DEI GPR-20 manual needed,

[CaptDon]

Greetings, I bought a Defense Electronics Inc. General Purpose Radio
model GPR-20 from an Ebay seller. A couple of minor repairs and it
seems to mostly work. The peak center response of the spectral display
output seems way out of whack with the rest of the radio and the C.W.
function seems to be amiss. The signal meter pins on the high side and
no recovered signal. I would mainly be looking for a manual with schematic
or even just a readable schematic. This thing may be dinosaur technology
as it seems to work from negative 16vdc which usually indicated mostly
all PNP transistors. Thanks for any help/leads!! I will probably cross post
this in the Ham Radio forum also.