I just picked up an HP-8654B signal generator with the HP-8655A
synchronizer but I am having a problem with the
combination.
When I try to lock the sig gen with the synchronizer
the synchronizer immediately drops out of lock. I
checked the synchronizer and noted that an increase in
input frequency causes the phase-lock voltage to
increase in the positive direction and a decrease in
frequency causes the phase-lock output voltage to drop
in the negative direction. Similarly, an increase of
the voltage into the sig gen phase-lock input causes
the output frequency to increase and visa-versa.
Needless to say, I have a positive feedback situation,
which explains why the combination immediately drops
out of lock when I try to synchronize the sig gen. I
suspect there must be a switch to change the polarity
of either the synchronizer output or the sign gen
phase lock input but I don't have any manuals and I
tried looking for something obvious, but to no avail.
Does anyone know of any such switch or jumper that would
change the polarity of the synchronizer output of the
sig gen phase lock input?
Thanks for any help.
