Peavet Triumph 60 Watt C57 Capacitor connection?

[Lostfollicles]

Hi Guy's

I have recently decided to replace all the power caps in my PT60 and discovered that C57 (Seemingly an after thought by Peavey) was connected to the 500 volt side of the H.T. instead of as the schematic (Attached) shows the dropped H.T. via R79 feeding R78 & R83 V5 phase inverter plate resistors and the pre-amp pcb H.T. plus they installed a 100uf 450Volt???

Could someone throw some light on this for me? My thoughts are that someone has replaced C57 with the wrong size at some stage and also put it in the wrong part of the circuit!?
It looks like it should be connected as my drawing attached!?

Also with modern smaller same value capacitor types now availabe, perhaps I could fit C57 onto the actual power pcb?

Regards and thank you in advance

Lostfollicles

[nickb]

Perhaps my eyes deceive me but it looks to me as though C57 is is stood off the 500V supply by R79 on the layout and so matches the schematic. 100uf instead of 22uf won't do any harm.

[nashvillebill]

C57 is on the preamp board. On my amp it was the 22 mfd as shown.

Note there are a couple of mistakes on the schematic. The 508 volt B+ splits off before the R59 dropping resistor, not after. The preamp out J3 connects downstream of R88, not before.

But I didn't notice any other problems around R79, R78, and R83. R78 and R83 are on the preamp board.

edit:

R79 is on the Tube Board, it's R59 that's on the chassis. The screen supply is convoluted, it leaves the power board, goes to R59 and the standby switch, then back to the power board, then into the Tube Board, then on to the Preamp Board.

It is possible somebody rewired your amp and stuck an outboard cap. But C57 should be on the preamp board.

[Enzo]

C57 is in the middle of the preamp board. Looks like someone simply added a cap to your B+.

Afterthought? NO, not likely. Peavey wouldn't mount all the filter caps but one on the circuit boards, then mount one more on the chassis.

[Lostfollicles]

Doh!
Thank you guy's I should have known better shouldn't I?
The strange thing is, it was because that extra capacitor was there and looked from the schematic as if it was stood off the board that I didn't think to scrutinise the layout and check if C57 was in fact mounted somewhere else! Doh!
This brings to mind a saying my dad would say to me! Measure twice! Cut once!!

Thank you again guy's where would we be if not for all your knowledge and expertise?

Kind regards
Lostfollicles