Peavey Ultra 112 Tube Combo

[chikqo]

Hi everyone...
I'm new entering to this forum... this is my first time posting a threat and I hope you guys could help me. I'm not a tech but I'm fascinated with this kind of repairs and electronic stuffs so I'm a rookie.

Yesterday a friend offered to me a Peavey Ultra 112 Tube Combo for $80 he told the only thing it needs is a pair of tubes, I took it to my home and tried a pair of fender 6l6gc that I have left and that I checked on the web were the ones tha amp use. But when I switched it on, the leds never turned on though the tubes were on and looking normal, then I continued for a while verifying by the little knowledge I have what could be happening and when I checked again the tubes were illuminating too much, like regular light bulbs, and then quickly I turned it off trying to avoid that the tubes go damaged. After that I opened the amp and looking, I noticed that one of the fuses were fused. Could this be the problem? I tried to get new fuses but the amplifier need 5 and when I was checking they are supposed to be 250v and every fuse says 250v but the amp# was different in each one and I don't know if that's O.K. It seems like someone put the first fuses that found without take care of the right specs. If someone could tell me what's the specific fuse I need for this amp, I'll appreciate it. Sorry for all the talking but I like to be the most explained possible and as I can be. Thank you for your help.

[Amp Kat]

On the fuse itself maybe the opposite side of the 250 volts should be an amperage rating. If it's a ceramic white one it is most likely 10 amps. You need to find which part of the circuit the fuse blew. I think there are about 3 fuses inside the amp and one external. The external should be about 2 to 3 amps. On the inside are 3 I think. One for high voltage about 500ma's 1 for the heaters which is most likely a 10 amp and a bias fuse which may be an amp max. Do you know which one it is ? It also sounds like you have the tubes in backwards so check that out too.

[Enzo]

Yes, if your LEDs don't come on, you have a blown fuse. Probably the ones they took out before you got the amp were bad. BAd tubes are THE main reason for blown fuses in tube amps.

PLease be careful, the voltages these amps run on can KILL YOU.

It is normal to have different value fuses in the different clips, after all each fuse does a different job. I hope you kept track if whuch value went where.

The two fuses closer to the front - closest to the LEDs - are both 1 amp normal blow fuses. The one in the rear corner I think is the ceramic one. It should be 8 amps. The other one left is also 1 amp - it is hte high voltage fuse. The main fuse is not on the circuit board. If it was blown, the amp woul dbe completely dead. If ANYTHING on the amp comes to life, then the main fuse is OK.

Of course with a new fuse in place, we might find there is further trouble in the amp.

[chikqo]

Peavey Ultra 112 tube combo

Thank You Enzo & Amp Kat
I'm taking notes, your info is very valuable... so you're the best. I remember the place where the blown fuse and the ceramic fuse were but the others I'll figure it out by the info that you gave me here. I'll check this again to see if I certainly got it and will replying later. The ceramic one the amperage rating I could read was 10. By the way I saw in one of the other threats that somebody has the schematic of this amp and if it is not annoyance and this person is one of you guys I'll appreciate a lot if you can share it with me. Thanks again.

[Amp Kat]

If you email the cutomer service dept. at Peavey they will most likely email you a schematic in pdf form in a matter of minutes. Of course that is domestic so be a tad more patient for international but still should be somewhat quick as their customer service is one of the best in the world if not the best.