We pirates have made the common, ordinary IRF 510 MOSFET work much
higher than the 6M ham band-like at 88MHZ! For several months WSQT
Guerilla Radio(The Squat in DC) was on 87.9 at 10W with a single IRF
510 as the final. Details are in an old post to alt.radio.pirate. We
later went up to a dual 6146 tube final for more range, and are now
relocating because FEMA didn't like our Katrina coverage and whined to
the FCC ,who only seem to trouble us around things like Katrina or the
Inauguration. Four months of 10W and 3 at 40-50W with no trouble, but
1 1/2 weeks of Katrina coverage and they came running! Well,we'll soon
be back, but meanwhile I figured you guys would appreciate some design
info. Never have I found any article on the IRF 510 at VHF, so I did
all my own research.

Although I understand many hams don't like pirates, we read your
newsgroups and manuals to learn how to build decent transmitters that
don't pur out spurs and hash, and I figured maybe you guys would enjoy
a return of the favor.

Anyway, I've gotten 13 watts from one IRF 510, with a little over 1
watt of drive. This is with tuned input and output circuits, not
broadband. I've heard others have broadbanded these things that high,
but I can't possibly see how with all that input C! I've never sen an
article on how they did it, only a comment to my original research data
and article an alt-reaido.pirate.

That 13 watts could in turn be used to apply greater drive to
another 4 of these things either in parallel push-pull(possible
oscillation problems but I've done this with the 2N2222 for a driver),
or with resonant 3 winding combiner transformers. Estimated output: 60
watts if you get it right!

Given that I can make the IRF 510 operate at 88MHZ, it should
operate at considerable greater efficiency and gain(better input Q and
higher capacitive reactance)at 50-54 MHZ. What I want to know is this:
can any of you guys one-up me and get at least 8W from one IRF 510 on 2
meters?

If we pirates can make this device operate at 87.9MHZ, surely one of
you can get it to work at 144! Best thing about the IRF 510-it costs
less than $2 and is available at any Radio Shack!