I patched up some mechanicals, changed the 6X5 rectifier, checked the main cap and fusing [still worx] .. put on a safe 3-wire mains cable - securely anchored etc ...
voila ... superb stand alone measurement box for 'high amplitude ac signals' with safe 'dc blocking' and fine, fine 'attenuator mit meter' ... my mods re the 'WCF output + traffo' .. to R E W is once again - the icing on the buds.
I can't even imagine what the original 'designers and builders' of this classic piec of kit would make of my 'mods' and most mind-blowing-ly of all .. the crazy good capabilities of R E W and a '100usd interface'.
Dang we have it good!
And just for interest [what else!] .. here are some of the fine Trimax EL34 amps, of which sadly I was not 'savvy' enough, early enough to secure :-X Once they were 'dumpster specials', then they were 'cheap but sought after'.
Now they are in the monied 'waybeyond' - permanently :'(