Silicon ChipMarket Centre - September 1994 SILICON CHIP
  1. Outer Front Cover
  2. Contents
  3. Publisher's Letter: Where to now for satellite TV?
  4. Feature: How To Use The TEA1100 Fast Nicad Charger IC by Darren Yates & Leo Simpson
  5. Feature: Electronic Engine Management; Pt.12 by Julian Edgar
  6. Project: Automatic Discharger For Nicad Battery Packs by John Clarke
  7. Project: Build The MiniVox Voice Operated Relay by Darren Yates
  8. Project: An Image Intensified Night Viewer by Leo Simpson
  9. Serviceman's Log: Lightning strikes thrice by The TV Serviceman
  10. Order Form
  11. Project: An AM Radio For Aircraft Weather Beacons by Darren Yates
  12. Feature: Amateur Radio by Garry Cratt, VK2YBX
  13. Project: Dual Diversity Tuner For FM Microphones; Pt.2 by John Clarke
  14. Book Store
  15. Vintage Radio: Building a classic crystal set by John Hill
  16. Feature: Remote Control by Bob Young
  17. Product Showcase
  18. Back Issues
  19. Notes & Errata: Microprocessor-Controlled Nicad Battery Charger, September 1993; 4-Bay Bow Tie UHF Antenna, July 1994; Discrete Dual Supply Voltage Regulator, April 1994; Fast Charger for Nicad Batteries, May 1994; Dual Diversity FM Tuner, August 1994
  20. Market Centre
  21. Advertising Index
  22. Outer Back Cover

This is only a preview of the September 1994 issue of Silicon Chip.

You can view 30 of the 96 pages in the full issue, including the advertisments.

For full access, purchase the issue for $10.00 or subscribe for access to the latest issues.

Articles in this series:
  • Electronic Engine Management; Pt.1 (October 1993)
  • Electronic Engine Management; Pt.1 (October 1993)
  • Electronic Engine Management; Pt.2 (November 1993)
  • Electronic Engine Management; Pt.2 (November 1993)
  • Electronic Engine Management; Pt.3 (December 1993)
  • Electronic Engine Management; Pt.3 (December 1993)
  • Electronic Engine Management; Pt.4 (January 1994)
  • Electronic Engine Management; Pt.4 (January 1994)
  • Electronic Engine Management; Pt.5 (February 1994)
  • Electronic Engine Management; Pt.5 (February 1994)
  • Electronic Engine Management; Pt.6 (March 1994)
  • Electronic Engine Management; Pt.6 (March 1994)
  • Electronic Engine Management; Pt.7 (April 1994)
  • Electronic Engine Management; Pt.7 (April 1994)
  • Electronic Engine Management; Pt.8 (May 1994)
  • Electronic Engine Management; Pt.8 (May 1994)
  • Electronic Engine Management; Pt.9 (June 1994)
  • Electronic Engine Management; Pt.9 (June 1994)
  • Electronic Engine Management; Pt.10 (July 1994)
  • Electronic Engine Management; Pt.10 (July 1994)
  • Electronic Engine Management; Pt.11 (August 1994)
  • Electronic Engine Management; Pt.11 (August 1994)
  • Electronic Engine Management; Pt.12 (September 1994)
  • Electronic Engine Management; Pt.12 (September 1994)
  • Electronic Engine Management; Pt.13 (October 1994)
  • Electronic Engine Management; Pt.13 (October 1994)
Items relevant to "Automatic Discharger For Nicad Battery Packs":
  • 3-10 Cell Nicad Discharger PCB pattern (PDF download) [14306941] (Free)
Items relevant to "Build The MiniVox Voice Operated Relay":
  • MiniVox Voice Operated Relay PCB pattern (PDF download) [06109941] (Free)
Items relevant to "An AM Radio For Aircraft Weather Beacons":
  • Aircraft Weather Beacon Radio PCB pattern (PDF download) [06107941] (Free)
Articles in this series:
  • Amateur Radio (November 1987)
  • Amateur Radio (November 1987)
  • Amateur Radio (December 1987)
  • Amateur Radio (December 1987)
  • Amateur Radio (February 1988)
  • Amateur Radio (February 1988)
  • Amateur Radio (March 1988)
  • Amateur Radio (March 1988)
  • Amateur Radio (April 1988)
  • Amateur Radio (April 1988)
  • Amateur Radio (May 1988)
  • Amateur Radio (May 1988)
  • Amateur Radio (June 1988)
  • Amateur Radio (June 1988)
  • Amateur Radio (July 1988)
  • Amateur Radio (July 1988)
  • Amateur Radio (August 1988)
  • Amateur Radio (August 1988)
  • Amateur Radio (September 1988)
  • Amateur Radio (September 1988)
  • Amateur Radio (October 1988)
  • Amateur Radio (October 1988)
  • Amateur Radio (November 1988)
  • Amateur Radio (November 1988)
  • Amateur Radio (December 1988)
  • Amateur Radio (December 1988)
  • Amateur Radio (January 1989)
  • Amateur Radio (January 1989)
  • Amateur Radio (April 1989)
  • Amateur Radio (April 1989)
  • Amateur Radio (May 1989)
  • Amateur Radio (May 1989)
  • Amateur Radio (June 1989)
  • Amateur Radio (June 1989)
  • Amateur Radio (July 1989)
  • Amateur Radio (July 1989)
  • Amateur Radio (August 1989)
  • Amateur Radio (August 1989)
  • Amateur Radio (September 1989)
  • Amateur Radio (September 1989)
  • Amateur Radio (October 1989)
  • Amateur Radio (October 1989)
  • Amateur Radio (November 1989)
  • Amateur Radio (November 1989)
  • Amateur Radio (December 1989)
  • Amateur Radio (December 1989)
  • Amateur Radio (February 1990)
  • Amateur Radio (February 1990)
  • Amateur Radio (March 1990)
  • Amateur Radio (March 1990)
  • Amateur Radio (April 1990)
  • Amateur Radio (April 1990)
  • Amateur Radio (May 1990)
  • Amateur Radio (May 1990)
  • Amateur Radio (June 1990)
  • Amateur Radio (June 1990)
  • Amateur Radio (July 1990)
  • Amateur Radio (July 1990)
  • The "Tube" vs. The Microchip (August 1990)
  • The "Tube" vs. The Microchip (August 1990)
  • Amateur Radio (September 1990)
  • Amateur Radio (September 1990)
  • Amateur Radio (October 1990)
  • Amateur Radio (October 1990)
  • Amateur Radio (November 1990)
  • Amateur Radio (November 1990)
  • Amateur Radio (December 1990)
  • Amateur Radio (December 1990)
  • Amateur Radio (January 1991)
  • Amateur Radio (January 1991)
  • Amateur Radio (February 1991)
  • Amateur Radio (February 1991)
  • Amateur Radio (March 1991)
  • Amateur Radio (March 1991)
  • Amateur Radio (April 1991)
  • Amateur Radio (April 1991)
  • Amateur Radio (May 1991)
  • Amateur Radio (May 1991)
  • Amateur Radio (June 1991)
  • Amateur Radio (June 1991)
  • Amateur Radio (July 1991)
  • Amateur Radio (July 1991)
  • Amateur Radio (August 1991)
  • Amateur Radio (August 1991)
  • Amateur Radio (September 1991)
  • Amateur Radio (September 1991)
  • Amateur Radio (October 1991)
  • Amateur Radio (October 1991)
  • Amateur Radio (November 1991)
  • Amateur Radio (November 1991)
  • Amateur Radio (January 1992)
  • Amateur Radio (January 1992)
  • Amateur Radio (February 1992)
  • Amateur Radio (February 1992)
  • Amateur Radio (March 1992)
  • Amateur Radio (March 1992)
  • Amateur Radio (July 1992)
  • Amateur Radio (July 1992)
  • Amateur Radio (August 1992)
  • Amateur Radio (August 1992)
  • Amateur Radio (September 1992)
  • Amateur Radio (September 1992)
  • Amateur Radio (October 1992)
  • Amateur Radio (October 1992)
  • Amateur Radio (November 1992)
  • Amateur Radio (November 1992)
  • Amateur Radio (January 1993)
  • Amateur Radio (January 1993)
  • Amateur Radio (March 1993)
  • Amateur Radio (March 1993)
  • Amateur Radio (May 1993)
  • Amateur Radio (May 1993)
  • Amateur Radio (June 1993)
  • Amateur Radio (June 1993)
  • Amateur Radio (July 1993)
  • Amateur Radio (July 1993)
  • Amateur Radio (August 1993)
  • Amateur Radio (August 1993)
  • Amateur Radio (September 1993)
  • Amateur Radio (September 1993)
  • Amateur Radio (October 1993)
  • Amateur Radio (October 1993)
  • Amateur Radio (December 1993)
  • Amateur Radio (December 1993)
  • Amateur Radio (February 1994)
  • Amateur Radio (February 1994)
  • Amateur Radio (March 1994)
  • Amateur Radio (March 1994)
  • Amateur Radio (May 1994)
  • Amateur Radio (May 1994)
  • Amateur Radio (June 1994)
  • Amateur Radio (June 1994)
  • Amateur Radio (September 1994)
  • Amateur Radio (September 1994)
  • Amateur Radio (December 1994)
  • Amateur Radio (December 1994)
  • Amateur Radio (January 1995)
  • Amateur Radio (January 1995)
  • CB Radio Can Now Transmit Data (March 2001)
  • CB Radio Can Now Transmit Data (March 2001)
  • What's On Offer In "Walkie Talkies" (March 2001)
  • What's On Offer In "Walkie Talkies" (March 2001)
  • Stressless Wireless (October 2004)
  • Stressless Wireless (October 2004)
  • WiNRADiO: Marrying A Radio Receiver To A PC (January 2007)
  • WiNRADiO: Marrying A Radio Receiver To A PC (January 2007)
  • “Degen” Synthesised HF Communications Receiver (January 2007)
  • “Degen” Synthesised HF Communications Receiver (January 2007)
  • PICAXE-08M 433MHz Data Transceiver (October 2008)
  • PICAXE-08M 433MHz Data Transceiver (October 2008)
  • Half-Duplex With HopeRF’s HM-TR UHF Transceivers (April 2009)
  • Half-Duplex With HopeRF’s HM-TR UHF Transceivers (April 2009)
  • Dorji 433MHz Wireless Data Modules (January 2012)
  • Dorji 433MHz Wireless Data Modules (January 2012)
Items relevant to "Dual Diversity Tuner For FM Microphones; Pt.2":
  • Dual FM Microphone Diversity Tuner PCB pattern (PDF download) [06307941] (Free)
Articles in this series:
  • Dual Diversity Tuner For FM Microphones; Pt.1 (August 1994)
  • Dual Diversity Tuner For FM Microphones; Pt.1 (August 1994)
  • Dual Diversity Tuner For FM Microphones; Pt.2 (September 1994)
  • Dual Diversity Tuner For FM Microphones; Pt.2 (September 1994)
Articles in this series:
  • Remote Control (August 1994)
  • Remote Control (August 1994)
  • Remote Control (September 1994)
  • Remote Control (September 1994)
  • Remote Control (November 1994)
  • Remote Control (November 1994)
MARKET CENTRE Cash in your surplus gear. Advertise it here in Silicon Chip. CLASSIFIED ADVERTISING RATES VINTAGE RADIO Advertising rates for this page: Classified ads: $10.00 for up to 12 words plus 50 cents for each additional word. Display ads (casual rate): $25 per column centimetre (Max. 10cm). Closing date: five weeks prior to month of sale. To run your classified ad, print it clearly in the space below or on a separate sheet of paper, fill out the form & send it with your cheque or credit card details to: Silicon Chip Classifieds, PO Box 139, Collaroy, NSW 2097. Or fax the details to (02) 979 6503. VINTAGE RADIO SWAP meet/fair. Inc. military, amateur radio and antique sound. Sunday 23rd October, 1994 10am to 5pm. Glenroy Technical School Hall, Melbourne. Bookings: R. Howarth, PO Box 9, Junortoun 3551. Phone (054) 49 3207. _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ _____________ FOR SALE REAL TIME ICE!!! The only way to go. MOTOROLA 6805 EMULATOR and programmers. Prices and data from Graham Blowes, Mantis Micro Products, 38 Garnet Street, Niddrie 3042. Phone (03) 337 1917 (a/h), (03) 575 3349 (b/h). Fax (03) 575 3369. WEATHER FAX programs for IBM XT/ ATs *** “RADFAX2” $35 is a high resolution, shortwave weather fax, Morse & Rtty receiving program. Suitable for CGA, EGA, VGA and Hercules cards. Needs SSB HF radio & Radfax decoder. *** “SATFAX” $45 is a NOAA, Meteor & GMS weather satellite picture receiving program. Needs EGA or VGA plus “WEATHER FAX” PC card. *** “MAXISAT” $75 is similar to SATFAX but needs 2Mb expanded memory (EMS 3.6 or 4.0) and 1024 x 768 SVGA card. All programs are on 5.25-inch or 3.5-inch disks (state which) & include documentation. Add $3 postage. Only from M. Delahunty, 42 Villiers St, New Farm, Qld 4005. Phone (07) 358 2785. Enclosed is my cheque/money order for $­__________ or please debit my RCS RADIO PTY LTD Card No. ✂ ❏ Bankcard   ❏ Visa Card   ❏ Master Card Signature­­­­­­­­­­­­__________________________ Card expiry date______/______ Name ______________________________________________________ Street ______________________________________________________ Suburb/town ___________________________ Postcode______________ 94  Silicon Chip RCS Radio Pty Ltd is the only company that manufactures and sells every PC board and front panel published in SILICON CHIP, ETI and EA. RCS Radio Pty Ltd, 651 Forest Rd, Bexley 2207. Phone (02) 587 3491    Zelcon Technic Pty Ltd • • • • PCB Supplier Photoplotting Services SMT/Through-Hole Assembly CAD facilitites PO Box 149, Glenorchy, Tas 7010 Ph: (002) 71 8120, Fax: (002) 71 8182 BBS: (002) 73 0799 TRANSFORMER REWINDS 350 Watt Power MOSFET Amplifier Module • • • • As published in the June 1994 issue of Silicon Chip. Kit price $159.00. Postage and handling $8.00. Payment by M/C, B/C, Visa, Cheque or Money Order. 3kg O/N Air Bag $10.00 Computer & Electronic Services Pty Ltd 27 Osborne Avenue, Trevallyn Launceston, Tasmania 7250 Phone 003-34 4218; Fax 003-31 4328 MEMORY & DRIVES PRICES AT AUGUST 1ST, 1994 SIMM (all 70ns) Parity/No Parity 1Mb 30-pin $60/54 4Mb 30-pin $208/195 2Mb 72-pin $135 4Mb 72-pin $235/212 8Mb 72-pin $470/415 16Mb 72-pin $900/765 32Mb 72-pin $1690/1590 MAC 6Mb P’BOOK CO-PROCESSORS 387S/DX to 40 $350 $90 LASER PRINTER HP with 2Mb $198 ALL TYPES OF TRANSFORMER REWINDS COMPAQ PROLINEA TRANSFORMER REWINDS 8Mb $476 EPROM & SRAM EMULATOR: 2K x 8 (or 16) to 64K x 8 (or 16). Down­load and verify via standard PC printer port. Supports Binary, Intel and Motorola hex formats. Including Binary Editor. For more information, contact Northern Eastern Digital, PO Box 1252, Collingwood, Vic 3066. Fax (03) 484 5133/432 1063; Phone (03) 432 1699. MICASOFT Electronics and Computing tutor program, written in UK, ideal for TAFE, schools, or individual use. Now available in Australia. Send $1.80 in stamps for demo disk (tell us what size). $7 $8 IBM PS.2 55 x 65 SXVP 4Mb L40/N33 4Mb 90/95 PS1 4Mb $298 $280 $250 TOSHIBA 2000SX 44/6400 $460 $280 8Mb 4Mb SUN SPARC 10/20 16Mb SPARC 10/20 64Mb $975 $4080 DRIVES – SEAGATE 261Mb 16ms 2yr w 528Mb 12ms 2yr w 1052Mb 9ms 5yr w $315 $480 $1170 1st Floor, 100 Yarrara Rd, PO Box 382, Pennant Hills, 2120. Tel: (02) 980 6988 Fax: (02) 980 6991 SUBSTITUTE FOR A HANDFUL OF ICs: Parallax “BASIC STAMP”. A gen­er­al purpose small circuit module, it is really a 25 x 50mm board with a computer chip (4MHz PIC 16C56), EEPROM, 8 I/O pins, board space includes prototyping area. Program it on a PC (only 33 instructions) with development kit which includes one “BASIC STAMP” ($249 plus S/T & post), extra modules ($66 plus S/T & post). Send 45c stamp for more information. Parallax distributor and techni­cal support in Australia: MicroZed Computers, PO Box 634, Armi­dale, NSW 2350. Facsimile (067) 72 8987. 70ns 70ns Sales tax 21%. Overnight delivery. Credit cards welcome. 5-Year warranty. Ring for latest prices. Reply Paid No.7, PO Box 1058, St Marys, NSW 2760. Ph: (02) 833 1146. Fax: (02) 623 5559. SATELLITE TV DX SUPER RX receiver. Threshold 2.5dB. Also digital picture, sound, synchron, resolution processors. Mobile DX re­ceivers, pay TV decoders. TV, radio, picture, sound mod­ulators. Digital, analog signal meters. Send $5 for info and catalog/refundable to John Papp, PO Box 472, Sanderson, NT 0812. Fax/Ph:(089) 27 4985. DRAM DIP 1Mb x 1 256 x 4 PELHAM MicroZed Computers, PO Box 634, Armidale 2350. FLUORESCENT INVERTER KIT (SC, Feb 91) (Soft Technology No. 46): 12V, 24V or 48V/16W version. Secondary wind, board plus compon­ents $30 plus $4 p&p. SOLAR BATTERY CHARGING REGULATOR: short form kit 12V or 24V (SC, Jan 94) 10A $54 plus $4 p&p. Additional Mosfet $8 and Schottky diode $5 to make 20A regulator. With every kit ordered FREE used LEAD SEALED BATTERY 12V/4Ah or 6Ah while stocks last. Good condition but no warranty. Only p&p is charged for battery. Ring for postage cost. Cheques and postal money orders accepted with mail orders. Send orders to: Otakar Priboj, PO Box 362, Villawood, NSW 2163, Australia. Phone (02) 724 3801. INTELLIGENT INFRARED RECEIVER (ref SILICON CHIP, March 94). Now with 8 outputs. Use your TV or VCR infrared remote control trans­mitter to control your TV or hifi appliances with an intelligent infrared receiver kit. Also available infrared transmitters, preprogrammed and learning models. For details call BENETRON P/L (018) 20 0108. MANIPULATE MODELS, Machines, Men or Mice from the serial port (9600, N, 8, 1) of your PC using my PICEX Controller. It’s a tiny computer with its own Operating System controlling 16 I/O lines. Very simple programming language. You can even drive it from any VDU or terminal. Has 3 LEDs, 26pin MAD bus and 34-pin RELAY8 bus. Up to 256 boards can be driven from 1 serial port. Short form kit includes programmed PIC16C57-XT chip, board, 4MHz Xtal, and MAX-232 $70, A&T $130. Promo disk $2. Don McKenzie, 29 Elles­mere Crescent, Tullamarine 3043. Phone (03) 338 6286.    SILICON CHIP BINDERS These beautifully-made binders will protect your copies of SILICON CHIP. They feature heavy-board covers, are made from a dis­tinctive 2-tone green vinyl & have the SILICON CHIP logo printed in gold-coloured lettering on the spine & cover. To order, just fill in & mail the order form on page 79, or phone or fax your order to: Silicon Chip Publications, PO Box 139, Collaroy Beach, 2097. Phone (02) 979 5644. Fax: (02) 979 6503. August 1994  95 Microprocessor For Stereo Preamplifier Now back in stock: the 68HC705-C8P pre-programmed micro­pro­cessor for the Infrared Remote Controlled Stereo Preamplifier (SILICON CHIP, Sept.Oct. 1993). Also suits the Remote Volume Control (May & June, 1993). Price: $45 + $6 p+p Payment by cheque, money order or credit card to: Silicon Chip Publications, PO Box 139, Collaroy, NSW 2097. Phone (02) 9795644; Fax (02) 979 6503. THE HOMEBUILT DYNAMO: (plans) brushless, 1000 DC watt at 740 revs. $A85 postpaid airmail from Al Forbes, PO Box 3919 - SC, Auckland, NZ. Phone Auckland (09) 818 8967 any time. Rotor magnets (3700 gauss) kit now available. VALVE AMPLIFIERS: Australian made. Mono, stereo, guitar using 2A3, 211, 6L6 or 807 valves. Williamson reproductions. Parts available for DIY constructors. Circuit diagrams and construction details for many types of valve amplifiers. Valve equipment repairs. Lancroft Pty Ltd, PO Box 439, Bexley 2207. Phone (02) 567 5390. THE 8051 MICRO-COMTROLLER book includes a simulator disk ($40). ROMLoader EPROM Emulator (EA Jan/Feb 92, EA June 94) (PCB $30). 8051 Proto-Boards (EA Feb 93) (PCB $30). Tantau Australia, PO Box 1232, Lane Cove, NSW 2066. Phone AH (02) 878 4715. SmallTALK for PCs: voice digitiser for 286’s and up Play speech on your PC’s speaker with no sound card! 3 minute version $34.95 HDD version $39.95 Optional QLB/LIB libraries $14.00 All orders add $3.05 p+p. Send your cheque/order to: RAT Electronics AUSTRALIA PO Box 641, Penrith, NSW 2750 Ph: (047) 77 4745 Fax: (047) 77 4745 Altronics ................................ 60-62 Aust. Audio Consultants...............95 Av-Comm................................57,77 Computer & Elect. Services.........95 David Reid Electronics ..............33 Dick Smith Electronics........... 12-15 E. R. Audio...................................96 Harbuch Electronics....................33 ELECTROSTATIC LOUDSPEAKERS 3-PANEL FULL RANGE DESIGN, AVAILABLE IN KIT FORM OR FULLY ASSEMBLED. LOCALLY DESIGNED & MANUFACTURED. FOR INFORMATION BROCHURE, PHONE/FAX (09) 397 6212 OR WRITE TO: E. R. AUDIO, 119 BROOKTON HWY, ROLEYSTONE, WESTERN AUSTRALIA 6111. Instant PCBs................................95 Jaycar ................................... 45-52 Kalex............................................88 L & M Video.................................43 Macservice....................................3 Oatley Electronics.................. 78-79 PC Computers.............................89 Pelham........................................95 Rat Electronics............................96 RCS Radio ..................................94 UNUSUAL BOOKS: Electronic Devices, Fireworks, Locksmithing, Radar Invisibility, Surveillance, Self-Protection, Unusual Chem­ istry and more. For a complete catalog, send 95 cents in stamps to Vector Press, Dept S, PO Box 434, Brighton, SA 5048. Rod Irving Electronics .......... 26-30 PRINTED CIRCUIT BOARDS for the hobbyist. For service & enquiries contact: T. A. Mowles (08) 326 5590. Silicon Chip Software..................23 2.2kVA VARIAC unenclosed $200. 110V 1kVA transformer enclosed $100. Phone (047) 87 8968. SILICON CHIP FLOPPY INDEX WITH FILE VIEWER Now available: the complete index to all SILICON CHIP articles since the first issue in November 1987. Now you can search through all the articles ever published for the one you want. The index comes as an ASCII file on a 3.5-inch or 5.25-inch floppy disc to suit PC-compatible computers and you can use any word processor or our special file viewer to search for keywords. Simply enter in the keyword(s) and the index will quickly find all the relevant entries. All commands are listed on the screen, so you’ll always know what to do next. Price $7.00 + $3 p&p. Send your order to: Silicon Chip Publications, PO Box 139, Collaroy 2097; or phone (02) 979 5644 & quote your credit card number; or fax the details to (02) 979 6503. Please specify 3.5-inch or 5.25-inch disc. 96  Silicon Chip Advertising Index Silicon Chip Back Issues....... 90-91 Silicon Chip Binders....................95 Silicon Chip Bookshop.................73 Silicon Chip Projects Book........IBC Tektronix....................................IFC Transformer Rewinds...................95 Yokogawa................................OBC Yuga Enterprise...........................87 Zelcon Technic.............................95 _________________________________ PC Boards Printed circuit boards for SILICON CHIP projects are made by: • RCS Radio Pty Ltd, 651 Forest Rd, Bexley, NSW 2207. Phone (02) 587 3491. • Marday Services, PO Box 19-189, Avondale, Auckland, NZ. Phone (09) 828 5730. • H. T. Electronics, 35 Valley View Crescent, Hackham West, SA 5163. Phone (08) 326 5590.