Bugera 6262 Warms up, Chatters, Channel LEDs Blink, Current Limiter turns into the Sun...?

[Just Mike]

Or starts to. I then switch it into standby to avoid a supernova. Before all this, the amp passes signal and all 3 channels work. I'm guessing this is a symptom of a bad connector or solder joint but on a precursory exam of the main(?) board I don't see anything obvious. It's not relay chatter I'm talking about, more like a sputtering sound coming from the speaker. Is there a schematic available?

[g1]

Any big signal is going to make the bulb light up, whether it's a good signal, or crackle, noise, etc. Was the amp blowing fuse or some other fault? What was the cause of you putting it on the lamp limiter?

[vintagekiki]

Is there a schematic available?

http://bee.mif.pg.gda.pl/ciasteczkowypotwor/%23SM_scena/Bugera/

https://pdfslide.net/documents/6262-rev-f-schematic.html

https://music-electronics-forum.com/forum/schematic-requests/42338-links-to-bugera-schematics?t=41278

1)
Bugera 333XL, 6262, V55
#6

https://music-electronics-forum.com/forum/amplification/guitar-amps/maintenance-troubleshooting-repair/42638-bugera-6262-infinium-head-problem-no-amplified-sound

2)
https://www.marshallforum.com/threads/troubleshooting-a-bugera-6262-5150-6505-clone.98681/

[Just Mike]

Any big signal is going to make the bulb light up, whether it's a good signal, or crackle, noise, etc. Was the amp blowing fuse or some other fault? What was the cause of you putting it on the lamp limiter?

The owner said it blew fuses. But it came in with a shattered preamp tube. I don't know what caused what. I just do it as a precaution when I fire up a new patient.

[g1]

Bad sounds and fuse blowing, I would first try other power tubes.

[The Dude]

Is the "sputtering sound" with signal applied to the amp or none? If you are running the amp on the limiter, it could simply be that supplies are dropping because of the LBL. The LBL is meant for initial testing. The amp is not meant to be run on the limiter.

[nickb]

Bad sounds and fuse blowing, I would first try other power tubes.

That was my first thought too. But then there's the channel LEDS blinking so now I'm thinking a power supply issue. These use lots of connectors and they are often a source of trouble. Have a thorough check for loose, burnt or tarnished pins on any power related ones.

[g1]

That was my first thought too. But then there's the channel LEDS blinking so now I'm thinking a power supply issue.

Agree but the limiter lamp might create supply glitches as well? I don't think it's been run off the bulb.

Maybe he could pull the power tubes and try it off the bulb.

[Just Mike]

Removed the limiter and plugged straight in. No blinks and it seems to be working properly now. I'm keeping an eye on it, but it looks like it just had a bad tube.