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Old 21st May 2012, 10:58 PM   #51
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Join Date: Jan 2006
Location: SF Bay area
Default Some Pics

Pics of custom power amp using EICO Iron.
The thing tacked to the side in the top left picture might be a aux power supply, but I'm not experienced enough to know at this point.
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Last edited by Victoria; 21st May 2012 at 11:09 PM.
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Old 23rd May 2012, 04:32 AM   #52
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Join Date: Jun 2008
They might be LM317s or such used as a DC power supply for the small signal triodes. Can you read he numbers on the devices? Do they tie to the heaters?
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Old 23rd May 2012, 05:30 PM   #53
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Join Date: Jan 2006
Location: SF Bay area
I was looking at it after taking the pictures and there are only 6 octal sockets showing. I knew that, but the implication of it had not sunk in.There isn't a rectifier tube, so the power supply is all buried underneath. I'm going to have to make a schematic of the amp to understand what is happening. Is there a sensible way to do that or do you just dive in
and stay away from the fridge?

A another problem I have now is that I need to find (be told) what *Octal* tube (or tubes} can go in front of each pair of the 6P3S-E's output tubes (I propose to use).
This tube would be the equivalent of the 6AN8's in front of the KT88 in a Dyna Mark III.
The Mark III is a 6 tube(ignoring the rectifier) power amp also.

I believe it is OK to discuss this amp on this thread as it is about the use of EICO

Is there a site with an English data sheet for the 6P3S-E ? I haven't found one yet.

Any help would be sincerely appreciated.
Thanks, Victoria
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Old 23rd May 2012, 07:39 PM   #54
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Join Date: Jun 2008
Yours is a third order threadjack so I wouldn't be too concerned about that. But if you were to start a fresh thread it might get wider viewing. Up to you.

I start by drawing the power supply on one sheet, the phase splitters and power tubes on a second and the front end on a third. That compartmentalizes things and makes the inevitable revisions less tedious.

I don't have a ready answer for you on the phase splitter or datasheet. Once you get things drawn, the selection of a phase splitter will be easier. LTPs with CCS are very popular around here right now and might be worth investigating.
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