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A rough transcript of my interview with Len Edwards, VK7LE. 1993 First struck radio at 12 yrs age. Father electrician had receivers & listened to long wave Los Angeles, Honolulu etc abt 1926 Born 1916 Father paid in kind - remember inductances 2 foot diameter. He got a kit & I built it - a 4 valve set from Boys Own Paper. Crystal set - 7ZL on Keens Curry. Studio in Eliz St between L'pool & Bathurst. Upstairs - Jack Broadbent announcer - velvet curtains. Was right opposite Findlays. Late 1938 job with PMG - temporary mechanic at broadcasting studio. OB at Elwick terrible - handling big speakers. Started work at Electrona carbide works - worked on receivers at night - single mens quarters. Gave regular broadcasts around Snug area every lunch hour using grid modulated oscillator. Lived in fear of PMG vans. Amateur licence in 1939 - 8 months before war. Original log book 7NL & 7MG just licensed too Jack Batchelor, Crosby Walch and another came on broadcast band on Sunday mornings. 7CS Phil? Scott, lived at Bellerive. In PMG until early 42. PMG Research putting experimental rig across Bass Strait 40MHz telephony Stanley Franklin arrays for transmitting & rhombics for receiving. Open wire lines down to shack near cemetery. Later permanent 6 channel link finished about 67-8. To Apollo Bay in Vic Before it finished I set up a 40MHz meteor scatter receiver here & recorded number of reflections per minute. Wrote paper - Grote Reber helped analyse results - published in International Journal of the Solar System. Pen recorder bought from Radio Branch built other gear Talked PMG into keeping 40MHz link going until I had these results. Mainly interested in aerials and propagation. When upper atmosphere atomic explosion at Johnston Island I set up 3 channels WWV 5, 10MHz cut dead & came back over 1 hour. Also have tape of it. War, ABC field recording unit. New Guinea, Singapore, Japan. Presto portable recorder - 3 cases. Acetate disks. Built a recorder 40 lbs in one package. Pinched the recording head off the Presto. Been to NG back in Sydnet for rebuild. Spring driven motor. Re- paired it after shelling. Now in ABC museum. After war to Melbourne research then Hobart. Tape recorders after war. Wire recorders before war - poor quality unreliable. Steel band 1/4" wide good - in Melb? Recorder used ball sliding on disk ahead of cutter to stop dig in due to vibration. Could record in aircraft & ships. Tried coating 8mm film with acetate disk coating and ran reel to reel NBG. Before war had tried disk recording at Stanley. 7ZL & ZR had presto recorder. Only club was Wireless Institute. 7LJ & ? at tech instructor All set to go when licensed. Tried grind crystal from spectacle lens Genders had radio section - sold crystals - bought naked 3.5mHz crystal & made holder from penny. Six months Morse. On phone after war. Fiddled on 50MHz. Gear hard to get and expensive. Morris - The Radio Wrecker for parts & Crosby Walch (expensive but good) Watsons Wireless - Barneys dad. Prewar TRF rx Superhet later First QSL card lino cut by Jack Newman of Specialty Press Started with keyed oscillator 4W to USA. Galv iron chassis' - rack Shack was converted fowl house. Wound own power transformers After war disposals stuff 113A aircraft receiver formed part of 40MHz gear. Still got the ones I built up in the roof tx & rx & wavemeter After war built superhet plug in coils - later switched. Interested in 2M about 1956 mobile with halo - others verticals. SSSC 1954 built think first in Aus Filter system - was never able to work anybody using SSB 2 way. SSB filter powdered iron cores at 455KHz access to PMG instruments point by point tune up. Wrote up in AR 1954 1949. Athol Johnson interested in SSB & Dave Hildyard (phasing rig) [articles by Len in July & August 1949 AR detail a low freq 12.5KHz high pass filter rig] Letter from Byron Goodman of ARRL about it.. 14/7/49. Been using it commercially for some time. Early STC carrier stuff went back to 1920s Looking at photo of rig. Cores ex PMG. I made a crystal for my crystal set lead & sulphur mixed & heated. Crystal set in matchbox tried stringing wire across room but didn't work - need to wind coil to get inductance. Did bit of radio astronomy on 2M. Saw CSIRO setup at Dapto. Built 2M phased array about 12 elements + chicken wire. 6J6 cascode preamp PMG had noise generator & measured. Living in Strickland Ave & trolley buses etc noises killed project. Set beam, ran recorder & took mobile rig around state to see if I could hear myself. No. Could hear sun & galaxy with ra gear. Did some here [Geilston Bay] too, using computer to save results. Also weather fax. Andrew Boone wrote software. Talk about automatic ATUs. We put ATU into the aerial. Retired in 1968 just after thhey put man on moon. I had a rig on a boat - built a centre loaded whip which worked really well. A lot of people saw & wanted one. Max Sidebottom was making a rig aerial was bamboo with wire wound round (7SK). Measured marine aerials by anchoring boat & measuring signal from tx 1 mile away. Sydney uni have antenna range for patterns (scale aerials). Was making lots of antennas myself - long hours. Son came down from Sydney uni & took over. Worked together to develop aerials. [Moonraker] Don't now get involved with business side. Now make HF stuff, wide band wire, 2-20MHz periodically loaded. see Police academy. Marine verticals & untuned verticals with ATUs. Land mobile - short wide band aerial - 2-30MHz? - make an autotune centre loaded aerial. We put ATU in base of aerial - move ferrite - got trip to America out of that. Started off with SWR meter and stepper motor now -?- in receive mode has wideband active aerial for sel-call. We have found several 50ohm resistor wide band aerials. Forgot to mention Scientific and Industrial Exhibition in 1954 - Institute had exhibit - this is setup in hall - ionospheric sounder read out. Tx aerial on City Hall roof, but too noisy for receiving so had 2M link to Mt Stuart - Bill Tate - rx had motor drive for tuning. Here is official program for it. Russian satellites - 20? & 40mHz Bill Watson was working on Domain I got word of publicity too. Took photo at Strickland Ave - Max Loveless fiddled the photo & came up with that - [much laughter] I did a bit of radio class teaching Books - best are Terman & Laport Antenna Engineering. Difficult to find info on LF aerials 300KHz for oil rigs. for NDBs & data Still a market for ships aerials on 400-500KHz. Just after war looked at Tonga radio - best freq was about 4MHz Original 7ZL had 2 valves 18"dia football shaped MOPA - Heising modulation - self controlled oscillator - wavemeter on control desk control freq by opening & shutting door & letting in cold air. When 7ZL went to AWA crystal contol tx 2KW & 7ZR STC. Aerials were T's 2 big oregon poles 7ZL on its own had full flat top. When 7ZR came along used 1/3 on 7ZR & 2/3 on 7ZL. With 2 separate downleads. 7HO has granite ground on hilltop but good signal even at a distance. 7HT originally had transmitter at Mcanns building aerial on roof Went down to Howrah on waters edge but signal poor finally went to Sandford. Max Loveless and I did a lot of field intensity measurements on various sites. 7ZL, 7ZR, 7QN. Tested a lot of sites Ralphs Bay by _far_ the best. Had mobile transmitter 2 60' oregon masts ran out earth radials. Test for a couple of weeks. Measure every 20-30 degrees. A site that looked good often was not. 7QN on Zeehan road. 7ZR interfered with a station in NZ so put in an extra phased vertical. Measurements on water null had to be across Ralphs Bay, so set up on HMAS Huon and did sweep. Devil of thing to tune up. Had to get null not too deep as Peninsula & Orford. Max & I spent weeks of long nights. Also used dinghy for radial measurements. Swamped meter! Showed auto tune whip. 2 - 30 MHz. 2 start thread for quick tuning. Sold a lot of those. Knew what wanted for slug went to NY and they produced one.