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previous: Bruce Greg ... all things being equal, li... -- 1/26/1999 10:33 PM View Thread

Re: Alright, How about this......

1/27/1999 8:41 PM
GregRe: Alright, How about this......
Well, I lifted the 33k resistor from ground and that killed the bias voltage. Nada. Zilch. Nothing. I've put it back now and I've replaced the selenium "turd" w/ a 1N4004. Didn't have a 4007 and since Doc mentioned a 4004...yada, yada. Now, the voltages look this way: Plate = 489v, bias = -42v after the rectifier, -32v after the 10k resistor. That's a far cry from the -70vdc you mentioned, eh? And I got .98v on the cathodes. Oiy.  
Also, I now realize I misunderstood when you typed "use a 10uf/100v to 100uf/100v E-cap..", thinking you meant to use these two values in series. You're just saying to select one cap within that range, yes? It has a brand new 10uf in it now.  
Can you make anything out of this? Maybe I should swap out the other two diodes that make up the B+ rectifier? But does that sound like it has anything to do w/ my problem?  
Thanks again for your input.