Analog Computers

Reference / Paper · 1978

Practical Electronics, November 1978 — Analogue Computer Part 3: Wiring, Testing and Programming

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Third and final construction installment of the Practical Electronics homebrew analogue computer series, covering mechanical assembly into the case, full wiring schedules for eight edge connectors, offset-null trimming and mode-control testing of all ten computing amplifiers, and programming techniques illustrated by worked examples including ramp/square-law function generation, initial conditions, and the spring-mass oscillator. The issue also contains the Moon Landing game article, which independently uses an analogue computer circuit to simulate rocket descent kinematics.

Manufacturer
Practical Electronics
System
DIY Analogue Computer (homebrew, 10-amplifier patch-panel design)
Author
P. J. Kronis, B.Sc.
Year
1978
Type
Reference / Paper
Language
English
Learning track
specific applications
Pages
100
  • DIY Analogue Computer (homebrew, 10-amplifier patch-panel design)
  • Practical Electronics
  • analogue computer construction
  • operational amplifier circuits
  • analogue programming
  • differential equations

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Practical Electronics, November 1978 — Analogue Computer Part 3: Wiring, Testing and Programming

PRACTICAL - NOVEMBER 1978 - .r Australia 85c South Africa 80c New Zealand 85c Malaysia $2.25 for product of date. games, out a new cartridge, cartridge will not go each new and your produced have that ADD up to assemble available, to Just family, vvill be will of easy becomes II your it entre u ar yotl and a video way.White V. colour Teleplay the and date OK on Black orks run. in the long pounds save lay Tele TEL presents EX STOCK PROGRAMAGAf times all of Finished Controls of a Professional I -land games Kit consists of 10 Box "Joystick (1 & 2 The Teleplay Moulded which consists Squash (1 & 2 Inject Solo All one cartridge Tennis, Adaptor. Football, Hockey, Basketball offer Mains We players), Shoot etc. No Special surprised this to yOU all players), pre -drilled --You'll be ONLY are for this holes required. equipmentit is to assemble Manual C2890 + £2.31 VAT TELEPLAY hoW easyn al kit! Instruction at 0.45p. BUILDING p r of essio FUN separately I -1E PROFESSIONAL TVVICE supplied YOU MOST Fully THE GIVES f35.90 PLAYING OFFERED. AND KIT EVER GAME Assembled * * * It * * * * * Main Console has Facility Handicaping Switches. to available become Submarines, will d many game include O a NEVV Wipe ofthese will production INar , 3 months under Space Every already The price £19 depending game. those £12 to more. of the and vary from complexity the NOW upon cartridges 14.90 Hand ntrols t_ + Li. el.14 VAT \at kit - 129° basic + 0.03 VAT' Fully assemble add f3.o0 and with £18.90 with completefollow CartridgesControls already come to available and easy Cartridges Cycle - Controls case instructions. printed as sernbly Stunt Cartridge REALISTIC games Battlelank Race - 2 All par SOUND EFFECTS fully Road Additionalinclude: games Hand Cartridge4 and guarantE 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. BA RC L AYC A RD 1111E743. SHOP OPEN-10am to 7pm - Monday to Saturday / CLOSE TO NEW BARNET BR STATION - MOORGATE LINE YE. welnenrAci:r. All prices include Postage. Watch this page each month for new cartridges, as they become available. Compare our prices with similar products in the big stores, which cost well over £100. EUROPE'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 NOVEMBER 1978 No.15 CONSTRUCTIONAL PROJECTS MOON LANDING GAME by A. Russell Sixty seconds to avoid a negative altitude situation 1138 P.E. V.D.U. SYSTEM -2 by A. A. Berk, B.Sc., Ph.D. Construction and setting up PROXIMITY SWITCH by A. K. Langford A variable sensitivity touch and proximity switch 1146 1160 ANALOGUE COMPUTER -3 by P. J. Kronis, B.Sc. 1165 Wiring, testing and programming WIDE RANGE C/R BRIDGE by W. English 1180 1000pF/10IMS2 GENERAL FEATURES POWER FETs by David Shortland The latest developments in field effect technology 1154 INGENUITY UNLIMITED 741 Supply-Soldering Iron Simmer Control-Auto-Tune Generator-Touch Tuner 1173 NEWS AND COMMENT EDITORIAL EXCLUSIVE OFFER 1137 Two irons at special prices SPACEWATCH by Frank W. Hyde German Satellite, U.S. Satellite, TDRSS, Pioneer Venus 2, TRS, Intelsat Terminal, Spacelab 2 1143 1144 NEWS BRIEFS Starlight Vision Bubbling with Bits-Blinking Good-On the Level! Data Encryption Unit 1153 1170 1182 MARKET PLACE New products SEMICONDUCTOR UPDATE by R. W. Coles A look at some recently released devices STATESIDE SCENE by Dave Coutts New York News SPECIAL SUBSCRIPTION OFFER INDUSTRY NOTEBOOK by Nexus 1179 1182 1185 1186 What's happening inside industry PATENTS REVIEW Thought provoking ideas on file at the British Patents Office 1187 READOUT 1188 1188 A selection of readers' letters POINTS ARISING SPECIAL 8 -PAGE SUPPLEMENT CAR DEVICES Auto-Light-Vari-Wipe-Assisted Ignition System-Intruder Alarm-Battery State between 1164 and 1165 Indicator-Polarity Inverter Our December issue will be on sale Friday, 10 November 1978 (for details of contents see page 1145) 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 November 1978 1121 BLOB -BOARDS DeC-IT and BLOB -IT 111 S - DeC No simpler way of learning circuit construction S - DeC No quicker way of getting circuit working S - DeC Simply plug components in NO SOLDERING S - DeC All components can be RE -USED S - DeC All holes identified by number S - DeC All contact rails identified by raised line S - Dec Complete with project book S - DeC For quick circuit try -outs S - DeC Test Components before soldering S - DeC Large working area S - DeC Test Parts of circuits S - DeC Used in many teaching courses S - DeC Guaranteed life time contacts S - DeC LOW PRICE + 55p £3.78 p&p DeC + control panel + step by step instructions + 9 project booklet + Matching Blob -Board Blob -Board now available in many different layouts and sizes Blob -Board can be used to build any type of project Blob -Board has roller tinned tracks for super soldering Blob -Board has letter numbers on it, no need for layout drawings Blob -Board does not require any cutting or breaking or contact rails Blob -Board components can be re -used and re -soldered making circuit project modifications and amendments fast easy and cheap. Blob -Board is low in price. CODE SIZE mm PRICE ZB5D ZB1 IC ZB2 IC ZB4 IC ZB8 IC ZB8D 92 x 61 114 x 76 115 x 78 127 x 203 254 x 203 165 x 251 £0.44 £0.66 £0.71 £1.90 £3.69 £2.88 All Blob -Board packs contain a project booklet, the "ic" range has a 20 project booklet and "13" range has a 9 project booklet. All prices include VAT Please add 35p p & p minimum order £3.00 Available from all good component stockists A sTRA_pAK All criesinclude V A.T. Add 2 5p 92 GODSTONE ROAD WHYTELEAFE SURREY CR3 OEB over E 100 less 20%. Send SAE for complete list of components 7400 and 7410 SarinTTL 745 74195 012 7400 7401 7402 7403 7404 7405 7406 7407 7408 74008 7409 7410 7411 0.12 0.12 0.12 0.13 0.13 0.21 0.14 0.14 0.13 0.18 7441 0.52 7442 7443 7444 7445 7446 74478 7448 7449 7450 055 090 090 070 015 054 027 027 013 0.29 017 025 020 025 0.21 0.22 021 021 0.46 1.05 0 21 021 071 0.21 0.21 030 034 0.34 021 0.13 030 0.24 0.31 0.24 0.24 0.13 0.26 0.70 0.60 0.60 013 013 013 7481 0.90 0 75 1122 0.21 0.25 7453 7454 7455 7460 7470 7472 7473 7474 73074 7475 7476 7478 7480 7484 7465 021 040 021 7482 7483 0.21 0.21 0.21 028 1412 7413 7414 7415 7418 7417 7420 7421 7412 7423 7425 7426 7427 7428 7430 74530 7432 7437 7438 7440 7451 011 013 016 022 0.70 0.94 0.94 0.94 0.21 0.21 028 013 0.29 0.22 0.26 0.26 0.50 030 026 0.38 0.38 0.42 On a 39 045 071 0.97 0.90 0.88 0.97 7486 74566 7489 7490 7491 7492 7493 7494 7495 7496 7497 74100 74104 74105 74107 74109 74110 74111 74112 74113 74114 74118 74118 74119 74120 74121 74122 74123 74114 74125 74126 74128 74132 74134 74135 74136 74137 74138 74139 74141 74142 74143 74144 74145 74147 74148 74150 74151 74153 74154 74155 74156 74157 74158 /4159 74160 74161 74161 74163 74164 74165 71168 74167 74N 74LSN 026 0.38 1.50 2.00 0.35 0.65 044 040 0.80 0.54 010 0.95 012 0.95 1.05 1.30 2.00 0.94 0013 040 028 0.45 74188 74169 74170 74172 74173 74174 74175 745175 74176 74177 74178 74179 74180 741131 040 040 74182 745182 046 7414183 0 71) 74180 741850 74186 74188 74189 74190 74191 74192 74193 74194 74195 030 040 040 0.00 160 082 1.25 012 0 25 040 0 50 040 005 062 0 59 125 046 046 0.66 0 36 0.69 082 055 040 0.94 062 062 058 200 2 00 2 00 0.64 1.30 1.20 1.15 099 010 010 1.00 0.83 013 013 0.56 1.70 040 080 080 0.60 0119 099 019 2.70 0.90 0.56 1.32 0.96 0.98 0.60 062 E20 less 10%. over E50 less 15%, 745 74LSN 2.10 210 1.69 1.90 4.00 1.11 0.89 0.61 3.25 1.12 I12 1.12 010 012 1.20 1.10 090 1 75 0.75 3 38 230 0.99 1.20 110 115 30 0.98 0.99 0.96 099 110 1.05 1.50 090 200 0.84 e90 010 1.40 1.15 1.15 74198 74199 74221 74147 74248 74249 1.48 1.48 1.50 105 74253 74257 74258 74280 74281 74266 74273 74279 74283 74284 74289 74290 74293 74298 74352 74353 74365 74366 74367 74368 74386 74390 74393 73670 °sr, ,..... 11438014 1643815 LIVION 1.0471114 010 1 30 1.20 045 -14 -14 -14 -14 -14 0 70 0 32 0 32 , 50 _9 0 10 0 65 2 00 0 50 5572701N S5751105 SN76003N SN760135 1.95 1 35 175 S5760335 1045500 1046610 1 95 0 35 T1141205 014 118 1 40 1.15 0.29 2.15 325 043 110 1.25 1.70 0.55 1.05 6.85 392 0.85 1.00 140 1 00 1.05 012 0.52 OAS 012 058 f 92 210 230 0 75 114 78.4810S TCA270S0 TDA2020 2.00 3.20 75414 1.00 OP MAPS 103130 -T099 110 1M301A -T099 0.49 -14 1.00 1M709 -8 0.40 -14 0.42 -T099 050 143,18 043485 LM709 114709 LM741 ,'", 141 inches UNI T 101747 v, 9-95 418-. 4 - f11.35 'Li- flash indePendevn 7 rando, f1135 Sound to Light 600 MASTER UNIT "/A4,1 TYPE A SPOT 'less 1,4,,77/ CHANNEL tift4) r-1 ©0 k? E3on ,5 5,ce-x0r 01411110 -.0 0.30 B C 1,,77,19 TYPE B 3 BANK UNIT -8 022 O TWIN BANK 12 Leff 0.50 8 042 VOLTAGE REGULATORS 111300 -7099 1M3091( -T03 -14 10220 70220 10220 70220 70220 70220 10220 00 30 40 95 85 85 85 70 10 10 BC Fittin g f7.99 E S 1119f7.99 ,11 8pie 01 14 pin 16 pin 012 t 18 ye 0 13 0 23 pie 017 22 ye 0 29 24 pin 28 pin 030 044 40 ye 0 55 UNIT 4. 4 Apif * Length 31 100 WATT SPOT LAMPS RED YELLOW GREEN BLUE CLEAR e 1Z,44: 3 lamps £4 50 I 8 C or E S F.rtni ,401111( V OIL SOCKETS ES f230-. f230 - (less lamps) -14 0.20 -7099 045 -14 0.70 11439005 MC1458P 48723 7805 7811 7815 7824 7905 7912 7915 .11,BC Fitteng Wired ready lu, u Complete with three 100 watt coloured 0 50 51176023N 104741 11A741 - LENGTH 081 110 E565 -14 5E25018 -14 01 220 130 -14 ,,,,,, 1,055, -14 7,1'; ,' 135 112 C43040 " s's. 1-",..-, BANK 6 LIGHT TIestyidIN, RASHERUNIT 115611119CA3045 78A6418 188800 7.20 2.70 747" 74197 74257 andom for P&P (Extra for overseas). D Discounts over E 10 less 5%, over 50 each I ...IPOSTIPACIIi.. Bo C ri gn ,,,,s_ a lex, lamp, E S Kum" F nd 20- for illustrated keit & price A LBEN ENGINEERING CO. LTD.. DEPT. PE THE CRESCENT, WORSTHORNE, BURNLEY. LANCS. Tel. Burnley 20940 Practical Electronics November 1978 Understanding Digital Electronics New teach -yourself courses Design of Digital Systems In the years ahead the products of digital electronics technology will play an important part in your life. Calculators and digital watches are already commonplace. Tomorrow a digital display could show your &SW monelme Coolie me %lows Book 3 Gaits 3 ageforrevix vehicle speed and fuel consumption; you could be calling people by entering their name into a telephone which would automatically look up their number and dial it for you. These courses were written by experts in electronics and learning systems so that you could teach yourself the theory and application of digital logic. Learning by self -instruction has the advantages of being faster and more thorough than classroom learning. You work at your own pace and must respond by answering questions on each new piece of information before proceeding. After completing these courses you will have broadened your career prospects and increased your fundamental understanding of the rapidly changing technological world around you. The six volumes of Design of Digital Systems cost only: £8.10 +90p post & packing And the four volumes of Digital Computer Logic and Electronics cost only: £4.60 +90p post & packing memories, counters and simple arithmetic circuits, and finally to a But if you buy both courses, the total cost is only: £12 4-£1 post & packing complete understanding of the design and operation of calculators and computers. Price includes surface mail anywhere in the world: Airmail extra. Design of Digital Systems is written for the engineer seeking to learn more about digital electroni:s. Its six volumes - each A4 size are packed with information, diagrams and questions designed to lead you step-by-step through number systems and Boolean algebra to The contents of Design of Digital Systems include: Book 1 Octal, hexadecimal and binary number systems; conversion between number systems; representation of negative numbers; com- Flow Charts & Algorithms plementary systems; binary multiplication and division. Book 2 OR and AND functions; logic gates; NOT, exclusive -OR, NAND. NOR and exclusive -NUR functions; multiple input gates; truth HELP YOU PRESENT: safety procedures, government legislation, office procedures, teaching materials and computer programs by tables; De Morgans Laws; canonical forms; logic conventions; Karnaugh mapping; three -state and wired logic. - means of YES and NO answers to questions. Book 3 Half adders and full adders; subtractors; serial and parallel adders; processors and artittimetic logic units (ALUs); multiplication THE ALGORITHM WRITER'S GUIDE explains how to: define the questions, put them in the best order and and division systems. Book 4 Flip flops; shift registers; asynchronous and sychronous counters; ring, Johnson and exclusive -OR feedback counters; random access memories (RAMsi and read only memories (ROMs). draw the flow chart, with numerous examples shown. All that students require is an aptitude for logical thought. Size: A5, 130 pages. This book is a MUST for those with things to say. Book 5 Structure of calculators; keyboard encoding; decoding display data; register systems; control unit; program ROM; address decoding; instruction sets; instruction decoding; control program structure. Book 6 Central processing unit (CPU); memory organization; character representation; program storage; address modes; input/output systems; program interrupts; interrupt priorities; programming; assemblers; computers; executive programs; operating systems and time GUARANTEE sharing. If you are not entirely satisfied your money will be refunded. Logic and Electronic Digital Computer Logic and Electronics - loci 4 NOW (amputee Gook 1 - - £2.95 + 45p post and packing by surface mail anywhere in the world. Airmail extra. r- Cambridge Learning Enterprises, Unit 22, Rivermill Site, FREEPOST, St. Ives, Huntingdon, Cambs. PE17 4BR, England. Please send me the following books: El's sets Digital Computer Logic & Electronics @ £5.50, p & p Digital Computer Logic and Electronics is designed for the beginner. No mathematical knowledge other than simple arithmetic is assumed, though the student should have an aptitude for logical thought. It consists of four volumes - each A4 size - and serves as an introduction to the subject of digital electronics. Everyone can learn from it - included sets Design of Digital Systems @ £9.00, p & p included Combined sets @ £13.00, p & p included The Algorithm Writer's guide @ £3.40, p & p included Name Address designer, execxutive, scientist, student, engineer. Contents include: Binary, octal and decimal number systems; conversion between number systems; AND, OR, NOR and NAND gates and inverters; Boolean algebra and truth tables; De Morgans Laws; design of logic circuits using NOR gates; R -S and J -K flip flops; binary LEARNING ENTERPRISES. HUNTINGDON, PROPRIETORS: Unit 22, Rivermill Site, TELEPHONE ST. PE22 4BR, ENGLAND. DRAYRIDGE LTD. REG. CAMBS. IVES, 67446. OFFICE: RIVERMILL Telephone orders from credit card holders accepted Oil 0480-67446 ST. IVES. (Ansafone). Overseas customers should send a bank draft in sterling drawn PE22 on a London Bank, or quote credit card number. FREEPOST, IVES LODGE, ST. REGD. IN ENGLAND NO. 1328762 Practical Electronics November 1973 enclose a *cheque/PO payable to Cambridge Learning Enterprises (0480) counters, shift registers and half adders. CAMBRIDGE I for £ Please charge my *Access / Barclaycard /Visa /Eurocard / Masterch a rge / Interbank account number *delete as appropriate. Signature 1123 The kits & bits show for the home electronics enthusiast SeymourHall SeymourPlace LondonW1 21-25 November 1978 Seventy stands packed with the gear that the home electronics constructor needs. From kits for keen youngsters just starting - to components for the dedicated enthusiast intent on building his own computer, it can all be seen and bought on the spot in the Seymour Hall this November. Browse through the range of instrumentation, test gear, components and circuit boards. Kits for making everything from an electric grandfather clock to an electronic organ. Build your own microprocessor, construct your own television games and choose hi-fi audio modules for the ultimate in sound! Watch the Demonstrations in adjoining halls - electronic projects brought to life by the experts - and a chance for you to try for yourself the latest ideas from manufacturers and journals. Competitions - Win a microprocessor kit -a frequency counter a 'starter' kit for the kids - and many other daily prizes throughout the show. Open 10 a.m. - 7 p.m. daily. Entrance £1.00 adults, 70p students. Organised by Trident Conferences and Exhibitions Limited, Abbey Mead House, 23a Plymouth Road, Tavistock, Devon. PL19 8AU. Tel: 0822 4671 Telex: 45412 TR ITAV. Clef Products P. E. JOANNA & 'STRING ENSEMBLE' Send S.A.E. for details of Kits & P.C.B.s Please indicate which instrument required. 16 Mayfield Road, Bramhall, Cheshire SK7 1JU NEW/ AMERICAN TYPE CRADLE .u TELEPHONE AMPLIFIER 4r) Our new 1978 catalogue lists circuit board access- ories for all your projects - DIP sockets, pins standoffs, cable clips, hand tools. And we've got circuit boards, module systems, cases and boxeseverything you need to give your equipment the quality you demand. Send 25p to cover post and packing, and the catalogue's yours. VERO ELECTRONICS LTD. RETAIL DEPT. Industrial Estate, Chandlers Ford, Hants. SO5 3ZR Telephone Chandlers Ford (0421512956 1124 ONLY NO f16.95 BATTERIES NO WIRES ONLY +VAT f1.36 Telephone Amplifier with detached plug-in speaker. Placing the receiver on to Latest transistorised - the cradle activates a switch for immediate two-way conversation without holding the handset. Many people can listen at a time. Increase efficiency in office. shop. workshop. Perfect for "conference" calls: leaves the user's hands free to make notes. consult tiles. No long waiting, saves time with longdistance calls. On/off switch, volume. Conversation recording model at L119.95 + VAT £I.60. P. & P. 89p. I 10 -clay price refund on all items. The modern way of in2 -way communistant cations. Supplied plug 3 -core wire. Just socket. into power Ready for use. with £32.99 PER PAIR Crystal +VAT E4.13 communications from room to room. Range 4 -mile on the same mains phase. On/off switch. Volume control. Useful as inter -office intercom. between office and wareclear house, in surgery and in homes. P. & P. 99p. WEST LONDON DIRECT SUPPLIES (PE11) 169 KENSINGTON HIGH STREET. LONDON W8 6SN Tel: 01-937 5548 Practical Electronics November 1978 TTL 74* TT 7400 7401 35 CARDIFF ROAD, 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.. OR BANKERS DRAFT WITH ORDER. GOVERNMENT AND EDUCATIONAL INSTITUTIONS' OFFICIAL ORDERS ACCEPTED. TRADE AND EXPORT INQUIRY WELCOME. P&P ADD 300 TO ALL ORDERS UNDER £10.00. OVERSEAS ORDERS POSTAGE AT COST. AIR/SURFACE. MINIMUM ORDER £2.00 PLEASE. VATare exclusive of VAT, Please add 8% to devices marked * . To the rant add 12.196. 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 7p; 0.0047, 0.0068, 0.01, 0.015. 0.018 9p; 0.022. 0.033, 10p; 0.047. 0.068 14p; 0.10 15p; 0.15, 0.22 22p; 0.33, 0.47 39p; 0.68 45p. 160V: 0.039, 0.15. 0.22 11p; 0.33, 0.47 199; 0.68, 1,0 29p; 1.5 29p, 2.2 32p; 4.7 36p. DUBILIER: 1000V: 0.01, 0.015 20p; 0.022 22p; 0.047 26p; 0.1 38p; 0.4'748p. POLYESTER RADIAL LEAD (Values are in pF) 250V: FEED THROUGH CAPACITORS 1000F 350V 8p 0-01, 0-015, 0-022.0-027.5p; 0-033. 0-047, 0-068. 0-1 7p; 0-15 12p; 0-22, 0-33 13p; 0-47 15p; 0-68 18p; 1-0 24p; 1-5 27p; 2-2 31p. ELECTROLYTIC CAPACITORS: Axial lead type (Values are in pFl 500V: 10 40p; 47 68p; 250V: 100 65p; 63V: 1.5. 32. 50 11p; 63. 100 27p; 50V: 1.0 7p: 50, 100, 220 25p; 470 50p; 1000, 2200 68p; 40V: 22, 33 7p; 3300 62p; 4700 eV 35V: 10, 33 7p; 330, 470 32p; 1000 49p; 25V: 10, 22, 47 6p; 80, 100, 160 8p; 220, 250 1 p; 470, 640 25p; 1000 27p; 1500 30p; 2200 41p; 3300 52p; 800, 1100 4700 54p; 16V: 10, 40, 47. 68 79; 100. 125 8p; 330. 470 16p; 1000, 1500 20p; 2200 34p; 10V: 4. 100 6p; 640 10p; 1000 14p. TAG -END TYPE: 70V: 2000 98p; 4700 1219; 50V: 3000 75p; 40V: 4000 70p; 2500 65p; 25V: 4700 48p; 2000 37p; 40V: 2000 + 2000 95p; 325V: 200 + 100+ 50 + 100 190p. TANTALUM BEAD C4PACITORS 35V 01..7 022 033 047 068 6 8 25V: 15 10 20V: 1.5 18V: 10pF 13p each 47,100 409. 10V: 228F, 33.47 BV: 47,68.100,3V: 68. 1000F. 20p each 10 2 2,.7 47 33 MYLAR FILM CAPACITORS 100V. 0 001 0 002 0 005 001,F 6p 7p 0 015 002 004 005 0 056u7 51,11 2M 0 single gang DIP switch SK() 2M() dual gang stereo SLIDER POTENTIOMETERS 0 25W log and linear values 60rnm 5K0 500K0 single gang 1060 500K() dual gang Sell Stick Graduated Betels 36 each 4p each 6p 0 1" POLYSTYRENE CAPACITORS 10pF to In7 6p; 1 5n7 to 47.1710p. SILVER MICA (Values in pH 3.3 4-7 6 8 10 12 18 22 33 47 50 68.75 82 85 100 120 150.220 SP each 250 300 330 360 390 600 82018p each 1000 1800 2000 2200 20p each 22p 30p COMPRESSION TRIMMERS 4007 10 80pF 25 19007 25p 100-500pF 38; 1250pF 68p top 0 25W 2000- -4 IMO Ven 10p 2.5rnm 3.5mm 23p 319 MONO STEREO - Erie make 5% Carbon High Stability Low noise Me-uaturt. VAL 199 315'2 20-4 "M E24 612 3W 2 20 47M 1W 2 20 10M 612 2% Metal Fern 100-1M0 161/ RANGE meta' 89 lop 8 15p 18p break contacts 200 24p 183P 15pp SOCKETS In Line 2 PIN Loudspeaker 11p 7p 18p 3 4 5 Pin Audio 13p 89 ZOP CO -AXIAL ITV) 146 14p 149 5P W4914 16p 9p 12p Bp double 10p 3 -way I1p 12p 10p assorted colours Metal Screened 4mm 2mm mm WANDER 3rnm 10p 7p 9p 4P 89 All parts available. Send SAE for list. op. 2N5777 45 7 Seg Displays TI L312 C An 3"105 TIL313 C Cth 3"105 TIL321 C An 5" 115 TIL322 C Cth 5"115 DI704 C Cth 3" 99 DL707 C.A. -3" 99 FND357 MAN3640 LCD 3+ digit 120 175 975 I.5p SWITCHES* TOGGLE 2A 250V 2p 5p 60 1% Metal Filrn 510-1M top SOCKETS mouided with LEDs plus clip TIL209 Red 13 TIL211 Grn 18 TIL212 Yellow 22 .2" Red 15 2" Yellow Green19 Spare Clips 2 LS400 255 TIL307 695 ORP12 63 11/ PE DIGITAL THERMOMETER Plastic body PHONO 100 price applies to Resistors of each type 100 not m.ed values PLUGS DIN Bp RESISTORS JACK PLUGS Screened chrome 12p 15p 70p 80p 22p PRESET POTENTIOMETERS Vertical & Hori,ontal 0 1W 50() 5M0 Miniature 25W 1000 3.3M0 Hon, CERAMIC TRIMMER CAPACITORS ;07 4 1507 6 250 8 3007 20p .' MINIATURE TYPE TRIMMERS 607 3 10pF 10 4007 ',07 5 450F 6007 8807 27p 27p 60p 70p 5000. 1K & 2K (lin only). Single 5K 0-2M0 single gang CERAMIC CAPACITORS 50V 151,7 22,4 33oF 47nF ELECTRONICS* Carbon Track. 1W Log & 1W Linear values 01,.7 015 02 9p 50V. 0470E 11p 0 5pF to 10,17 OPTO POTENTIOMETERS IAB or EDEN) 28p 38p 54p SUB -MIN TOGGLE SP changeover 59p SPST on/off 54p DPDT 6 tags 70p SPST DPDT 4 pole on/off DPDT Centre off 79p DPDT Biased 115p SLIDE 250V: in line couplers 12: 18p 22p 1A DPDT 14 DP c/over DPDT 4 pole c/over '114 DPDT 6 Tag ice; 13p 24p PUSH BUTTON Spring loaded SPST on/off 600 SPDT c/over SWITCHES * Miniature Non -Locking Push to Make 150 Push to Break 259 ROCKER (white) 10A 250V SP changeover centre off 30p ROCKER: (black) on/off 10A 250V 23p ROCKER: Illuminated (white) Lights when on: 3A 240V 52p ROTARY: (ADJUSTABLE STOP) 1 pole/2-12 way 2p/2 -6W 3p/2 -4W 4p/2 -3W 41p ROTARY: Mains 250V AC. 4 Amp 45p 7p DIL SOCKETS Sr (Lovv Profile - Texas) 8 pin Op; 14 pin 12p; 16 pin 13p; 18 pin 20p; 20 pin 27p; 24 pin 300; 28 pin 42p; 40 pin 66p. DIGITAL MULTIMETER Announcing DM900 - The Digital Multimeter with a difference - It measures Capacitance too. (as 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. PE VDU SYSTEMS parts now available (send SAE for list) Convert your TV into a VDU by using the new Thomson-CSF. The DM900 is a 3-1- digit multimeter with an TV -CRT controller chip SF.F 0.5in L.C.D. display incorporating: 96364. 16 lines by 64 characters, text refreshment, cursor management on TV screen, line erasing, The prototype accuracy is better than 1%. line end erasing. Compatible with This is a unique design using the latest MOS ICs any computing system. and due to the minimal current drain, is powered £11.50* by only one PP3 battery. There is also a battery SFF 96364E AY -5-1013 UART £4.50* check facility. £8.20. DM900 is an attractive hand-held lightweight 71301 ROM SFS80102 RAM 1K £2.05* device, built into a high impact case with carrying handle and has been ingeniously designed to 74LS163 RAM £0.95* simplify assembly. 120p. SN75450 70p Never before have all these features been offered SN75451 70p. SN75452 to the electronics enthusiast in a single unit. 5 AC & DC Voltage ranges; 6 Resistance ranges. 5 AC & DC Current ranges; 4 Capacitance ranges. Price: £54.50* only (p&p insured add 75p) S. Ready Built units available on order Send SAE for leaflet. (Demonstration on at our shop) Practical Electronics November 1978 SN75454 225p. 2102 LF 2513 74LS132 160p 595p 811_597 1 MHz crystal 95p 109p 323p 7402 7403 7404 7405 7406 7407 7408 7409 7410 7411 7412 7413 7414 7416 7417 7420 7421 7422 7423 7425 7426 7427 13 13 14 14 14 18 38 38 17 17 15 20 17 30 51 30 30 16 29 24 27 27 36 27 7430 7432 7433 7437 7438 7440 17 7441 7442 74 68 115 112 94 94 82 56 17 17 17 17 17 28 25 32 27 38 36 7443 7444 7445 7446 7447 7448 7450 25 40 30 33 17 78 7494 7495 65 57 7496 7497 189 74100 119 74105 82 74107 29 74109 64 74110 54 74111 68 74112 88 74116 198 74118 83 74119 119 74120 115 74121 25 74122 46 74123 48 74125 38 74126 57 74128 74 74132 73 74136 73 74141 56 74142 289 74143 314 74144 314 74145 65 74147 175 74148 109 74150 99 74151 64 74153 64 74154 96 74155 53 74156 80 74157 67 74159 210 74160 82 74161 92 74162 92 74163 92 74164 105 74165 105 74166 161 74167 20 74170 230 74172 625 74173 170 74174 87 74175 87 74176 75 74177 78 74178 102 74180 85 74181 165 74182 160 74184 135 74185 135 74188 275 74190 115 74191 105 74192 106 74193 105 74194 105 74195 74196 74197 95 99 85 75491 75492 75 80 74198 150 75150 110 CMOS* 4000 15 4001 17 17 4002 4006 4007 4008 4009 4010 4013 4014 4015 4016 4017 4018 4019 4020 105 18 87 50 50 18 18 42 86 89 45 89 89 48 99 4021 91 4011 4012 4022 4023 4024 4025 4026 4027 4028 4029 4030 88 20 66 19 180 45 81 99 50 205 100 145 196 4056 134 4059 4060 480 4057 2570 99 4061 2380 999 4062 4063 110 58 4066 4067 380 4068 22 4069B E 20 4070 32 4071 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 4411 21 21 21 23 85 40 21 LINEAR IC'S 702 709C 14 pin 710* 723* 733* 741C* 8 pin 747C* 748C* 753 810 8038CC* AY -1-0212 AY -1-1313 AY -1-1320 AY -1-5050 AY -1-5051 AY -1-6721/6 75 35 48 45 99 22 70 36 150 159 335 580 660 305 208 145 195 385 750 AY -3-8500* AY -3-8710* 21 74 AY -5-1224A* 260 73 AY -5-1230* 450 560 150 AY -5-1315 85 AY -5-1317A 630 82 190 CA3011* 20 105 105 372 110 145 109 109 109 109 110 99 108 720 720 720 CA3020 CA3023 CA3028A* CA3035 CA3043 CA3046 CA3048 CA3075 CA3080E* CA3081 CA3089E CA3090A0 CA3123E MC1303 MC1304P MC1310 MC1312P MC1488* MC1489* MC1495* MC1496 MC1710* MC3401 MC3340P* MC336OP MFC41300B MFC6040* M K50398* 88 260 149 195 99 99 395 92 79 69 150 89 85 97 635 MK50362* 650 MM57160* NE518A* NE555* 620 210 29 60 325 410 410 185 180 MM2102-2* 190 100 MM2112* MM2112-2* 295 NE556DB* NE560* NE561* NE562* NE565A* 223 NE566* 157 190 NE567* 450 71 NE571* 200 RAM2102-2* 210 120 175 RC4136D* 700 70 ROM2513* 295 190 SG3402 175 210 SN76003N 140 375 SN76013N 140 200 SN76023N 170 170 80 175 215 225 115 7451 228 TAA621AX I 111 7453 300 170 TAA960 325 4415F 795 LM301H 7454 70 30 TBA12OS 100 4415V 795 LM301A 7460 220 240 TBA540Q 108 4419 280 LM304 7470 330 110 TBA55013 320 4422 545 LM308 7472 195 TBA64113X11 250 105 4433 1180 LM318 7473 180 79 TBA651 80 4435 825 LM324* 4041 7474 90 80 TBA800 75 4440 1275 LM339* 4042 7475 99 95 TBA8105 94 4450 295 LM348* 7476 4043 70 375 TBA820 4044 88 4451 295 LM379* 7480 48 260 LM380 95 TBA9200 145 4490F 695 7481 4045 86 595 145 TDA1022* 128 4490V 525 LM381 7482 4046 69 320 241 TDA2020 17 LM381AN 4047 87 4501 7483 72 60 125 TL071CP* 58 4502 120 LM382 7484 95 4048 52 50 TL081CP* 4049 48 4503 69 LM 1458* 7485 106 96 LM3900* 60 TL082CP* 48 4506 51 7486 31 4050 130 70 TL084CP* 72 4507 4051 55 LM3909N* 7489 210 198 125 UAA170 72 4508 298 LM3911* 4052 7490 33 90 ZN414 M252AA* 750 99 4053 72 4510 7491 75 130 796 ZN424 4054 110 4511 150 M253AA* 7492 38 375 175 ZN425E* 98 MC724* 4055 128 4512 7493 32 20 30 0C41* 48 ZTX311 13E184* 17 2N3563 9F194 10 0C42* 24 2N3614*169 32 ZTX314 AC117* 35 BC170 17 BF195 10 0C43* 40 2N3615* 135 55 ZTX326 AC125* 20 BC171 11 20 2N3663 24 8F196 10 0C44* 31 ZTX341 AC126* 20 sc 1 72 10 8F197 10 10 0C45* 13 2N3702 20 ZTX500 AC127* 20 BC177* 17 8E198 11 18 0C46* 14 2N3703 28 ZTX501 AC128* 20 BC178* 17 8F200* 28 OC70* 10 19 2N3704 19 ZTX502 AC141* 24 8C179* 17 BF224A 11 18 0071* 15 2N3705 25 ZTX503 AC141K* 38 BC182 9 10 8F244 24 0072* 25 2N3706 30 ZTX504 AC142* 24 10 BF256* 10 50 0076* 36 ZTX531 25 2N3707 8C18313C182L 26 10 BF257* 25 2N3708 0077* 76 ZTX550 18 BC183L 10 8E258* 10 AC176* 26 0079* 76 2N526* 58 2N3709 20 BC184 AC187* 9 BF259* 30 0081* 16 28 2N696* 35 2N3710 10 8F394 20 BC184L AC188* 22 0082* 10 2N3711 45 2N697* 21 ACY17 35 BC186 21 40 8E594 48 2N698* 39 2N3715* 250 0083* ACY18* 40 BC187* 28 8F595 38 0084* 44 2N699* 39 2N3772*170 9 ACY19* 40 BC212 BER39 25 0C122* 48 2N706A* 19 2N3773* 288 10 BFR40 ACY20* 40 BC212L 22 25 0C123* 48 2N707* 50 2N3819 9 35 BC213 ACY21 32 BFR79 28 0C139* 85 2N708* 19 2N3820 11 ACY22* 40 BC213L BFR80 28 0C140* 86 2N914* 32 2N3823* 65 9 ACY28* 40 BC214 BFX29* 26 0C141* 85 2N916* 27 2N3824* 70 10 BFX81* 130 0C170* 78 BC214L ACY39 30 2N3R6fi* 90 40 2N918* ZN3903 18 14 BFX84* ACY40* 48 BC307B 24 0C171* 40 2N920* 51 -18 ACY44 39 BC308 13 BFX85* 24 0C201* 75 2N930* 18 2N3904 18 2N3905 13 8FX86* AD140* 69 8C328 28 OC2O2* 61 85 2N961* 17 12 BFX87* AD149* 70 BC338 23 OC2O3* 85 2N1131* 22 2N3906 AD161* 42 BC441* 30 BFX88* 24 0C204* 85 2N1132* 22 2N4037* 62 17 2N4058 30 42 8C461* AD162* BP/18* 50 TIP29 43 2N1302* 35 17 AF114* 25 BC477* 18 BEY50* 20 TIP29A 44 2N1303* 50 2N4061 11 AF115* 25 BC547 BFY51* 20 TIP29C 60 2N1304* 50 2N4064* 120 11 AF116* 25 BC548 BF052* 20 TIP30 47 2N1305* 28 2N4236* 145 20 2N4289 11 AF117* 25 BC549 BEY71* 20 TIP30A 47 2N1306* 36 65 13 55 BC557 AF118* BSX20* 18 TIP308 64 2N1307* 50 2N4859 42 12 AF121* 48 BC558 85065* 30 TIP3OC 65 2N1308* 46 2N5135 42 55 BCY40* 57 BSY95* 25 TIP31* AF124* 40 2N1613* 23 2N5136 20 AF125* 35 BCY34* 75 BSY954* 25 TIP31A* 40 2N1671* 190 2N5138 AF127* 35 BCY39* 80 BU105 140 TIP3113* 40 2N1671B*195 2N5179* 60 AF139* 35 BCY40* 78 BU205* 190 TIP31C* 66 2N1893* 28 2N5180* 60 75 8U208* 226 TIP32* AF178* 70 BCY43 45 2N1986* 60 2N5191* 65 70 BCY58* 22 E5567 AF180* 65 TIP32A* 49 2N2160* 105 2N5305* 24 50 BCY59* 22 MD8001*158 TIP32B* 70 2N2217* 48 2N5457 32 AF186* 2N5458 32 15 ME4102 AF239* 42 BCY70* 10 TI P32 C* 70 2N2218A*31 32 17 ME6002 ASY26* 40 BCY71* 14 TI P33* 80 2N2219A*22 2N5459 32 17 ASY27* 45 BCY72* MJ400* 90 TIP330* 80 2N2220A*26 2N5485 2N5777* 45 BC107* 9 BCY78* 20 MJ491* 160 TIP33B* 100 2N2221* 23 BC107B* 10 80115* 62 MJ2955* 95 TIP33C* 105 2N2222* 20 2N6027 40 50 9 80121* 95 MJE340* 45 TIP34* 45 40311* BC108* 85 2N2297 BC1088* 12 BD123* 98 MJE370* 55 TIP34A* 85 2N2303* 45 40313* 125 BC108C* 12 BD124* 115 MJE371* 60 TI P34B* 110 2N2368* 21 40316* 85 BC109* 9 813131* 38 MJE520* 46 TIP34C* 110 2N2369* 15 40317* 52 85 BC109(3* 12 BD132* 38 MJE521* 65 TIP35* 219 2N2476* 125 40324 52 BC109C* 12 80133* 43 MJE2955*11 TIP35A* 226 2N2483* 28 40326* 62 BC113 17 80135* 36 MJE3055*70 TIP35C* 270 2N2484* 30 40327* BC114 19 80136* 37 MPF102 30 TIP36A* 265 2N2646* 48 40347* 80 BC115 19 BDI 37* 36 TIP36C* 325 2N2784* 55 40348* 101 36 MPF103 BC116 19 BD138* 36 MPF104 36 TIP41A* 83 2N2846* 140 40360* 43 BC117 15 BD139* 36 MPF105 36 TIP418* 73 2N2894* 30 40361* 45 BC118 19 BD140* 36 MPF106 50 TIP42A* 64 2N2904A*22 40362* 48 50 BC119* 26 60142* 59 MPF107 50 TIP4213* 82 2N2905A*20 40407* 289 BC134 19 80145* 198 MPSA05* 24 TIP2955* 63 2N2906* 18 40411* 63 BC135 20 60222* 60 MPSA06* 24 TIP3055* 60 2N2907* 20 40412* 95 BC136 18 806950* 75 MPSA12 40 TIS43 36 2N2907A*22 40467 8C137 20 BD696A* 75 MPSA55 24 TIS44 45 2N2926G 10 40576* 190 80 8C140* 28 BDY17* 195 MPSA56 24 TIS46 8 40594* 45 2N29260 90 40595* BC142* 25 130Y60* 110 MPSA70 34 TIS50 8 47 2N2926R 65 BC143* 25 130061* 165 MPSUO2* 58 2N2926Y 8 40603* BC147 45 2N3011* 24 40636* 125 7 8F115* 22 MPSUO5 48 TIS62 68 BC148 7 8F154* 47 2N3053* 20 40673* 25 MPSUO6 54 TIS74 BC149 18 2N3054* 49 8 BF156* 29 MPSU52* 65 TIS90 BC153 22 2N3055* 55 14 8F167 25 MPSU55* 53 TIS91 BC154 2N3108 14 BF173* 39 11 25 MPSU56* 56 ZTX107 BC157 10 BF177* 2N3121 40 11 24 MPU131* 39 ZTX108 BC158 11 BF178* 2N3133 43 IN4148 120 ZTX109 11 25 0C25* 4 BC159 33 CR033* 148 11 13 2N3135 BF179* 30 0C26* 150 ZTX300 BC160 30 Zeners 400mw 99 ZTX301 16 2N3250 27 8E180* 20 0C28* BC167A 11 13E181* 2N3252 38 180 ZTX302 18 30 0C29* 2.7-33v 9 BC168C, 12 13E182* 30 0C35* 80 ZTX303 21 2N3302 36 BC169C 10 BF183* 30 0C36* 24 2N3442* 131 99 ZTX304 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 995 4412F1650 4412F1380 SN76033N 70 SN76115N CA3140* ICL7106E* 950 SN76477* ICM7205* 1150 SN76227 TRANSISTORS AC142K* 389 Diodes 1125 MAINS TRANSFORMERS (TM) HITERFORMANCE All have 230/240v 50Hz Primary Voltage 2 amp 5 amp 7 amp 1v 2.4v 4v 6v 6.5v 6.5v 6.5v -0-6.5v 6.5v -0-6.5v 6.3v -0-6.3v 6.3v 8.5v Our Ref. TM 1 TM 2 TM 32 I amp TM 3 TM 37 amp 200 mA TM 21 100 mA TM 21 750 mA TM 7 100 mA TM 33 2 amp 1 amp TM 4 TM 12 8.5v + 8.5v sep. winding 1 amp 9v 9v 9v 9v 10v TM 12 TM 5 TM 6 3f amp TM 11 5 amp TM 38 25 amp TM 15 4 amp TM 50 121 amp TM 15 TM 9 1 amp 100 mA TM 21 I amp TM 7 1 amp TM 10 50 mA TM 19 1 amp 'c' core 1 amp 10v -0-10v 10v -0-10v 12v 13v 13v 12v 12v -0-12v 12v -0-12v 1 5v tapped 9v 17v 18v 20v 20v (with 6v f amp) 20v 20v 20v -0-20v 24v 24v 24v + 2v 7 amp 24v 25v 26v 30v 37v 40v 40v 40v tapped @ 30v. 20v & 10v 40V -0-40v £1.94 £1.62 £2.70 .85 .85 £1.62 £1.62 £2.16 £1.62 £1.89 £1.62 £1.62 £1.62 £1.89 £2.70 £3.24 £4.86 £3.78 £4.86 £1.05 TM 12 TM 13 TM 14 TM 50 2 amp TM 46 6 amp 121 amp TM 15 6 amp TM 15 11 amp TM 16 TM 17 2 amp £3.78 £4.32 £4.86 £4.86 £2.12 £2.70 2 amp 4 amp 11 amp 2 amp 8 amp 37 amp 3 amp 5 amp TM 41 TM 11 TM 39 TM 40 TM 18 TM 39 TM 15 TM 34 TM 46 TM 48 TM 15 2f amp TM 48 6 amp .40 .40 .45 .40 .50 .60 £1.25 £1.25 £1.25 .50 .40 .50 .50 .40 .50 .50 .50 .50 .50 E1 .62 £2.16 £1.89 £1.62 £3.24 £2.70 £1.62 £1.90 £1.62 1 amp 2 amp 1 amp 2 amp 5 amp Post .40 .45 .60 .40 .40 .40 .40 .45 .40 .50 Price £1.25 £1.25 £1.25 £1.25 .60 .60 £2.97 .70 £3.78 .80 £2.43 .60 £2.98 .60 £4.86 £1.25 £31.86 Enquire £4.32 £1.25 £5.02 £1.25 £4.86 £5.02 £1.25 £1.25 ELECTRONIC IGNITION UNIT ... Good for your car and your pocket Fit one today SAVE,SAVE,SAVE! Why pay more when you can enjoy the advantages of true capacitor discharge ignition (CDI) at virtually pre -inflation prices? The benefits to your car and your pocket are enor- mous - easy starting in the coldest of cold weather, an end to burnt contacts and arcing problems, better engine wear and petrol consumption and, of course, easy and secure fit- INC. POST FREE IN U.K. - 75v -3 amp £4.86 £11.65 £1.25 £1.75 £4.32 £7.02 £1.25 £2.50 £8.10 £7.02 £2.00 £2.50 with 6.3v shrouded 75v TM 23 4f amp TM 24 80v tapped 70v & 75v 4 amp 80v centre TM 24 tapped 100v 100v -0-100v 200v 2 50v-0-2 50v TM 25 TM 25 TM 25 £5.02 £7.02 £7.02 £7.02 £1.25 £1.75 £1.75 £1.75 TM 36 TM 36 TM 36 TM 26 £3.78 £3.78 £3.78 £3.24 £1.00 £1.00 £1.00 £1.00 TM 43 TM 49 TM 30 TM 45 £6.50 £4.05 £7.02 £4.05 £10.26 £2.00 2f amp TM 48 1 amp 1 amp 1 amp with 6.3v 2A 50 mA 250v 100 mA 500v 50 mA 260v 60 mA 1000v (and other secs) 60 mA 4 Kv 5 mA 5 Kv 5 mA 8 Kv 5 mA 8.5 Kv 10 mA TM 31 £7.02 £2.50 .70 £1.00 £1.00 £2.00 Full range of Mains to 120v Auto -transformers available Why be AND £6.30 £3.60 £2.30 £7.20 £5.75 £4.90 £2.75 £2.15 £1.90 £1.75 £1.45 £1.30 £1.15 (630 tie points, 4 binding posts, 4 x 14 DIL capacity) P13-100 (760 tie points, 2 binding posts, 10 x 14 DIL capacity) PB-101 (940 tie points, 1 binding post, 10 x 14 DIL capacity) PB-102 (1240 tie points, 1 binding post, 12 x 14 DIL capacity) PB-103 (2250 tie points, 4 binding posts, 24 x 14 DIL capacity) PB-104 (3060 tie points, 4 binding posts, 32 x 14 DIL capacity) PB-203 (2250 tie points, 4 binding posts, 24 x 14 DIL capacity; built-in regulated 5V d.c. power unit) DIY KIT FACTORY FOR INSTANT RETURN TO ORDINARY IGNITION NEG OR POS EARTH MODELS £17.20 £22.95 £34.45 £45.95 £55.15 £74.70 Design Mate Instruments £12:75 DM -1 £45.95 DM -2 £57.45 DM -3 £57.45 DM -4 £74.70 MI HEAVY GAUGE ENCLOSED METAL CASE BUILT FOR YEARS OF DEPENDABLE SERVICE FULL 12 MONTHS GUARANTEE STIRLING SOUND 37 VANGUARD WAY, SHOEBURYNESS, ESSEX. Tel: 1037081 5543 Shop - 222/224 West Rd.. Westcliff-on-Sea. To Stirling Sound, 37 Vanguard Way, Shoeburyness, Essex. ADDRESS £11.80 COM PLETE Pay by Access or Barclaycard if you wish Please send £9.20 IC Test Clips MADE IN OUR OWN U.K. SWITCH £3.16 Quick Test Series PB-203A(As PB-203 with 5V and 15V d.c. power supply) without? NAME SOUTHERN TRANSFORMERS 103 TAMWORTH ROAD CROYDON CR9 1SG V.A.T. READY BUILT ONLY £14.95 shrouded TM 22 50v 8 amp TM 29 60v tapped 40v & 20v 2 amp TM 46 70v 4.5 amp TM 24 £5.75 PB-6 will send a free copy of our unique booklet 50v -2 amp with 6.3v EXP300 (6 x 2.1 in., 5 x 94 terminals & 2 bus strips) EXP350 (3.5 x 2.1 in., 5 x 46 terminals x 2 bus strips) EXP600 (6 x 2.4 in., 5 x 94 terminals x 2 bus strips) EXP650 (3.6 x 2.4 in., 5 x 46 terminals x 2 bus strips) EXP4B (6 x 4 in., 2 bus strips only) Protoboard Series and To all customers this month we "TEST EQUIPMENT" Experimentor Series QT -59S (6.5 x 6.2 in., 118 terminals) QT -47S (5.3 x 5 in., 94 terminals) QT -35S (4.1 x 3.8 in., 70 terminals) QT -18S (2.4 x 2.1 in., 36 terminals) QT -12S (1.8 x 1.5 in., 24 terminals) QT -8S (1.4 x 1.1 in., 16 terminals) QT -7S (1.3 x 1 in., 14 terminals) QT -596 (6.5 x 6.2 in., 20 terminals) AT -47B (5.3 x 5 in., 16 terminals) QT -35B (4.1 x 3.8 in., 12 terminals) ting to your vehicle. ORDER NOW WHILE WE CAN HOLD TO THESE PRICE