OUTPUT TRANSFORMERS

I had a feeling
That early console was 2 part
1 channel goes to a plug in for the other speaker
If you didn't have the other speaker cabinet 1 channel would run with no load
 
That could have actually contributed to the filter cap failure. With an open primary there would be much less load on the power supply and the voltages would go up as a result. If the cap wasn't rated for it, eventually it would die.

Might be worth testing those tubes too. If the plates had no voltage but the screens did the tubes most likely fried. Screens make a very poor plate, though they will try for a brief moment.
 
Thanks for looking Scott. I’m going to purchase a new matched pair. Did you have to wait 8?weeks build time for the Edcore,s?
 
I received them in 2 weeks, If you order the ones that Gadget ordered, you could use his circuit, from the Dave Gillespie thread, I'm in the middle of a similar build with the 15w transformers, but feedback isn't done yet.
 
honestly I'd be tempted to go after the Pioneer units from BT, and clone the power amp stage from the unit they came from.
 
I had a feeling
That early console was 2 part
1 channel goes to a plug in for the other speaker
If you didn't have the other speaker cabinet 1 channel would run with no load
I saw that on my console but assumed the jack for the other speaker would have a dummy load when the speaker wasn't plugged in to it. My friend wanted the Drexel cabinet so we did very quick disassembly in his garage at night so I didn't have time to explore the finer points.
 
I didn’t have time to look either. I’m going to look at the schematic and see if it shows a dummy load
 
I didn’t have time to look either. I’m going to look at the schematic and see if it shows a dummy load
I figured the dummy would be up at the phone jack. It may not be on the schematic. Or they may not have used one, but that would be poor design, wouldn't it? Even if my donor only has one good OPT (though they both look okay), between the two units you will have one good pair and can use the Edcors for the other.

BTW, if you don't mind me asking, what does it cost for a pair of new OPTs? I've never bought them and don't even know who sells them honestly.
 
The Edcore are approx $45/each but are built to order. They estimate 8 week build time. But Scott mentioned he got his in 2 weeks
 
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