Looking back in my notes, the diode-based generator idea was from K5OE, where he put a 1N4005 diode in parallel with five 47K 1/2 watt resistors (so, all 6 in parallel), driven at 29.999 mhz directly from his HF rig. I did the same from my 2M HT, and it seemed to work. Also a lot more portable. No clue what sort of return loss it presented, but the HT survived just fine.
http://home.wavecable.com/~ko6th/Dsc00067.jpg
I also tried using a 50mhz crystal oscillator module connected directly to a small 13cm ground plane antenna. That worked too, though the signal was much quieter (48th harmonic).
Greg KO6TH
Zach Metzinger wrote:
That's a great idea on the 2m rig as an exciter for a diode comb generator. I'll have to try that out tonight on my unmodified unit! I assume that you attached the diode on the other side of a 20 dB pad to give some sort of reasonable return loss for the rig?