Finally after 15 years, Murphy hit me. During an extended round of cq-ing, the
alpha started buzzing loudly in step with the keying. HV, grid-current, power
output all normal. Something started to burn.Shut the amp down and opened it
up...the 25k-25w brown resister on top of the capacitor bankmight have
overheated since the enamel seemed to be flaking off, exposing the wiring...I
temporarily replaced it with a 25ohm-25 watt precision resistor (gold). The
smoking stopped, but the buzzing was still there and I received a bad tone
report. Unless I am wrong, I suspect that I might have a filter capacitor
problem. There is a bank of 6!. Questions....
1. Anything else I should be looking at?
2. How can I tell if it is one cap or the whole bank?
3. Alpha talks about matched sets of caps
4. Where can I get 210 mfd@ 450v without calling Alpha?
5. Assumming it is the bank of caps and I need to get replacements from Alpha,
does anyone have the telephone number for Alpha Power and how efficient are
they in sending out replacement parts?
Well, these questions will do for now...Unless I can get things fixed quickly,
n2mm may be off for future tests...
73
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