'66 Alamo project &nbs

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Zedhead
Posts: 5
(3/4/04 9:06 am)
 '66 Alamo project
--------------------------------------------------------------------------------
 Hello, everyone!
This is my first adventure INSIDE an amp. Info on this amp seems scarce as snake fur--I can't find a schematic--but it is a single-ended, point-to-point wired, single 6V6 combo with vibrato. It appears to be very original; including all the caps and resistors.
There are some weird things under the hood; and I have some questions about what parts I should use for replacements.
(1) An old Mallory multi-can type filter cap labeled 20 MFD @ 450, 20 MFD @ 450, 20 MFD @ 25. I can't find anything even close out there; so I understand I have to get separate caps and wire them together? (The can is soldered to the chassis, and I assume that is a common ground for the caps?)
(2) There are a couple "Ceracap" electrolytic caps, one is .02 MFD @ 600V, the other .05 MFD @ 600V. What would be the best replacement?
(3) There is a small 'brown drop' cap on the input circuit labeled 680/20%. According to the cap code, that would be .000068uf or 68pf. Can that be right?!
I was thinking of changing the input circuit anyhow, so maybe this is moot.
(4) Should I replace ALL the old brown drop caps with something else? Orange drops?
(5) The heater wire is poorly done--run flat across the chassis and very loosely twisted. Problem is that it is too short to re-route. Can I solder/splice a new wire into it--or can it be accessed at it's source inside the power tranny?
(6) Well, this is just a question: how does a vibrato circuit work when there is no optoisolator? Am I correct in guessing that the electrolytic cap with the resistor riding piggy-back creates the effect?
Thank you for your patience and for any ideas/help you can offer. JP
 
 
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