Maybe there is a better place or forum to post this that I'm not aware of (if
so, please let me know), but I thought I'd see if anyone had "been there,
done that" before I start reinventing the wheel.
Probably due to having "hardcore homebrewing" in the gene pool, I tend to get
into some unusual projects from time to time. This particular project started
a few years ago when a set of FAR Circuits Sierra boards "followed me home"
from a hamfest ;-) I've been slowly gathering parts (helped by my 95 y.o.
homebrewer dad's "downsizing" when he moved to assisted living) and now it
looks like I may actually have some time to warm up the soldering iron now
I resolved the well-known connector issue (I think) by doing some surgery on a
couple of shorter connectors with a razor saw and splicing them together.
However, I wasn't finding an easy solution to the tuning cap issue, so I
started considering using varactor tuning instead. In researching possible
solutions I ran across "Sierra tech note: VFO harmonics, birdies, and
varactor diodes" that Wayne posted on QRP-L detailing some issues with the
aforementioned items and listing some solutions. After thinking about the
situation a bit, I started wondering if the K1 VFO design could be
used/adapted to the Sierra as I'm guessing the design changes incorporated in
the K1 were at least partly intended to address the issues noted in the QRP-L
So, what's the word? Is this a possibility, and if so, are there any changes
that would need to be made? I figure there would be plenty of room for a
small daughterboard where the tuning cap normally mounts, and it would also
allow moving the tuning knob to the center (where I prefer it - or it could
even allow for a more "radical" layout with top-mounted controls.)
Also, a couple more questions: 1) what would be the best place to pick off a
signal for a counter/display - Q8/PMO line, or somewhere else? 2) Are J310s
suitable for Q3 & Q8 in addition to Q5? Any other hints or suggestions
concerning this project? (Other than that I need to have my head examined HI