[Hallicrafters] SX-100 BFO Setting

[Frederick Bray]

I am finishing up the restoration of my SX-100, but I have had problems
adjusting the BFO as described in the manual.  It is probably my own
fault that I lost the original adjustment.  When I got the radio, I
couldn't the BFO to function, even after re-capping the radio and
replacing the tube.  I assumed that the former owner had mis-adjusted
the coil tuning and tried adjusting it throughout its range to no
avail.  Turned out that one of the resistors in the circuit had
increased in value well up into the megohm range, dropping the voltage
below what was required.

Anyway, after replacing the resistor, the BFO works, but I can't get it
adjusted down to the spec's in the manual.  I figure that I could
probably set it correctly using my HP freq. counter -- which goes down
to 10 Hz. or with a scope.  Unfortunately, I can't find the right point
and/or technique to pick up the BFO signal without loading the circuit
to the point that I substantially change the frequency.

I wonder if anyone has been down this road and can offer suggestions as
to where I might pick off the BFO output so that I can set it to 50 KHz?

Many thanks.

Fred
KE6CD