Fitting to the page number, todays star is the EG&G / PAR / Ametek
Model 5113 Low-Noise PreamplifierAfter
the incident the two input dual-gate FET 2N5564 were replaced with parts from
Linear Systems and it would amplify small signal AC again - but the overload light was still always lit. Recently a fresh look revealed an huge DC offset and the AD744 opamp as it's likely source.
Today, (how nice!) the replacement arrived and was promptly soldered in place. To my delight, the overload light turned offf! I will have to take a closer look at it to check, if it truly is "like a bought one" now, but I'll sleep good tonight nonetheless
Over the PCB sits a small shield (look closely, it complains!) and a full size metal tray with two flat 12v lead acid batterys for floating use.
Edit: Now to check, if I can find all the case parts again