32S-1 10 Meter Align/Tame???

Ian Webb ian_webb at PACBELL.NET
Wed Jun 2 10:21:14 EDT 1999

***HELP/SUGGESTIONS on 32S-1 alignment/tuning???!!!***

It's been 25 or 30 years since I've worked on a 32S-1.  I'm finishing up
with the final alignment of one that I've had completely disassembled.
Up to now all has gone well other than the fact that I set the PTO
frequency with a receiver listening to it and I may have to adjust the
mechanical end points again after completely disassembling and
lubricating it.  It appears to be off about 3 kc.

All of the steps in the manual have gone well UNTIL I GOT TO 10 METERS.
On 10 meters it's obvious that something is self-oscillating as I get
grid current indication without turning up the mic gain at all.  I can
change the grid current by the trimmers but not much and the grid
current is very high.  (Of course, the finals are disabled per the
screen jumper disconnecting and no HV tube in the power supply.)  Even
after I turn the mode switch back off the tune position the meter will
stay high until I switch to another band and then back.

I've taken off the shield cans after this happened as I wanted to make
sure nobody had made any circuit changes inside the cans.  I am aware
the transmitter was used on CB as there was a CB crystal in its matching
75S-1 that transceived with it.  Everything looks fine and I carefully
synchronized the wafers in the cans.

The grid dipper shows that all the circuits will tune to 10 meters as I
rotate the trimmers and the oscillator tank seems to be 2 or 3 MHz high
which I assume compensates for the PTO frequency.  That should indicate
that all is potentially "tuneable" I'd suspect.

I recall from years ago that it's important that the shielding be good
between these stages so I'll bend up some of the "prongs" on the stock
against the chassis to provide good contact before I put the cans back
on those circuits.

Of course I've not reached the neutralization steps yet and since
there's no voltage on the finals there's not feedback from there but the
driver is active.  Should I disable the driver tube and see what
happens?  Maybe measure the output with the HP 410C probe or just use
the GDO as an absorption wavemeter or put the scope on the disabled
driver's grid and see if things still oscillate?  (I have turned the
neutralization caps to see if anything changed and it didn't.)

***Does anybody have any suggestions or tricks of the trade to share
with me before I again tackle this tomorrow?  I'll get it eventually but
it would be helpful to have the guidance of somebody who's been through
this before.  I remember having problems like this on my KWM-2 years ago
and never completely taming and neutralizing it on 10 meters about the
time I became inactive in hamming.  I think 10 meters doesn't like me!!!

THANK YOU for any suggestions you can give me.

Ian, K6SDE

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