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RE: Are these military potted trannys?

Posted by Eli Duttman on March 9, 2017 at 18:40:26:
I was overly optimistic in thinking KT88s. The 6L6GC/KT66 suggestion is excellent, given the near perfect fit of Edcor's CXSE25-3.75K O/P "iron". ;>)
http://www.edcorusa.com/cxse25-375k

Add Tubelab's PowerDrive, for a positive g1 regime (Class "A2"), and the capability of the suggested O/P trafo will be utilized. Some magnetic headroom has to be reserved for GNFB, as unassisted UL mode is unlikely to exhibit an adequate damping factor.
http://www.mif.pg.gda.pl/homepages/frank/sheets/127/6/6L6GC.pdf

I double checked the GZ34/5AR4 data sheet. The type is OK fed by 500-0-500 working into a choke I/P filter. :>)
http://www.mif.pg.gda.pl/homepages/frank/sheets/010/g/GZ34.pdf
So, avoid the large 5R4 forward drop and use a 5AR4 to rectify the "tall" B+ rail.

A 5V4, 6106, or 6087/5Y3WGTB is quite adequate to rectify the "short" B+ rail.