Fixing the burned stuff in the Hiwatt. Mouse damaged AOR

Getting in there to scrub off the carbon showed some forks were full on burned off, toothbrush and meths got it of the soot (put kitchen roll around to catch the spray). The forks weren’t really savable so clipped off the protruding bit and pulled some forks from stripped out valve bases and replaced them. Fired it up after checking voltages, works but some noise and microphonics. Bash about with a chopstick, turned out to be a bad resistor. Every resistor replacement is a a task I begrudge in a Hiwatt due tot he inked joins. Turns out the ink floats on hot solder, so if you are careful it doesn’t all have to go.

Other arrival, amp a mate bought on ebay, shipped right to me for a going over. Good call, its a bit of a wreck, sold as ‘working’:

Mice have eaten the insulation off various wires, kind of hard to get them all in focus. Hoovered out a lot of other mouse evidence. Get to do my favourite task of pulling out a pcb to fix it now.

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Hiwatt DR112 100w 6 channel PA

Today’s arrival. Immediate disappointment as I see a not right power transformer, but seems its still a Partridge one from the sticker, unfamiliar style:

Guts, check out the awesome install work for that new tranny:

Nice bit of burning went on here:

Input neatly clipped out in such a way to make it hard to replace, no idea why:

I’ve lost my box of resistors, which is making doing any work on anything difficult, incredibly frustrating.

 

Laney AOR 50w combo guts.

Another AOR variant, the larger 1×12 combo with 2 EL34.

Pretty big for a 1×12 combo, and very heavy.

Similar deal to the other ones inside. Board mount jacks though.

Other stuff of interest maybe: Side by side shot of an original GEC KT88 and the Shuguang GEKT88 which is highly recommended by other people, need to decide what to put them into.

And does anyone have an clue why several amps I’ve had seem to have blobs of vaseline on the power valve bases? Appears to be there on purpose, was it some sort of old wisdom/fix thing people did?

 

Amp kit

Think I mentioned a plan to make a 6EL34 Hiwatt type thing using Sound City iron from a gutted 120? Anyway, most of the parts have arrived, although undecided on jacks, wire and impedance selector.