I've been trying to restore an SX-117 and HT-44 to use as
a vintage setup. Its been a challange! Seems that everything
that could go wrong has, and in ways that have driven me nuts.

One of the last issues is with the HT-44. The output stage
wants to break into oscillation at (about) twice the freq
its tuned to. I have been unable to neutralize the finals.
The tubes are good (and matched), band switching has been
checked (switches and coils), bypass caps, etc. Everything
looks OK. All of the obvious stuff has been checked (biasing,
power supplies, etc).

Hopefully there is someone out there that is familar with
the HT-44, and may have seen this problem and found a
solution. Nothing useful was found with a google search.

Steve