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Topics - Coyote Circle Studio

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Hi all- first off, howdy from Colorado.  This is my first post!  Excited to be a part of it all.

Anyhow, I have been looking at swapping the germanium transistors in a 1969(?) student model with Peterson amp to silicon.  I have done homework and have seen the previous discussions here and on other forums regarding the two output transistors (currently Delco 801522, swapping with MJ15016G) and how to adjust for the different bias needed for silicon (2.7 ohm to 12 ohm resistor).  I am pretty clear on what needs to be done there.

Problem is there is a third germanium transistor mounted to the back of the chassis, no heatsink, just bolted to the wall, that feeds a power supply board mounted vertically on the inside wall of the amp.  Currently it is a Delco DTG-110B, and I would like to also swap it with a silicon.

The one available schematic for the student model, Rhodes service manual figure 11-19, unfortunately, does not contain the power supply.  It references a separate drawing #6803-5 that I have been unable to find.  One helpful tech suggested I look at the 80 watt Peterson power supply schematic, and while it does seem to be close, it is significantly different enough that I cannot really get anywhere with it.  I admit that is probably more a function of my limitations than lack of information contained, but I am stumped nonetheless.

I am looking for any knowledge anyone might have regarding the rebuild of the power supply, what would be an appropriate swap (would another MJ15016G work there also?) and what would need to be changed to accommodate for the swap.  If any of you have any insight or info that you could share I would be quite grateful.

Thanks in advance for any help anyone might have, and again, psyched to be here!

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