The evening started with a stern warning from some rather fierce sounding dude (Big Pete) at the front table, that of the club’s 274 members, about 190 had not yet paid their annual membership fee. (Turns out, I was also one of the naughty ones. I’m gonna have to have stern words with my secretary). Usually when I hear older (or perhaps I should say the “more experienced”) Hams speaking I understand about a half of what they say, or sometimes only a quarter. But at the recent Homebrew evening, I felt like a stilt-legged flamingo trying to select my dinner by dipping my head into the shallows of the Mariana Trench. I was SERIOUSLY out of my depth. I felt like a Minnow in a school of Sharks. Alan ZL3UYJ (and G6UYJ) was first cab off the rank. Golly this fella’s keen. He was first licenced at 15 in the UK and went on to do Engineering Communications at Uni. He’s worked in the field all his life, coming hither in 2003.
He fluffs around with HF QRP at times and has tried a few antenna systems for SOTA portable operation that he copi… um, “inspired by” stuff he saw elsewhere. He’s had a go with beams as well, with a 5 element Yagi on 2 metres and an 8 element Yagi on the 70cm band. In February 2014 he worked DX from Huntsbury Hill on the edge of Christchurch to New Plymouth using just 2.5 watts on VHF. In his spare time, he also potters around with EME (don’t we all !) He was working on an interface for FT8 using USB and access to the UART chip. This would allow the computer to change the frequencies with both the audio and data being handled by the computer. (I’m feeling like a Flamingo again).
Gilbert ZL3GIL then had a turn. As I understand it, Gil has made a dedicated Receiver for the ZL3TEN beacon, on the 10 metre band. Has an RF gain control and the audio tones come direct from the mixer output. Gilbert said “I’ve built several direct conversion receivers over the years, the novelty hasn’t worn off yet”. Next up was Greg ZL3IX. He needed a hand getting in the door with his almighty Yagi, at something like 4 metres long. Designed for 1.296 MHz, and with a transverter of his own design, he was planning on doing a spot of EME before he heads off back to South Africa for awhile. He reckoned he was getting the advertised gain of about 21 dbi, having copied a USA design. He’d even built his own signal testbox around an ADF 4350. Indeed Greg’s talk alone could have filled this whole report by itself, I’ll close with a quote
from him about an excellent technical manual he found, but which is available only, entirely, in Japanese language.
“I can’t read a word of it” he said “but the pictures are really good !” (Fortunately his Japanese wife is able to fill in some of the gaps).
Murray ZL3MH had an IC-202, the “S” mod with USB and LSB in a 2metre and 6 metre transverter. (How come I keep hearing about “transverters”, and what does all the other stuff mean anyway ?) And what on Earth is a Mirage V-108, apart from that it’s 80 watts and has a Crystal Oscillator ?
John ZL3IB spoke words I actually understood. He likes restoring old stuff, he said. He had a current limiting, workbench variable voltage power supply, which ran with an L200-IC at the heart of its circuit. He used some multi-turn pots that he salvaged from something dead at the university long ago, to allow him fine control over the adjustments. He also showed a continuity tester he’d built, to help test dubious cables he comes across. John reckons he’s already restored more than 30 old valve radios, and he still enjoys doing it.
Mark ZL3JVX spoke some words I understood but most interesting was the description of some experimentation which he’d previously done with an old 12 GHz Klystron tube. It was surplus from something on the
West Coast and although he gingerly upped the voltage slowly on a 2kV Variac, there was a “Frankly, enormous great explosion” (or words to that effect, but perhaps not quite so polite !).
David ZL3ASN referred to a 5 watt double sideband AusQRP kitset that has the surface mount components already installed. There was also a capacitor tester and crystal tester, which might have been amazingly fantastic, or was it, as he said, just “the miracle of Chinese marketing” ?
By then my pen was about to run out and my arm drop off from RSI, so that’s all for now.
Photo’s & word’s by Cath ZL3CATH
