Probably mentioned this before, but the NC38S will run a watt or so with a
VN10KM in place of the IRF510. I tried it. It worked until I burned the Q2
out by letting the TC2 position sit in a "untuned" or "scroungy output"
position. Very interesting, that.
If the output is not tuned for a seriously clean signal (as side-tone or
scope set), ol' Q2 on my NC38S would go completely bonkers and damn-near melt
the back of the box. I think I've reported this before.
One thing that I have considered (and will probably try once I calm down
again) is to use the output of Q1 in the tx chain to drive a Howes kit 30m tx
board that I have kicking around here as part of a previously side-tracked
project. The Howes takes a VFO signal and can be tuned for a pretty clean
looking output. It is also adjustable from milliwatts to 5 watts (generally)
and does get good reports. Since the Q1/2N3904 deal is really a buffer/feeder
for the 74HC240 transmitter game, I figured that I'd just hose ol' Q1 up to
the Howes and tune it for a nice sig -- with the help of tuning TC2 on the
NC38S.
And yes, my version with an IRF510 also put out well over 5 watts. So maybe
it's the IRF510s that they sell around Dayton what's giving all this fun to
folks like me and Ron. Teach us a thing or two.
73
Nils
WB8IJN &c
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