[xaro]

This morning I turned on my headphone amp and noticed I wasn’t getting any sound. After checking out everything I noticed a a familiar electronic burning smell and saw that one of the longer tubes in the middle had a black hue to it. After taking off the bottom panel I saw that the base where the tube plugs in is slightly discolored near one of the holes.Is this amp gone? Or is it salvageable?

 

[xaro]

Anyone?

 

[telecaster]

Take it to the vet and dont touch anything inside if you don't know tube amp. You can die or get seriously hurt even when disconnecting the plug.
Yes it can be restored, the vet will check it.
It is not a PCB cheap electronic that you cannot repair unless changing the PCB. It is a point to point wiring design, so a good tech can unsolder and resolder!

 

[john57]

The reason that you can get hurt inside the tube amp is that those big caps can store very high voltages for days at a time unless the design uses bleeder resistors otherwise you can have a serious injury. Already send you a PM

 

[xaro]

After some troubleshooting with someone on the fourms we've found out that one of the 2 now white resistors are bad



This was the only info i could find on them

RX21-10W
Resange 0.15 ohm~22k ohm
Resistance tolerance: +/-5%, +/-10%
Size: 9.5 x 37.5mm
Terminal size l: 30+/-2mm, diameter: d: 1.1mm


Anyone know where a good place to buy a replacement?

 

[john57]

The resistors in question that are highlighted in you report are sand or cement block that has a resistance value of 33k ohms and at least 10w watts of power capability. You can goggle it and usually the metal type is a bit more common is this power range but would required it to be screw in. Just make sure you get the resistor at least 10w or more. However I find this part confusing
 
Resange 0.15 ohm~22k ohm
 

 

[john57]

Looking at this again I wonder if the resistors are used as bleeders meaning to drain off the high voltage when the amp is turn off. This will prevent you from getting a shock when working inside the amp even when the power plug is pulled. You could have a bad capacitor that caused the bleeders resistor to blow but the resistor is not needed during the amp operation. I noticed but not as clearly the middle black capacitor looks like something may be leaking on the top. If that is the case the bad cap might be the root cause.  

 

[xaro]

On the center cap the black film that they put over it that shows the cap rating has peeled off a little and you can see the metal casing.
Those are the voltages i got when taking a multimeter up to it
 

 

[john57]

I can not tell from the picture if any of two white resistors are connected to ground. If the end with end with no voltage is connected to ground they you should not have a reading. But if that not the cause and yes you should have a reading. I can not tell from the picture which tabs on the caps and the resistors are  connected to the top or bottom buss wire.

 

[xaro]

The cap and resistor that have no voltage has a metal rod leading from them down to the cap that i've marked red.


This second pic is the side with power and it looks like its grounded to a little black box thats bolted to the side of the frame
 

 

[xaro]

http://www.cablesandconnectors.com/PIX/nte10r.jpg
33-Ohm 10 Watt Power Wirewound Resistor (2pk )

Would that resistor work as a replacement?