Fender SCXD power transformer help

[i like guitars]

so i got a super champ xd from a friends brother and the power transformer is dead. can anyone suggest a place i can get a replacement transformer? i got a rough estimate to fix it for roughly $200-250 at a local shop so i thought forget that.

can anyone also explain to me exactly how you drain the caps for safe maintinance.

[mikfer]

If you can, get it to an authorized Fender repair center/dealer. The XD amps don't get fixed, they get replaced.

As for draining the caps. Well, it's a *really* good idea if you don't want a lethal charge going through you when you muck around the with the insides.

Seriously, do a search on this forum for "draining capacitors". Amps are dangerous beasts when not handled properly.

[Cleeve]

If the primary of the PT reads open with a test meter, it's likely the thermal fuse that's inside of the transformer that poohed out.
I don't know your level of tech prowess, but check that, it will involve opening the transformer and testing the internal fuse for open.
I fear that if you need to ask how to drain a cap, this operation may be a bit much, as it involves removing the transformer and removing the end bell, then carefully getting past the insulating tapes inside the transformer in order to find the thermal fuse which is connected in the primary winding via human hair sized (well maybe a little bigger than that) wires. Break a wire, transformer is toast.

The amp will no longer be UL listed if the thermal fuse is defeated. But it will no longer be landfill either! (assuming that is the problem).

[markw51]

Based on the schematic looks to me like there's one power transformer for the high and low voltage power supplies so it is a specially designed power transformer and finding a replacement unless it comes from Fender might be nearly impossible.

[Cleeve]

Any fender dealer could order the TX for you if they wanted to, but most won't be bothered..
I'd try these guys if you reeeely knew for sure that it was the power transformer-
http://www.darrenriley.com/FenderAmpParts.htm

I've seen scores of bad thermal fuses in all sorts of gear, from home stereo to guitar amps to VCRs (remember those?) . If the symptom is an open primary, I'd say it's a 90 percent chance it's the thermal fuse.

[markw51]

Originally Posted by Cleeve

If the primary of the PT reads open with a test meter, it's likely the thermal fuse that's inside of the transformer that poohed out.
I.

Ive been building and messing with various tube amps for years and never knew that power transformers had an internal fuse. That's very useful info.

[Cleeve]

Originally Posted by markw51

Ive been building and messing with various tube amps for years and never knew that power transformers had an internal fuse. That's very useful info.

Only new (post 1990s or so) consumer products have them- I think only for the US market too.. I wonder if re-issues of classics have them?
The thermal breakers are little resistor sized things like you'd find in a hair dryer. The ones in a hair dryer are bigger and better, at least they are supposed to reset, but the thermal gadgets I find in consumer electronics transformers don't seem to do that.

Look at the schematic of the SCXD and you'll see the symbol of the breaker drawn in the primary of the power transformer.

[jays0n]

Is the warranty on the XD not transferable or couldn't the original owner just get it handled that way? Should be 5 years no?

[i like guitars]

Originally Posted by jays0n

Is the warranty on the XD not transferable or couldn't the original owner just get it handled that way? Should be 5 years no?

checked the terms of warranty and the original sales receipt is needed and im pretty sure he doesnt have the receipt anymore. the other problem is since he got it checked at some place that the warrenty may have been voided.

[Billm]

How did you determine that it's the PT? Without the sales receipt, you have no recourse with Fender.

There are no aftermarket replacement transformers for the SCXD. As above, it's a special piece, with filament, high voltage, logic, and solid state bipolar windings. There is not NTC thermistor, but there are several on-board fuses. If the transformer puts out voltages on its various windings, it's probably one of them. If the transformer is truly open, there's no hope without the sales receipt.

The only way to salvage this amp would be to find a Fender service center that would swap you a good transformer from a SCXD with a dead digital section (far more common problem). They could send back the doubly-dead SCXD for factory replacement and you'd be cool.

You can always get one of David Allen's nice little power amps, rip out the circuit board, and build something interesting in the chassis.

[i like guitars]

Originally Posted by Billm

How did you determine that it's the PT? Without the sales receipt, you have no recourse with Fender.

There are no aftermarket replacement transformers for the SCXD. As above, it's a special piece, with filament, high voltage, logic, and solid state bipolar windings. There is not NTC thermistor, but there are several on-board fuses. If the transformer puts out voltages on its various windings, it's probably one of them. If the transformer is truly open, there's no hope without the sales receipt.

The only way to salvage this amp would be to find a Fender service center that would swap you a good transformer from a SCXD with a dead digital section (far more common problem). They could send back the doubly-dead SCXD for factory replacement and you'd be cool.

You can always get one of David Allen's nice little power amps, rip out the circuit board, and build something interesting in the chassis.

the person i got it from got it checked and it was determined to be the PT, i still need to check if he has the receipt. the thing im worried about is that the warrenty may be voided since i have no idea where he got it checked. i noticed that the tubes were changed, so im not sure.

i am going to take it to a authorized service center today to see how much it would cost me.