Kelly, IMHO you need an independent measure of the plate voltage,
rather then assuming that the voltage divider network in the amplifier
is giving you the correct reading. If you don't have an HV probe for
your DMM then you should probably add one to your tool collection.
While you have the amplifier apart, it's also a good idea to replace
the HV electrolytics.
73,
Jim w8zr
Sent from my iPhone
> On Jul 21, 2017, at 9:48 AM, Kelly Taylor <ve4xt@me.com> wrote:
>
> Update: just checked the transformer primary: appears to be fine (both
> halves).
>
> Put it back together and turned it on again, and was surprised to see Vp now
> at 1700 volts, then realized that was in SSB, so it's still 1kv low.
>
> At 1700 volts, I can get about 600w on 40,20 and 15. Which, accounting for
> efficiency, is probably right about what you can expect for 1kw DC.
>
> So am I right in thinking all signs point to the HV circuit? Something in the
> voltage doubler? Could a leaky bypass cap (which is upstream of the ‘fuses’
> (a pair of 1 ohm resistors paralleled and in series between PS and plate
> choke) drag down the voltage?
>
> (In case you’re just arriving in this thread: yes, the primary circuit is
> wired correctly for 120v; no, the circuit board has not been rewired to
> accommodate 811s, no fuses blow and no smoke has been released (yet).)
>
> 73, kelly, ve4xt
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