"Michael Black" wrote in message
ample.org...
On Thu, 24 Jul 2008, Tio Pedro wrote:

That's the one that's sort of a clone of the S-38?

Michael VE2BVW

It is the clone of the HE-10, which looks like the S-38

I added a voltage regulator, which stopped the oscillator
pulling problems when running the IF gain up and down
(thirty volt swing!). I did a few other simple mods to
get rid of residual hum in the headphones (ground loop
on filament grounding and added one more filter stage
in the PS.) But this drift has me stumped. I tried a
few different osc. circuits, but the design is weird.
It is basically a BS Hartley, except on the highest band
which requires a feedback loop back to the plate to
get it into osc. I suspect it is the nature of the beast.

Pete