# Traynor YGL 3 FRIED heater wires!



## analogteletube (Jan 26, 2011)

So I finally got a chance to crank up my new to me YGL 3, and suddenly, crackle, poof, thick white smoke rising from the chassis. I immediately cut the power and unplugged it, took the top off and the filament wires above the power tubes (4xEL34) and all the way back to the phase inverter have the insulation burned completely off, and over the first power tube some of the wire itself is burnt right through. Has anyone ever experienced anything like this? Before re-wiring the filament supply are their any tests I could do to make sure the PT is ok?


----------



## nonreverb (Sep 19, 2006)

Wow! Sounds like the heater shorted with something it didn't like. Cut the burnt wires from the PI, pull the power tubes and fire it up in standby to see if the preamp tubes light up. 
I suspect one of your power tubes might be the culprit.
By the off chance, is it possible that one of the power tubes is inserted incorrectly? ie wrong pin locations.


----------



## analogteletube (Jan 26, 2011)

Hi nonreverb! thanks for the input! 

All the tubes were definitely in the correct orientation, all the notches aligned, I've used it quite a bit at lower volumes with no problems. I ended up just rewiring the filaments and putting some different tubes in, seems to be working fine again,,,...strange, i've been working on amps for a couple of years now and I've haven't seen or heard of anything like this ever happening... If it was a tube i have no way to tell which one, so now I have a quad of tubes, one of which might be and amp killer! Can a bad tube really short the whole filament chain like that? I guess I'll have to wait and see if the new wiring lasts!


----------



## nonreverb (Sep 19, 2006)

If the heater were to get shorted to the B+ somehow, the results could be spectacular...


----------



## GTmaker (Apr 24, 2006)

analogteletube said:


> So I finally got a chance to crank up my new to me YGL 3, and suddenly, crackle, poof, thick white smoke rising from the chassis. I immediately cut the power and unplugged it, took the top off and the filament wires above the power tubes (4xEL34) and all the way back to the phase inverter have the insulation burned completely off, and over the first power tube some of the wire itself is burnt right through. Has anyone ever experienced anything like this? Before re-wiring the filament supply are their any tests I could do to make sure the PT is ok?


All the smoke and burnt wires and you replace the tubes and wires and everything is OK....waoooo
I would want to know what caused all the fuss...
I know nothing about the inner workings of amps but I think this amp is trying to tell you something.
Actualy I think it shouted out loud "HEEEEEEELP ME!!!" ....but thats just what I think.

G.


----------



## nonreverb (Sep 19, 2006)

GTmaker said:


> All the smoke and burnt wires and you replace the tubes and wires and everything is OK....waoooo
> I would want to know what caused all the fuss...
> I know nothing about the inner workings of amps but I think this amp is trying to tell you something.
> Actualy I think it shouted out loud "HEEEEEEELP ME!!!" ....but thats just what I think.
> ...


A power tube shorted to the heater lines in the right(wrong) way or a short on one of the sockets could cause it. Lots of fireworks but not necessarily damaged permanently.


----------



## Wild Bill (May 3, 2006)

nonreverb said:


> A power tube shorted to the heater lines in the right(wrong) way or a short on one of the sockets could cause it. Lots of fireworks but not necessarily damaged permanently.


That's where a tube tester can quickly show if that's what happened. Lots of techs try to get by without one, by tube substitution, but sometimes we have questions like in this situation.

Me, I'm still wondering why the fuse didn't blow...

Wild Bill/Busen Amps


----------



## jb welder (Sep 14, 2010)

A heater to cathode short in a tube can do this, especially in power sections where the cathodes are grounded. Often the hum balance pot or resistors will be damaged when this happens. I don't think Traynor has any hum balance resistors or pot but most Fender's do.
Bill: I think the mains fuse did not blow because of the low voltage (6.3V). The wattage you would have to draw on the secondary side would have to be quite large to blow a fuse on the primary. I guess that's why some amps (some Marshall and others) have heater fuses aside from the mains fuse.


----------



## Wild Bill (May 3, 2006)

jb welder said:


> A heater to cathode short in a tube can do this, especially in power sections where the cathodes are grounded. Often the hum balance pot or resistors will be damaged when this happens. I don't think Traynor has any hum balance resistors or pot but most Fender's do.
> Bill: I think the mains fuse did not blow because of the low voltage (6.3V). The wattage you would have to draw on the secondary side would have to be quite large to blow a fuse on the primary. I guess that's why some amps (some Marshall and others) have heater fuses aside from the mains fuse.


Yeah, you'e right. This is a 100 watt amp, after all. That means a 5 amp fuse on the primary. Still, how many amps does it take to instantly fry filament wires? I suspect a heater to cathode short, which would have meant the filament winding would have seen a dead short. 'Course, slo-blo's were popular 'cuz of start up current. Which would blow first, the wire or the slo-blo fuse? LOL

It would be interesting to put those EL34's into a real tube tester.

Wild Bill/Busen Amps


----------



## dcole (Oct 8, 2008)

Hey Wild Bill,

While we are on the topic, what do you use for a tube tester? I personally use a Stark 9-66A.

I simple shorts tester can be built based of schematics of old tube testers or they can be found in old text books as well.

Thanks,

David Cole


----------



## jb welder (Sep 14, 2010)

analogteletube said:


> If it was a tube i have no way to tell which one, so now I have a quad of tubes, one of which might be and amp killer!


 You could measure the resistance with a meter, one probe to the cathode (pin 8), one probe to the heater (pin2 or 7). You may find a low resistance on one of the tubes, that would be the bad one. However, it could be that the fault only occurs with the tube in the amp and powered up. 
But you also mentioned one of the tubes had the wires burnt worse than the others. If you kept track of which tube that was, it is probably your bad one:


analogteletube said:


> over the first power tube some of the wire itself is burnt right through.


----------



## LydianGuitars (Apr 18, 2013)

nonreverb said:


> If the heater were to get shorted to the B+ somehow, the results could be spectacular...


Do you agree that a tube failure with an internal short could have caused this? That would be my guess.

I'm surprised that there's no heater strip fuse. I'm mostly a Marshall guy and most are pretty well protected in this area.


----------



## LydianGuitars (Apr 18, 2013)

dcole said:


> Hey Wild Bill,
> 
> While we are on the topic, what do you use for a tube tester? I personally use a Stark 9-66A.
> 
> ...


You can find shorts in a tube with just a digital multimeter. No need for a tube tester for that.


----------



## nonreverb (Sep 19, 2006)

LydianGuitars said:


> Do you agree that a tube failure with an internal short could have caused this? That would be my guess.
> 
> I'm surprised that there's no heater strip fuse. I'm mostly a Marshall guy and most are pretty well protected in this area.


Indeed, that would be my first guess. An H/C short, as earlier stated, causes the filament current to go extremely high. Fortunately, in this case, the wires burnt. However, I've seen this problem take out a power transformer too.
Hammond B3 power transformers use a 6X4 as a rectifier. When these go, there's no failsafe such as a fuse and it will take out the transformer on occasion if the short doesn't burn up in the tube.
It's nasty, smoky, smelly shit when that happens. I've resorted to subbing diodes, drop resistors and yes, fuses in my rentals now.....way too embarrassing when the organ goes up in smoke during a performance.


----------



## Wild Bill (May 3, 2006)

dcole said:


> Hey Wild Bill,
> 
> While we are on the topic, what do you use for a tube tester? I personally use a Stark 9-66A.
> 
> ...


I have about half a dozen testers lying around David but most of the time I use a very portable Sencor TC-162, which is a light and compact unit that at one time was popular for a tv repairman to take with him on house calls.

I also have a couple of the old tube caddy "briefcases" that the same repairman would bring in. One of them has a tube tester built inside! When you open it up the tester runs down the middle. That one needs some repair. I'll get a "roundtoit" someday!

A couple of months ago I got a REAL prize! A lady had gotten my number as someone who might be interested in something from her late father's estate. The man had been a TV repairman for years and she wanted this one piece to go to someone who would appreciate it. It is a genuine old-fashioned drug store tube tester! If you are old enough, you might remember how in the days of tubes if your TV stopped working your Dad would take out all the tubes and take them down to the local drug store or variety store, where they would have one of these testers. It sat on top of a tall cabinet with a locked door that held new tubes, with an advertising banner that was lit up on the top!

Since your dad likely wasn't a tech himself he would test ALL the tubes until he found the bad one! Then he would call over the clerk, who would unlock the cabinet and pull out a new tube for him. Dad would pay for it and then he would return home to put the tubes back in the TV, including the new one to replace the one that had failed. PRESTO! The family would again be watching The Ed Sullivan Show!

This unit is now a piece of display nostalgia furniture in my living room. It came full of NOS tubes, never used! Of course, most of them are no longer useful - who needs a high voltage rectifier tube for a 1959 Black and White television? Still, there are LOTS of tubes for the old radios I repair and collect and a surprising number of tubes used in guitar amps.

I consider myself very lucky to have acquired this piece. On EBay and Kijiji the smaller testers go anywhere from $25 to $100 tops but the big old drug store testers go for MUCH more! I saw one go for over $500 U$D a couple of years ago. They are extremely rare! I guess they didn't often survive after world went transistorized. Big items like this are hard to collect - they take up too much room! This is also why table top tube radios are very common but the big old entertainment units, particularly from the 40's and 50's, are rare indeed. I think I have only seen 2 on EBay in the last 5 years or more.

Of course, I have no intention of selling it myself! For a tube man, this is the ultimate in cool! I think I will end up bolting it directly into my living room floor, just to make sure it never leaves!kksjur

Wild Bill/Busen Amps


----------



## Lincoln (Jun 2, 2008)

Wild Bill, 
if you like old radios, here's something I picked up over the summer. Still plays too, but it's "stuck" on CBC.

View attachment 4553


View attachment 4554


I love these old things


----------



## dcole (Oct 8, 2008)

Sweet. I like that answer Wild Bill. Sounds like you could fill a few pages with nostalgia and what have you.


----------



## greco (Jul 15, 2007)

Lincoln said:


> Still plays too, but it's *"stuck" on CBC.*


A very intelligent old radio ...with class !

Cheers

Dave


----------



## Wild Bill (May 3, 2006)

greco said:


> A very intelligent old radio ...with class !
> 
> Cheers
> 
> Dave


Ditto, Dave! Lincoln has a pretty one there!

I have my differences with CBC TV political bias but I have aways been impressed with CBC Radio.

Wild Bill/Busen Amps


----------



## GTmaker (Apr 24, 2006)

analogteletube said:


> So I finally got a chance to crank up my new to me YGL 3, and *suddenly, crackle, poof, thick white smoke rising from the chassis.* I immediately cut the power and unplugged it, took the top off and the *filament wires above the power tubes (4xEL34) and all the way back to the phase inverter have the insulation burned completely off,* and over the* first power tube some of the wire itself is burnt right through*. Has anyone ever experienced anything like this? Before re-wiring the filament supply are their any tests I could do to make sure the PT is ok?


OK....I have come to the conlusion that all you amp teckies are insame and have obviously had way to much intake of whatever illegal powders/liquids are available.

Reason for my conclusion:
We have been told on an amp incident with words like
Smoke
insulation burned right off
wire itself is burnt right thru...

I'm thinking "wao ....this is serious and I know those teckies are gonna get to the bottom of this for the good of all of us."

What did I get ....a frikken ancient radio (obviuosly used by aliens) appreciation chat and a oh hum "just replace those chared wires and maybe a tube if you feel like it and it should be just fine."

you guys drive me crazy and thats all I have to say about that.

G.


----------



## nonreverb (Sep 19, 2006)

If you need knobs for that thing, I probably have 'em....



Lincoln said:


> Wild Bill,
> if you like old radios, here's something I picked up over the summer. Still plays too, but it's "stuck" on CBC.
> 
> View attachment 4553
> ...


----------



## Lincoln (Jun 2, 2008)

nonreverb said:


> If you need knobs for that thing, I probably have 'em....


Serious? That would be awesome. I looked up the model/serial number on the antique radio site, it's a 1946 or 47. I think that one remaining knob is original - it kinda matches the Phonola decal anyway.


----------



## nonreverb (Sep 19, 2006)

I think it's original as well. I'll look through my stuff 'n see what I can find...


----------



## dcole (Oct 8, 2008)

Sorry for that.



GTmaker said:


> OK....I have come to the conlusion that all you amp teckies are insame and have obviously had way to much intake of whatever illegal powders/liquids are available.
> 
> Reason for my conclusion:
> We have been told on an amp incident with words like
> ...


----------



## WCGill (Mar 27, 2009)

Good advice at a good rate, what's not to like?


----------



## analogteletube (Jan 26, 2011)

Great info ! I'll do that~ Thanks jb!


----------



## analogteletube (Jan 26, 2011)

Great info!, I'll do that!, thanks jb!


jb welder said:


> You could measure the resistance with a meter, one probe to the cathode (pin 8), one probe to the heater (pin2 or 7). You may find a low resistance on one of the tubes, that would be the bad one. However, it could be that the fault only occurs with the tube in the amp and powered up.
> But you also mentioned one of the tubes had the wires burnt worse than the others. If you kept track of which tube that was, it is probably your bad one:


----------



## analogteletube (Jan 26, 2011)

No big deal man! Its the natural flow of the thread! 


GTmaker said:


> OK....I have come to the conlusion that all you amp teckies are insame and have obviously had way to much intake of whatever illegal powders/liquids are available.
> 
> Reason for my conclusion:
> We have been told on an amp incident with words like
> ...


----------



## analogteletube (Jan 26, 2011)

Yes!, I wish i could afford a tube tester, not in my budget for a while!


Wild Bill said:


> That's where a tube tester can quickly show if that's what happened. Lots of techs try to get by without one, by tube substitution, but sometimes we have questions like in this situation.
> 
> Me, I'm still wondering why the fuse didn't blow...
> 
> Wild Bill/Busen Amps


----------



## analogteletube (Jan 26, 2011)

Just tried this with all the tubes, no luck unfortunately, thanks again though!


jb welder said:


> You could measure the resistance with a meter, one probe to the cathode (pin 8), one probe to the heater (pin2 or 7). You may find a low resistance on one of the tubes, that would be the bad one. However, it could be that the fault only occurs with the tube in the amp and powered up.
> But you also mentioned one of the tubes had the wires burnt worse than the others. If you kept track of which tube that was, it is probably your bad one:


----------



## analogteletube (Jan 26, 2011)

Agreed! +1


WCGill said:


> Good advice at a good rate, what's not to like?


----------



## nonreverb (Sep 19, 2006)

If the power tubes are old, I'd just replace them all. There's nothing worse than replacing one tube only to have another go shortly after. If they're new, the challenge is getting one tube that matches reasonably close. You don't want the replacement to be running too high a idle current compared to the others. It might not blow, but will wear faster than the others.



analogteletube said:


> Great info!, I'll do that!, thanks jb!


----------



## analogteletube (Jan 26, 2011)

So I should have a chance to crank the amp up again later on today, heaters are all rewired, solders double checked and new tubes, seems to be working fine in my apartment. I had used the amp for a month or two at low volumes with no problems, then the first time I cranked it up, pooF! So I'm anxious to see how it preforms this time! Thanks again to everyone who replied! 

P.S, Old radios and tube testers are rad!


----------



## Lincoln (Jun 2, 2008)

GTmaker said:


> OK....I have come to the conlusion that all you amp teckies are insame and have obviously had way to much intake of whatever illegal powders/liquids are available.
> 
> Reason for my conclusion:
> We have been told on an amp incident with words like
> ...


I'm to blame for the alien radio  But I'm sure you know that teckies dig old radios. Every teckie I know has a special place for them and as I recently found out, the teckies on GC do also. Old radios and other totally tubular devices are the "roots" from which the guitar amp evolved. 

As for the amp in question......it's just the heater curcuit, no big deal. 

Would it be cooler if that ancient alien cabinet was home to 5C5 pro chassis maybe?


----------



## nonreverb (Sep 19, 2006)

Just for the record...I inadvertently hit the dislike button on Lincoln's post which was of course, a mistake!!! Trigger happy clicker here not watching where he's got the mouse pointed....
If I could take it back, I would....



Lincoln said:


> I'm to blame for the alien radio  But I'm sure you know that teckies dig old radios. Every teckie I know has a special place for them and as I recently found out, the teckies on GC do also. Old radios and other totally tubular devices are the "roots" from which the guitar amp evolved.
> 
> As for the amp in question......it's just the heater curcuit, no big deal.
> 
> Would it be cooler if that ancient alien cabinet was home to 5C5 pro chassis maybe?


----------



## analogteletube (Jan 26, 2011)

Incase anyone is wondering the I've had a few chances to crank it up and the ygl3 is working great, thanks to everyone for your input!


----------

