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Scott Dorsey · October 16th 14, 10:50 PM posted to rec.radio.amateur.boatanchors

wrote:
Hello,a friend of mine gave me a hw32,unused since 15 years in a
radio club that had stopped its existence ,it was in very bad
condition,with many bad contacts,a total misalignment,and several
burned tubes,I soldered again everything,I replaced tubes,cleaned all
that I could,and after two days of hard work (!!!about 10 hours each
day),all tubes are on,the receiver works well,it is well in the
specified band,with good sensitivity,alignment works well and is
precisely done.But the transmitter gives nothing,the tubes seem
correct ,I substituted them with a hw22 I also have.In you opinion
where should I look?? Voltages around pa are here and correct.

You need two things: the schematic and the scope. Start with the output
of the VFO and make sure that you're actually getting any signal in. I
believe on that radio there is a fixed oscillator, a modulator stage, and
then a mixer where the VFO is mixed with the modulated signal.... make
sure you see something on the scope that looks like RF at each stage along
the way.

Just stick the scope probe on plate and grid of each stage in turn.
Then, once you have found the stage where the problem it, it is voltmeter time.
You're apt to find something like an open resistor or a shorted cap
somewhere... especially if you had a damaged tube, look around the stage
where the damaged tube was found because that's apt to be a place where
something else wrong might be located.

I assume the problem is in all modes? Do your diagnosis in CW mode and
get that working first, then worry about the audio amps and modulator.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."