I won this rig as a prize at a hamfest
and it took a while to get around
to building it, but it was worth the effort. I must commend TenTec for
producing a nearly fault-free set of instructions (some typo's) and for
kitting the parts perfectly, no shortages or extras of anything. And
best
of all, it worked as specified through each construction phase
including
final test and alignment. What a receiver! The 5-pole IF filter is
razor
sharp and even on a busy band like 20M CW it's easy to zero in on a
signal
and not hear much else. Signals are detectable down to less than .1uV.
The AF amp is kind of noisy (hiss) but has tons of clean audio that
overrides it. The big, heavy magnet speaker throws enough audio to be
uncomfortable around if turned up too high. TX power was right around
4W, at 14VDC input @1A (all within spec). I might be able to squeeze
another watt out by tweaking the output matching toroids but didn't
feel it was worth the effort. My only criticism of the design is that
the transmit mixer adjustment is very sensitive and is hard to get (and
keep) the transmit offset where you want it.
I might try some component changes to make this more stable, but it
does work as advertised. I was impressed with the design concept they
used which used the same frequency crystals for the transmit mixer, BFO
and IF filter- very efficient engineering. I would add an RIT on-off
switch and maybe a fine tune, but I understand that TenTec
intentionally omitted a lot of features to keep the kit reasonably
priced and less complicated to build. While some might think that $95
for a single-band QRP rig is kind of high, I'm here to tell you that
you are getting much more than a basic DC receiver and VXO.
