Well, I did a swell job of getting the PS circuit boards all put together,
and mounted, double checked everything, fired it up on 220ac, and the plate
voltage showed at about 1700 or so. Looked at it for 15 seconds, turned 'er
off and switched it to SSB, turned 'er back on and got a big buzz/hum
followed by some rather spectacular white smoke and an internal breaker trip.
Upon examination, looks like two of the new computer grade caps are cooked.
( I had used four per leg so I have two spares out of the ten I ordered. )
Now I have some further troubleshooting and triple checking my work to do.
Looks like the doubler was working ok initially based on the voltage reading.
Haven't thought through yet what would have caused the problem simply
switching up in voltage. Doesn't seem likely to have been miswired diode
strings or I wouldnt have got the decent first indication and voltage reading
on the cw setting. I wonder if its possible to simply get a bad quality cap??
At $9 each you sure wouldnt expect it.
FYI, a lot of oily type stuff comes out of the caps when they burst---hence
the smoke.
Randy
K8BUX
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