| Author |
Topic: Could it be just heat? Twin blew a fuse |
Lane Gray
From:
Topeka, KS
|
Posted 27 Jan 2013 8:20 pm |
|
My twin just blew a fuse. I wasn't pushing it real hard, but somebody had pushed it against a seat, so it couldn't breath. It was really hot, though. I'll get another fuse in the morning. I guess I'm wondering whether something else caused it or if poor ventilation can do it.
Not in the mood for a repair bill
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
|
|
 |
Stephen Cowell
From:
Round Rock, Texas, USA
|
Posted 27 Jan 2013 8:52 pm
|
|
It might have got hot enough for one or more of the finals to 'cherry up'... when they get real hot, the cathode starts to go into extra emission, causing more bias current to flow.
Is your fuse of the correct rating and type? Might be time for a bench check by your friendly amp mechanic... if your tubes got that hot your matching and bias needs to be checked again.
_________________
Too much junk to list... always getting more. |
|
|
|
Kyle Everson
From:
Nashville, Tennessee
|
Posted 27 Jan 2013 9:48 pm
|
|
| I've had that happen with twins in downtown Nashville a good bit. bad power is a common cause. if everything checks out ok with your tech, a good defense is a variac, which allows you to regulate the voltage your amp sees. power here can vary from 70-80 to 130-140 volts! your fender prob wants to see 120 average. |
|
|
|
Keith Hilton
From:
248 Laurel Road Ozark, Missouri 65721
|
Posted 28 Jan 2013 2:14 pm
|
|
| What is the proper amp rating of the fuse? |
|
|
|
Lane Gray
From:
Topeka, KS
|
Posted 28 Jan 2013 2:40 pm
|
|
4A Slow blow. I am NOT near the amp at the moment, and it was dark last night, so I am merely assuming it had the right value.
EDIT: When I assume something, I make an assu me.
It only had a 3A Slo-Blo
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
|
|
|
Keith Hilton
From:
248 Laurel Road Ozark, Missouri 65721
|
Posted 28 Jan 2013 9:10 pm
|
|
| I think that is what my 100 watt Fender Vibro Sonic has, 3 amp. I had the same problems you are having Lane. Nothing was wrong with the amp. I personally think it was a power supply problem in a couple of places I was playing. It has not happened since those two times the fuse went, and all I did was replace the fuse. |
|
|
|
Lane Gray
From:
Topeka, KS
|
Posted 4 Feb 2013 11:04 am
|
|
Put new fuse in it. Now it's humming even without a guitar plugged into it. I am wondering if I should take it to the shop, or just teach it the words
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects
Last edited by Lane Gray on 4 Feb 2013 9:36 pm; edited 2 times in total |
|
|
|
Stephen Cowell
From:
Round Rock, Texas, USA
|
Posted 4 Feb 2013 12:49 pm
|
|
| Lane Gray wrote: |
| Put new fuse in it. Now it's humming even without a guitar plug into it. I am wondering if I should take it to the shop, or just teach it the words |
Yes... it might have shorted (then blown out) a final tube... in which case you're firing on 3 cylinders. Or it might have popped a filter cap... either way, it's telling you (humming to you) the 'take me to a tech' tune.
_________________
Too much junk to list... always getting more. |
|
|
|
Lane Gray
From:
Topeka, KS
|
Posted 4 Feb 2013 1:20 pm
|
|
No distortion when it plays Tele or steel. I forgot to mention that part, but yes, it is on the way to the tech
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
|
|
|
Bill A. Moore
From:
Silver City, New Mexico, USA
|
Posted 4 Feb 2013 2:44 pm
|
|
Years ago we were out in the sticks playing a gig when the Bassman started distorting, and I could see one of the power tubes flashing blue in time with the distortion. I took 2 tubes from the Twin, and replaced the flashing one in the Bassman, and we got through the night. After, I pulled the tube from the bass amp to put the Twin back together, but the guitar player wouldn't let me, said his amp never sounded so good.
I don't think he ever played with all 4 tubes again! |
|
|
|
Lane Gray
From:
Topeka, KS
|
Posted 4 Feb 2013 2:47 pm
|
|
You called it, Mr. Cowell. V10 shorted out a grid screen, taking out the fuse. A new set of Groove tubes is on order.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
|
|
|
David Mason
From:
Cambridge, MD, USA
|
Posted 4 Feb 2013 6:19 pm
|
|
| You know, in the past few years, they've started making these things called "transistor" or "solid-state" amps, you might wanna look into that. When they short out they don't just blow a fuse, they usually burn the place down, which would serve the cheapskate right for providing substandard power in the first place. The nerve of these people. |
|
|
|
Lane Gray
From:
Topeka, KS
|
Posted 4 Feb 2013 6:26 pm
|
|
I got 3 of them newfangled Trans sister amps.
The Evans 500, PeeVee LTD and Session 500.
And the Twin sounds better than them.
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
|
|
|
Darrel Roberts
From:
Alabama, USA
|
Posted 4 Feb 2013 8:13 pm Twin
|
|
| Lane Gray wrote: |
I got 3 of them newfangled Trans sister amps.
The Evans 500, PeeVee LTD and Session 500.
And the Twin sounds better than them. |
Copy that on the Twin, Lane. Got a Vibrosonic and a boutique SS. Vibro gets the nod every time. Love them tubers. |
|
|
|
Chris LeDrew
From:
Canada
|
Posted 4 Feb 2013 8:27 pm
|
|
Have you got a reissue or a hand-wired original? The reissues are notorious fuse-blowers. I returned two Custom 15's for this reason.
_________________
Jackson Steel Guitars
Web: www.chrisledrew.com |
|
|
|
Lane Gray
From:
Topeka, KS
|
Posted 4 Feb 2013 8:55 pm
|
|
Reissue. My amp tech offers rewire to point to point boards. If it happens again, I may do that.
But it appears the tube went first
_________________
2 pedal steels, a lapStrat, and an 8-string Dobro (and 3 ukes)
More amps than guitars, and not many effects |
|
|
|
Jeff Scott Brown
From:
O'Fallon Missouri, USA
|
Posted 4 Feb 2013 9:04 pm
|
|
| Lane Gray wrote: |
| Put new fuse in it. Now it's humming even without a guitar plug into it. I am wondering if I should take it to the shop, or just teach it the words |
I get it. Funny. 
JSB
_________________
GFI Ultra S10 Keyless
Peavey Nashville 112
Goodrich L120, BJS, Peterson StroboPlus HD |
|
|
|
Dan Beller-McKenna
From:
Durham, New Hampshire, USA
|
Posted 5 Feb 2013 3:05 am
|
|
| I had a RI twin which went stone cold dead on me one day without any warning. took it to the tech who informed me that it has an internal fuse as well that sits on the PC board. How annoying! |
|
|
|
Stephen Cowell
From:
Round Rock, Texas, USA
|
Posted 5 Feb 2013 8:52 pm
|
|
| Dan Beller-McKenna wrote: |
| I had a RI twin which went stone cold dead on me one day without any warning. took it to the tech who informed me that it has an internal fuse as well that sits on the PC board. How annoying! |
The internal HT fuse protects the transformers... much better to replace the fuse than one of the transformers! I had a Peavey Classic 20 that had a thermal fuse inside the power transformer... let it get too hot and too bad, time for a new transformer... unless you're an adventurous sort, like me... locate it and bypass it! Sell the amp soon, though.
I have an Orange Tiny Terror (not good for steel!)... it has the high-voltage fuse available on the back, and the normal fuse is internal... opposite of your situation. Any amp using EL84's should probably do this, since they do tend to go *zorch* after about 2 years of use, taking out the HT fuse.
_________________
Too much junk to list... always getting more. |
|
|
|
Bill Howard
From:
Indiana, USA
|
Posted 14 Feb 2013 12:09 pm Caps??
|
|
| I had a friend who had a twin kept blowing fuses and getting hot, He took it to tech who put new caps in fixed it,,, |
|
|
|
Howard Montgomery
From:
Topeka, KS US
|
Posted 14 Feb 2013 3:14 pm
|
|
| The internal fuse on the Twin Reissue is for the heaters circuit. Thinking of relocating mine to the back panel just in case. It is a 10A slow blow fuse. I don't know when they added it, as I don't see it on older schematics or layout drawings. |
|
|
|
Larry Bressington
From:
Nebraska
|
Posted 14 Feb 2013 4:57 pm
|
|
A capacitor might have come loose from it's connection, seen solder melt before on Valve amps. Also seen melted Power transformer wire shorted due to heat and age.
_________________
A.K.A Chappy. |
|
|
|
