Smoke, and Sparks inside my Valve junior.

Low_fidelity2100

New member
Exactly as the title says.

There was smoke coming outta the back of my valve junior, and I saw a flashing behind it at the same time, The smoke smelled like Fireworks (if it matters). There was obviously some sparking/arching going on. But I dunno why. When the sparking and smoke happened, The amp also startted making popping noises and Humming very loudly. The Sparks/Flashes coincided with the popping noises.
I opened the chassis up after it happened, and Saw some scorch marks near one the chassis pins taht the circut board mounts onto. And when I removed the circut board, to check it for other obvious signs of "bad things" there was a tiny bit of scorching on there too (right near where the pin and board bolt together. Which is also where one of the circut traces taht connects to the output transformer is). So I put some electrical tape over both peices, and Fired it up again. And now everythings fine. I let it run for a bout 30 minutes without useing it to see if it would happen again, and It didn't. So It seems to be fixed Now. (but just cause it SEEMS that way, doesn't mean it is. ya know?)

But I can't figure out WHY it shorted/arced/sparked in the first place? I've never had a problem with it before. And Ireally can't figure out WHY I didn't get electricuted when it happened, seems like I should have been. And I really don't understand why none of the fuses blew when The short/arcing happened?
So I'm a little worried to use the amp now, considerign I really don't wanna get electricuted if it happens again.
So If anyone knows WHY this would have happened in the first place, how to avoid it happening in the future, Or whether the electrical tape will be sufficient to keep it from doing this again. Please let me know.

thanks in advance everyone.
 
Re: Smoke, and Sparks inside my Valve junior.

I've heard stuff about this before. It fries the tubes, man. I'm sure someone here will be able to help you with the technical stuff, and be able to give you a better explanation than I can. I hope you're able to get it fixed, man. Good luck.
 
Re: Smoke, and Sparks inside my Valve junior.

I've heard stuff about this before. It fries the tubes, man. I'm sure someone here will be able to help you with the technical stuff, and be able to give you a better explanation than I can. I hope you're able to get it fixed, man. Good luck.

Yeah, thats the thing.....the Tubes are Totally fine. Even when the sparking/flashin was goin on They were still glowing totally normally. I actually kinda though Perhaps one of them had shorted or sumthing, causeing the problem. But Nope theres absolutely Nothing wrong with them, nothing I can see anyways. Its weird.
 
Re: Smoke, and Sparks inside my Valve junior.

Yeah, thats the thing.....the Tubes are Totally fine. Even when the sparking/flashin was goin on They were still glowing totally normally. I actually kinda though Perhaps one of them had shorted or sumthing, causeing the problem. But Nope theres absolutely Nothing wrong with them, nothing I can see anyways. Its weird.

I read through as many reviews as I could find on those once when I was considering one, and I read a lot of similar things like what you're experiencing and everyone said the problem was that it was frying the tubes. I guess that's not really the problem after all.

I'm sure someone here would know what it is, though. People were raving about those things a while back and talking about all kinds of mods that can be done to 'em.
 
Re: Smoke, and Sparks inside my Valve junior.

That's weird. Usually, when you the let the smoke out, amps don't work any more.

It must still have some smoke left. ;)
 
Re: Smoke, and Sparks inside my Valve junior.

I'm not an amp tech, but I've seen things like that happen before. Basically, two metal parts situated too close to each other and the current is so strong it jumps across and burns a spot. You may have isolated it by putting the electrical tape there, but I'd still return it or have it fixed under warranty.
 
Re: Smoke, and Sparks inside my Valve junior.

I agree - you should take it to a tech and have it checked.

But this reminded me of an old story about one of the early computers. Same thing happened - and of course, the computers back then were all tubes as well - but that has nothing to do with it. Anyway, they went inside to see what was wrong and they found an insect fried across two leads. This was the first incident of a compter bug (true story).

Did you find any toasted moths anywhere in the room?
 
Re: Smoke, and Sparks inside my Valve junior.

I'm not an amp tech, but I've seen things like that happen before. Basically, two metal parts situated too close to each other and the current is so strong it jumps across and burns a spot. You may have isolated it by putting the electrical tape there, but I'd still return it or have it fixed under warranty.

Yeah, I'm pretty sure thats what happened. The Circut trace and the pin on the chassis were REALLY close together. I actually didn't Bolt the circut board Back onto that Pin, Just put a triple layer of electrical tape there. That pin really doesn't seem nessicarry anyways, Considering theres another pin/bolt about 1 inch away.

And I don't really think I can return it, Or have it fixed under warranty. I've had the amp for about 6 months, and as soon as I opened the chassis I voided the warranty (according to the paper work anyways). Plus I had modded it awhile back (the mod is in no way connected to the problem). I Did the mod to rectify the cathode heater current, which removes alot of the hum. So I'm pretty sure doing that Voided the warranty too. If I thought i was still covered by warranty, or I could return it, I would have done that, haha. But I'm fairly sure Its not.

So Should I be worried about getting electrocuted? Or ya think the electrical tape Thing would Be a suitable Fix? Cause I really don't have money to Take this into get it repaired. And Really Considering Its an amp that cost Me about $100, it would seem kinda dumb to pay even close to $100 to get it checked out/repaired. The amp seems totally fine now, so I dunno what to think really.
 
Re: Smoke, and Sparks inside my Valve junior.

I agree - you should take it to a tech and have it checked.

But this reminded me of an old story about one of the early computers. Same thing happened - and of course, the computers back then were all tubes as well - but that has nothing to do with it. Anyway, they went inside to see what was wrong and they found an insect fried across two leads. This was the first incident of a compter bug (true story).

Did you find any toasted moths anywhere in the room?

Haha, When I was talkin to my Dad about this amp stuff earlyer He Told me that SAME EXACT STORY! haha.

But anyways, he also gave me a similar theory as to what He thought might have happened in the amp....He said That since I have a Really hairy dog (and she's shedding right now), He thought Maybe some of my dogs hair had gotten inside there somehow. And Just happened to Bridge the gap between the chassis pin and the circut traces at the right moment, and That might have caused the short/aching to start. He also said that once the air gets Ionized because of the current, that even after the hair burns away, The ionized air will still carry the electical current until The power source is removed.
Thats what He thought anyways. Dunno if he's right, But it seems like a reasonable explaination. Although, that doesn't really mean its correct. Makes more sense than anything I've came up with on my own though (I assumed it was evil wood Gnomes or Pixies).
 
Re: Smoke, and Sparks inside my Valve junior.

If there's anyone in your area experienced with this type of work, it may be worth paying them for it. If the amps still works, I guess it's not a fuse problem, like I had about a year ago.
 
Re: Smoke, and Sparks inside my Valve junior.

'Ya get what 'ya pay for.

It's a $100 'toob' amp...

The "new" AC15 I played did the SAME THING but it didn't come back.

Heh, probably made in the same factory.



I'd have it checked out too...then launch it or keep it around for experiments...
 
Re: Smoke, and Sparks inside my Valve junior.

'Ya get what 'ya pay for.

It's a $100 'toob' amp...

The "new" AC15 I played did the SAME THING but it didn't come back.

Heh, probably made in the same factory.



I'd have it checked out too...then launch it or keep it around for experiments...


Yeah, I mean I'm not too concerned with it really. Like ya said, its a $100 tube amp, so I wasn't really expecting a "quality" constructed amp that would last a lifetime, or anything. haha.
I'm mainly Just a little confused as to Why I didn't get electrocuted. And Just kinda wonder what caused that all to happen.

I've played on the amp a little today with No problems at all. So I guess the tape thing worked, at least for now. But I'm still a bit concerned about getting zapped. Perhaps its time to do one of those mods to the bridge grounding on my guitars, so I won't get zapped as baddly if anything happens? Haha.

I also Talked to an amp tech today at the guitar shoppe I go to the most (guzzardo's in rockford IL). And explained the whole thing to him. And he was saying that Since where it happened was in such close proximity to the output tube, He thinks that Maybe the amp being on for awhile generated enough heat, To soften the solder on the connection that was the source of the arcing. So as soon as a little vibration happened, the Solder joint Coulda moved a tiny amount, Momentarily makeing contact with the Chassis Pin, Starting the electrical arc. He said The fact that The tube socket is Circut board mounted Makes this scenario even more likely. And I assume he knows what he's talkin about (if not someone should let me know though).

So I dunno, this is a bit confuseing to me. Like it seems to be fine now, But It seemed fine up until it started sparking and smoking before, So Who knows? haha.

Maybe this is a good excuse to build a champ clone, and just use the VJ's chassis/cabinet as a housing?
 
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