[Boatanchors] HW-32 TX instability

[Ian Wilson]

I recently acquired a HW-32 20m monobander. Originally I was using too high
LV+ (didn't
realize the tap in the HP-23 was set to 'high'). Attempts to tune showed
either no output
or 100W of self-oscillation as the Final Tune control was varied. I am using
a 50 ohm
load (and have checked that this is connected to the PA output when the
relay is in the TX
position).

Lowering the LV+ to something more reasonable (around 250V) tamed the
oscillation, but
the Tune function doesn't work. I know about the Drive Level adjustment (and
the Carrier Null
balance control). Increasing the LV+ somewhat moves the PA closer to
instability (e.g.
inserting some audio causes the PA to start oscillating).

With the lower LV+, I see some output

I am going to disconnect the HV and remove the finals so I can work on this,
but does
anyone recognize these symptoms and/or have suggestions? I plan to replace
the bypass
capacitors around the driver and PA tubes.

73, ian K3IMW