Replacing a Powertransformer

Hallo,
I replace the Power-Transformer of my sixtyfive Reverb(2275-65, Tube Phase Splitter model) with the 100-65 Transformer and have thwo Problems with Service Bulletin 4.
What does Ground switch mean?
What does Filament Wiring mean?
I am German(because of translation)...
THX

hello milan,
the filament wiring is that which enables the heaters in your power and phase splitter tubes to work. it heats the cathode so that electrons are emitted for their passage through the grids on the way to the plate. "ground" --your wiring in germany is 1 phase, 250 volts ac, yes? if so, your ground wire would be that which provides a return path for the two "hot legs" of the power system. a ground in an amplifier serves much the same purpose...it sends the negative leg of a device in the amp circuit to the chassis or ground lug to complete the circuit. sorry my descriptions are so brief dude, thats the best explanation I can give you. hope it helps.
ed s

Ed, that's as good of an explanation as you can hope for and it should translate well. I don't have an export schematic here but the explanation serves well for either US or export. Thanks for helping the guy. I have been pretty scarce around here lately. It's nice to see people step up. I've been somewhat of a traitor lately since I've been using my bassman mostly to gig with. I can lift IT. Mike.

no thanks are necessary, mike. the good folk on this site have always helped or a least had a note of sympathy when I needed help. it's just another turn of karma's big old wheel. I was just glad that I noticed this request and, considering the date, wish I had noticed it sooner.
(in re., the Bassman.... we've all had our little sins overlooked a time or two, I'll never rat you out; and having an amp that both sounds good and weighs less is always a bonus for us old farts).
ed