 8C548 11 AF115* AF116* BC549 11 BC557 13 AF117* BC558 12 AF118* BCY30* 57 AF121* BCY34* 75 AF124* BCY39* 40 AF125* BCY40* 78 AF127* BCY43 75 AF139* BCY58* 22 AF178* 22 BCY59* AF180* BCY70* 15 AF186* BCY71* 15 AF239* BCY72* 16 ASY26* BCY78* 20 ASY27* 82 BC107* 9 BDI15* BC107B* 10 BD121* 95 98 BC108* 9 BD123* 80124* 115 BC1088* 12 BC108C* 12 130131* 38 BC109* 9 80132* 38 BC109B* 12 BD133* 43 BC109C* 12 80135* 36 BC113 BC114 BC115 BC116 BC117 BC118 105 4011 9 10 9 48 39 69 90 42 42 25 25 25 25 55 48 55 35 35 36 70 70 60 42 40 45 17 4002 4006 4007 4008 4009 4010 BC212 BC212L BC213 BC213L BC214 78 BC214L BC30713 17 4001 10 9 10 9 10 BC187* 15 4000 BC182L BC183 BC183L BC184 BC184L 35 BC186 40 40 40 35 40 40 206 266 299 126 382 4513 4514 4515 4516 4517 74194 105 22 25 29 25 25 BF195 BF196 BF197 BF198 BF200* BF224A 8E244 BF256* BF257* BF258* BF259* BF394 BF594 BF595 BFR39 BER40 8FR79 BFR80 BFX29* 4057 2570 13FX88* EiFY18* BP/50* BFY51* BFY52* 13FY71* BSX20* BSX2O* BSY65* BSY95* 4072 4073 4075 4076 4077 4078 4081 4082 4085 4086 4089 4093 4094 4095 4096 4097 4098 4099 4160 4161 4162 4163 4174 4175 4194 4408 4409 4410 702 709C 14 Din 22 40 21 20 21 74 73 150 86 190 105 106 372 110 145 109 109 109 109 110 99 108 720 720 720 995 747C* 748C* 81 8030 8CC* AY -1-0212 AY -1-1313 AY -1-5051 AY -1-6721/6 70 MC1710CG 36 MC3401 150 MC3340P* 159 MC3360P 370 MFC400013 580 MFC6040* 680 MK50398* 145 195 385 978 MK50362* 223 190 746566* CA3035 CA3043 CA3046 CA3048 CA3075 71 200 NE567* NE571* 825 4451 295 LM380 4415F 795 4415V 795 4433 1225 CA3080E* CA3081 CA3089E CA3090AQ CA3123E 4440 1275 LM348* 4450 295 LM379* 4490F 696 LM381 4490V 525 LM381AN 4501 4502 4503 4506 4507 4508 4510 17 120 69 LM382 LM1458* LM3900* 51 LM3909N* 55 LM3911* 298 M252AA* 99 M253AA* 120 375 95 145 241 125 50 60 70 125 750 795 88 4511 150 MC1303 260 4512 98 MC1304P 32 ZTX314 10 0C42* 55 ZTX326 10 0C43* 10 10 18 0C44* 0C45* 25 25 28 28 26 24 24 28 23 24 50 20 20 20 20 18 18 36 45 45 47 45 45 47 18 22 TIP31C* E5567 85 TIP3113* TIP32* TIP32A* TIP32B* MD8001*158 TIP32C* ME4102 10 TIP33* ME6002 14 TIP33A* MJE2955* 11 MJE3055* 80 TIP34B* 110 TIP34C* 110 TIP35* 219 TIP35A* 225 TIP35C* 270 TIP36A* 265 TIP36C* 325 30 38 36 36 50 50 MPSA55 MPSA56 MPSA70 24 24 34 TIS43 TIS44 TIS46 TIS50 TIS60 TIS62 MPSUO6 54 T1S74 MPSUO2* 58 MPSUO5 48 160 80 99 48 29526* 29696* 2N697* 29698* 2N699* 13 14 19 15 25 25 25 58 35 21 39 39 2N706A* 19 29707 50 2N708* 19 29914* 32 2N918* 27 2N918* 30 29920* 61 29930* 18 29961* 61 2N1131* 22 2N1132* 22 291302* 35 291303* 50 291304* 50 291305* 28 291306* 36 2N1307* 50 291308* 443 291613* 23 TIP2955* 63 TIP3055* 52 TIS90 TIS91 ZTX107 ZTX108 11 11 11 ZTX300 13 16 18 21 ITX109 ZTX301 ZTX302 ZTX303 ZTR304 ZTX311 90 293702 2N3703 2N3704 2N3705 2N3706 10 11 10 11 2N3707 2N3708 2N3709 10 10 10 10 2N3711 10 2N3819 2N3820 22 32 293903 293904 2N3905 2N3906 18 18 18 17 294058 294061 17 17 294289 20 65 42 42 20 293710 16 293715* 250 2N3772* 170 293773* 288 2N3823* 65 2N3824* 70 293866* 90 2N4037* 52 294064* 120 294236* 145 2N4859 2N5135 2N5136 2N5138 2N1671* 190 291671B*195 2145179* 60 291893* 28 2145180* 50 2N1986* 60 295191* 65 2742160* 105 295305* 24 292217* 48 295457 32 2N2218A*31 292219A*22 2N2220A*26 TIP33B* 100 292221* 23 TIP33C* 105 292222* 20 TIP34* 85 292297 46 MPF102 MPF103 MPF104 MPF105 MPF106 MPF107 MPSA05* 24 MPSA06* 24 ZTX550 215 115 228 155 353 300 70 220 330 595 320 TDA2020 52 TL081CP* 96 TL082CP* 130 TL084CP* 198 UAA170 105 ZN414 130 ZN424 24 293614* 169 40 293615* 135 24 20 2N3663 63 73 64 82 130 MJ491* 160 MJ2955*120 MJE340* 45 MJE370* 55 MJE371* 60 MJE520* 45 MJE521* 65 TDA1022* TIP41A* TIP418* TIP42A* TIP42B* TIP29 TIP29A TIP29C TIP30 TIP30A TIP308 TIP30C ZTX531 211 105 70 260 292303* 46 2N2368* 21 2N2369* 15 292476* 125 292483* 28 2N2484* 30 2N2646* 48 2N2784* 55 292846* 140 292894* 30 0C141* 0C170* 0C171* 0C201* 0C202* 0C203* 0C204* ZTX504 140 140 180 85 OC140* ZTX501 ZTX502 ZTX503 211 TBA800 TBA8105 TBA820 TBA9200 TIP34A* 0C122* 0C123* 0C139* BU105 90 ZTX341 120 700 295 TBA651 ZTX500 TIP31* TIP31A* BU205* 190 BU208* 225 31 157 TBA641BX11 250 20 28 19 25 30 36 76 76 28 45 48 44 48 48 85 85 85 40 40 75 85 85 85 43 44 60 47 47 84 65 40 40 40 66 45 49 70 70 80 80 ,0046* 28 0070* 18 0071* 24 0072* 50 0076* 26 0077* 26 0079* 30 0081* 22 0082* 40 0083* 38 0084* 18C 450 RAM2102-2* 210 4435 4412E1380 635 650 MM2102-2* 190 280 545 4412F 1650 195 50 92 99 99 395 79 69 150 89 85 97 MM2112-29* 310 AY -3-8500* 210 NE518A* AY -3-8710* 29 AY -5-1224A* 260 NE555* 60 AY -5-1230* 450 NE556DB* 325 CA3011* 82 NE560* 410 170 NE561* CA3020 410 170 NE562* CA3023 185 80 NE565A* CA3028A* 30 25 0C29* 0C35* 0C36* 0C41* 175 MI 108 268 199 4419 4422 4411 BSY95A* 25 MJ400* MC1310 76 MC1312P0 35 MC1458* 48 MC1496 45 MC1488* 125 MC1489* 22 MC1495* 4522 102 175 RC4136D* 80 ROM2513* 190 SG3402 210 SN76003N 390 SN76013N 200 SN76023N 85 SN76033N CA3130* 92 SN76115N CA3140* ICL7106Ev* 975 SN76227 CM7205* 1150 TAA621AX I 170 TAA661A LM3001H 30 TAA700 LM301A 110 TAA960 LM308 195 TBA120S LM318 79 TBA5400 LM324* 80 TBA5500 LM339* MPSU52* 65 MPSU55* 53 MPSU56* 56 24 MPU131* 39 25 0C25* 120 30 0C26* 150 20 0C28* 99 30 30 30 30 58 380 199 152 99 165 85 4521 LINEAR IC'S 710* 40698E 20 723* 32 733* 4070 BFX81* 130 BFX84* BFX85* BFX86* BFX87* 99 4061 2380 4526 4527 4528 4529 4530 4518 4519 4520 295458 2N5459 2N5485 32 32 32 2N5777* 54 296027 40311* 40 50 40313* 126 85 40316* 52 40317* 85 40324* 52 40326* 62 40327* 40347* 80 40348* 101 40360* 43 40361* 45 2N2904A*22 40362* 48 292905A*20 40407* 50 2N2906* 18 40411* 289 292907* 20 40412* 63 95 2N2907A*22 40467* 292926G 10 40576* 190 80 40594* 90 292926R 8 40595* 65 292926Y 8 40603* 2N3011* 24 40636* 125 2N3053* 20 40673* 68 293054* 49 293055* 55 293108 2N3121 2N3133 39 40 43 33 30 2N3135 2N3250 2N3252 36 2N3302 35 24 2N3442* 131 20 17_ 2N3563 Matched Pair 10p extra. CHOKES SC60 100rnilffA80 957 SAXON ENTERTAINMENTS LTD THE PIONEERS OF MODULAR DISCO/P.A. EQUIPMENT NOW OFFER PACKAGE DEALS AT INCOMPARABLE PRICES CENTAUR COMPLETE STEREO MINI DISCO ROADSHOWS - BUILT IN TO LIGHT/SEQUENCER & DISPLAY STEREO DISCOS SOUND C/W LIGHT SHOW & DISPLAY, TWIN SPEAKERS & LEADS 100 WATT MONO SYSTEM `TWO YEAR GUARANTEE .............. ..._. ,i, Standard 100W £249 or Deposit £57.12 , ... E179.50 Deposit £41.66 . 12 Months