Technical Amp Question! (need help!)

[Eblis]

Hello everyone! I have a Peavey Heritage amp that was sitting in a garage for a while. On the day I got it I fired it up and it sounded ok. One speaker had a hole in it but it was fine otherwise. (keeping in mind the screwed up speaker). The power was ok and all the knobs functioned well. Now... I took the speakers out to repair them and to clean the mold out of the inside of the cabinet. I didnt touch anything else in there and i didnt get anything in there wet while cleaning.

The problem:

Today i tried it out again and it seems to have no power. There is a faint sound (of the guitar) comming from the speakers when I play but it has no volume and it seems like nothing is working. The tubes do not get hot. Should they? Ive never owned a tube amp before.

Basically my question is: Do any of you experts have any clue to what might be the problem?

Thanks,
Jason :smack:

(sorry this is a long post but i tried to present as much of the problem to help with diagnosis)

 

[Young Angus]

Re: Technical Amp Question! (need help!)

I dont really know what that could be, but just had to say thats not a very long post dude, its okay

 

[Gearjoneser]

Re: Technical Amp Question! (need help!)

Check the fuse first. It's the screw cap on the back of the chassis. Maybe the speaker is shorted out? Maybe a preamp tube is dead? If you were cleaning it, it's possible that your hand bumped a tube and it died, or is loose enough to kill it's connection. Unplug the amp, and pull out the tubes, and push them back in. Unhook the speaker and hook it back up.

 

[kmcguitars]

Re: Technical Amp Question! (need help!)

This is more a Question for Jeff Seal or Kent etc.. But untill they chime in I'll
give you a bump and opinion. Sounds like a power supply problem.

 

[Teleplayer1]

Re: Technical Amp Question! (need help!)

I have a Peavey Special 130 and you have to plug the reverb/channel switch in or you get no sound to speak of.

 

[Jeff Seal]

Re: Technical Amp Question! (need help!)

The Heritage's are pretty solidly built, but they have some "quirks" about them...(no more than most Peavey's of this era...)

If the tubes are glowing.....(they have heaters in them that glow "orange" when they're on)....then you're good there...try both high and low settings on the standby switch.....

With the amp off, unplug the speaker jack from the Main spkr jack and plug it into the Aux spkr jack right next to it... Turn amp back on, if the amp suddenly starts working...it's an indication the "switch" part of this jack is just corroded and needs to be cleaned .......cleaning it is as simple as just plugging/unplugging the spkr cord about twenty times from the aux jack...(what you're doing is cleaning the metal to metal contacts that are built into the jack...there's one contact that's made when something's plugged in and another one when nothing's plugged in...this one feeds the main spkr jack...)

If this didn't fix it, unplug your guitar from the front of the amp and plug it into the "pwr amp" jack right next to the footswitch jack and see if you get sound....if you do, then plug and unplug the cable into this jack about twenty times...

....let us know.....

Jeff Seal

 

[Scott_F]

Re: Technical Amp Question! (need help!)

Short in the speaker jack if you ask me.

 

[knucklefux]

Re: Technical Amp Question! (need help!)

maybe the speakers are out of phase. if this amp has a push-pull power section, it'll fry the output transformer if you connect the speakers wrong.

 

[Jeff Seal]

Re: Technical Amp Question! (need help!)

maybe the speakers are out of phase. if this amp has a push-pull power section, it'll fry the output transformer if you connect the speakers wrong.

..... ehhhh, I mean absolutely no disrepect, but that is 100% inaccurate....the secondary side of the output transformer will not be affected by how it's load is "phased".....

again, no offense meant, but I believe you may have gotten some bad info somewhere......

Jeff Seal

 

[Eblis]

Re: Technical Amp Question! (need help!)

Hello again everyone!

Update:

I took the amp apart and one of the fuses were blown. I replaced it it works fine now! I didnt know that there were 3 other fuses up in the control area of the amp.

Thanks to everyone who replied with suggestions!

Jason

 

[kmcguitars]

Re: Technical Amp Question! (need help!)

Hello again everyone!

Update:

I took the amp apart and one of the fuses were blown. I replaced it it works fine now! I didnt know that there were 3 other fuses up in the control area of the amp.

Thanks to everyone who replied with suggestions!

Jason

AH HA !! I was going to mention to you, if it's like my VTX there is 3 fuses
on the power supply board. But there real close to the filter caps And I
didn't think it was a good idea for me to sugest you go poking around in
there. Glad you got it working.
I was thinking it may be a good idea for someone(More Quilfied than me)
to write a Filter cap safety 101, And put it in the Vault. This way our
fellow forum brothers Will be aware of the DANGER!! :saeek: lurking inside
a Amp. I'd hate to get someone electricuted poking around in a Amp without
this knowledge. This way anytime a thread like this pops up we could link it
the safety thread. It would be wise to discourage most from going inside a
amp. But if they are gonna do it anyway? They might aswell be Imformed
of the leathal voltage they might discover the hard way !! :smack:
BETTER ONE OF US TELL THEM THAN ST. PETER :newangel:

 

[Eblis]

Re: Technical Amp Question! (need help!)

KC, it is a VTX. So what you are saying is that even though the amp is unplugged and OFF its possible to still get a shock if you touch the wrong thing?

Id like a little insight on this if possible.

I'm glad i was careful.

Jason. :saeek:

 

[kmcguitars]

Re: Technical Amp Question! (need help!)

KC, it is a VTX. So what you are saying is that even though the amp is unplugged and OFF its possible to still get a shock if you touch the wrong thing?

Id like a little insight on this if possible.

I'm glad i was careful.

Jason. :saeek:

YES !! right by the fuses you pulled. You may have noticed a few large
Grey cylindric Capasitors. Those are Electrolytic caps. They store
voltage inside EVEN WITH THE AMP OFF!! anytime you work inside a
amp these shoud be dischared. I'm NOT A AMP TECH so I'm not the
most Quilfied person to explain how to discharge caps. I could tell you
how i do it. But I think it's best explained by a Tech.

 

[kmcguitars]

Re: Technical Amp Question! (need help!)

YES !! right by the fuses you pulled. You may have noticed a few large
Grey cylindric Capasitors. Those are Electrolytic caps. They store
voltage inside EVEN WITH THE AMP OFF!! anytime you work inside a
amp these shoud be dischared. I'm NOT A AMP TECH so I'm not the
most Quilfied person to explain how to discharge caps. I could tell you
how i do it. But I think it's best explained by a Tech.

https://forum.seymourduncan.com/showthread.php?t=15508&highlight=filter+cap+safety
O.K. Here it is Explained by a Tech. Maybe vault matrial?

 

[Eblis]

Re: Technical Amp Question! (need help!)

Thanks for the info. I wont be messing around in there anymore.