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Re: What is happening???

69.134.190.5

Hey Grover
I think the Diodes are correct. I only used them on the bias supply. B+ is tubed. I tied the ends with the bar on them to the tranny terminals. I am getting a - 170 vdc reading with the + probe of my DVM attached to the output end of the diodes. I think I have the capacitors right too. For the bias supply the + end is grounded and for the the others the - end. The coupling cap is PIO. Orientation doesn't matter for that oone does it?
For the bias supply I have a 535 vdc/.012 tranny tied into a small variac to control the bias voltage. Do you think the amp rating on the tranny might be too low?
I just flashed on something! I am using tube rectifcation for the B+. When you told me you were using 2x47/500 and 2x100/500 did you mean for the filter caps? I thought you were talking about the other (bypass??) caps off the ends of the el34 and the 6n7. I only have 2 x100/450 at the el34 and 2x47/350 at the 6n7. Could that be the problem?
The coupling cap is a .1/630 PIO. I think it is ok, but maybe I will try another cap in its place.
One other thing I noticed. I used an old acoustic suspension speaker to do the first test run to avoid doing any damage to my khorns if anything went wrong. Everything worked fine as long as I was hooked up to that speaker. When I was finally was feeling that everything was ok I switched over to one of the khorns. It worked fine for several minutes and then that awful screeech happened. This happened twice. I thought I had caused the problem by having the DVM hooked up incorrectly so I started over. Same thing, ok as long as I was hooked up to the old speaker and the screech after a few minutes of being hooked up to the khorn. Is there any chance the loading of the speaker could have any part in this? The old acoustic suspesion speaker is very inefficent.
Sorry about the long post, but I really want to get the bugs out as I really liked what I heard when it was working!
Thanks!
Vince


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