Hmmm... That can't be good!

[avionic]

Piece of cake Redboy....:thmbsp:

 

[Redboy]

I think so, is it PP?For the OPTs you should be able to measure "some" resistance from the center tap to each tail, then tail to tail should be twice that. On the output side you should get "some" resistance from common to 8ohm, common to 16 ohm, etc. This should let you know if a winding is open,

This is looking pretty good so far. Tail to center was 93ohms on OPT#1, 91ohms on OPT#2. Tail to tail was 182ohms on OPT#1, 182 on OPT#2.

then I would check resistance from each lead to the lamination stack. That will tell you if anything is shorted to the stack. Why don't you post your readings here too.

"the lamination stack." Anywhere on the laminations? I'll need to scratch through a little paint to get conductivity, won't I? So far, no resistance...

 

[Redboy]

Just looking at that, the resistor that cooked goes right off one side of the filter cap. I'd bet you a donut that filter cap is shot, and it probably took out the resistor. Whats the other end of it connected to, one of the rectifier tubes? If so, that would make sense.

That looks like the likely scenario.

 

[jaymanaa]

Sounds like you better get a parts list together.:thmbsp:

 

[Redboy]

Yee haw! I've been using Kiwame carbon film resistors a lot in new scratch builds. I like the small size, tight tolerances, and printed values. Any opposition to these in this amp? This is a Pilot SA-232, BTW.

 

[ejfud]

Good news! I think you'll have a keeper when you get it back up and running.

Going to be tough to beat the 2A3, but this will have a different sound and you can never have enough amps that sound different IMO.

 

[westend]

"Experentia docet". I'm sure you can unravel that. Maybe another scratch build like the Manta configuration you did. I might have missed it but did you ever get the heater problem solved with that?

 

[Redboy]

Not yet. Don't tell Gary - it's his amp...

 

[jaymanaa]

Why is it allways "other" peoples amps that give us trouble? I'm doing one for Rexeverything that is the most simple circuit in the world and it's been kickin my ass (off and on) for two months. I used to use pretty much all metal film but have just recently started using carbon film (Harbor Freight has a hell of a deal on them). I think I'm going to start using some of each type to try to reap the benefits of both. I'm sure carbon will do fine in the Pilot, I think it hard to make one of those sound bad.:thmbsp:

 

[ejfud]

Harbor Freight resistors? Dang they do have it all.

 

[jaymanaa]

Yep, right here http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95860

If you order (2) the number of little drawers comes out right on the organizers. They're actually pretty nice resistors.:yes:

 

[specialidiot]

that'll buff right out

 

[cademan]

You know, a shorted filter can will do whach ya all see there! Replace that filter cap and new resistor then take ohm readings before powering up. Also check that rectifier tube. A shorted one will also cause that damage.

 

[WhiteSE]

Pilot 232 is supposed to be a great amp...good luck, and them PM me a price.

 

[cademan]

Hey guys, a shorted filter cap will cause wot ya all see there. Replace that filter and that fried resistor (not sure how many ohms it is off the top of my head) then take voltmeter readings before powering that thing up. Also check that rectifier tube. a shorted tube will do the same thing. I'm guessing that it's a 5AR4/GZ34. The outputs transformers are likely 99.9% OK and that amp doesn't look all that fried, should be a keeper.

 

[westend]

Yep, right here http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95860

If you order (2) the number of little drawers comes out right on the organizers. They're actually pretty nice resistors.:yes:

That's a heck of a deal. I've seen the organizers, alone, sell for close to that. Here's another one with terminals:Terminal organizer. How are they on shipping prices?

 

[avionic]

shipping charges at HF
http://www.harborfreight.com/cpi/ctaf/aboutus.taf?f=terms

 

[Redboy]

Crud.

The trannies are toast after all. Not because they don't measure well, but the leads are totally cooked and brittle. I took them off the chassis tonight and the wires disintegrated. Took off the bells wondering if I could put new leads on somehow, and it's crispy critters inside too...

This one just wasn't meant to be.

 

[ejfud]

Man that sucks.

 

[currituckco]

Sad news!