suitable replacement power supply

[bluesplay]

Can someone tell me what a suitable replacement power supply would be for my behringer gx 112 Blue Devil. I've searched everywhere and can't find it (pcb 125010 REVK/04). This is the one with the LM3886T Audio Amp. Behringer says they don't have any of these power supplies in stock and aren't manufacturing them anymore.

Thanks,

bluesplay

[Amp Kat]

Are you sure it's the power supply ? Something could be shorted dragging it down and would behringer give you a price to repair it ?.

[bluesplay]

Are you sure it's the power supply ? Something could be shorted dragging it down and would behringer give you a price to repair it ?.

I'm certain it's the power supply. I can disconnect the load and still blow a fuse, and I if I disconnect the transformer and power the switch the fuse does not blow.

I saw a little smoke coming from the Audio Amp (LM3886t). That could be my fault from when I was probing and shorted a couple of leads on the amp!

I might be able to just replace the audio amp, but with all I've been reading on this site I'm thinking, hmm? What are my options with a different power supply PCB?


Closest service center is about 3hrs from here.

Thanks,

Bluesplay

[Enzo]

The power supply circuits look pretty conventional to me. Basic rectifiers, filter caps, and three-legged regulator ICs for the low voltage stuff. If the 3886 smoked, remove it, then power up the amp to see what further damage was done.

[bluesplay]

The power supply circuits look pretty conventional to me. Basic rectifiers, filter caps, and three-legged regulator ICs for the low voltage stuff. If the 3886 smoked, remove it, then power up the amp to see what further damage was done.

Ok. I'll give it a shot. Thanks.

Bluesplay

[bluesplay]

Holy cow! That was a lot of desoldering. Ok, so I removed the 3886 and commenced to see what else I might find that's bad and now I"m not getting any voltage on the secondary side of my transformer. The transformer should have two voltages
(10v and 56v). Can a transformer have intermitant probs,'cause at one time before I wasn't measuring voltage on the secondary side.

[Enzo]

Did you flip the meter back to AC volts? Stuck your probes into a wall outlet and see if 120VAC comes up.


It is extremely unlikely that both secomndaries have failed. If there truly is no AC coming from the secondaries, it is far more likely that the mains voltage is not making it to the primary.

[bluesplay]

Did you flip the meter back to AC volts? Stuck your probes into a wall outlet and see if 120VAC comes up.


It is extremely unlikely that both secomndaries have failed. If there truly is no AC coming from the secondaries, it is far more likely that the mains voltage is not making it to the primary.

Thanks Enzo. Thats really wierd, yes, I did flip back to AC and checked it at the primary and it shows 115v. Not sure where to go from here , your help is very much appreciated! .

[52 Bill]

...If there truly is no AC coming from the secondaries, it is far more likely that the mains voltage is not making it to the primary.

Internal thermal circuit breaker? Try reading the resistance of the primary winding.

[bluesplay]

Thats what I'm wondering, and how does it reset if thats the case. Meanwhile this eve I'll check the resistance on the windings.

[bluesplay]

Internal thermal circuit breaker? Try reading the resistance of the primary winding.

My transformer is definitely open, Checked the primary side and it is completely open.

transformer model number is ED14127R4
pri: 115 60hz 110W
Sec: 10V .25A
56V CT 1.4A

Any ideas of where to go to replace this or should I open it up and see if it has some type of thermal shut-off? I'm inclined to open it!