Hi all,
I have in my possession this amplifier. The conversion was done by an unknown
ham in NC. The conversion includes a filament transformer. Alas, I have a
problem.
First off I'll list the items I addressed after the amp blew the bias supply
cap.
I have replaced the diode, resistor, and cap for the bias supply. Diode and
Cap. were bad.
I have also replaced all diodes on the power supply side of that board. Saw
arcing so I replaced them.
I also found two of the rectifier caps bad and replaced all six.
Now my dilemma,
When I plug in the unit the fan comes on, filaments light, meter lights, and
meter shows 1500V in the HV position without the power switch being engaged.
When I engage the power switch, the fan turns off and filaments go out, the
meter light brightens and the meter shows 2600 V.
Interestingly enough, right after I replaced the components above, the amp
worked fine...and then I pwoered it back up to get these results.
Where is my next turn, I think I may have to draw a new schematic on this
thing, but don't have the time right now.
The amp used to make 600 watts output easy, I ran it at 550 watts out on the
Bird due to transformer weakness in a 572b application. Any help will be
greatly appreciated.
Tnx es 73,
Cam
WA4JKW
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