mk iii boken capacitor

[sean]

i folks, thanks for this forum. however the reason why i found it is because my mk iii blue stripe (1990?) simul-class combo started smoking...i'm sure i need new tubes as it's been about 5 years since i replaced them. just to be sure it was nothing else, i opened my amp to take a look. i did find a broken brown-with-stripes capacitor connected to the tube socket. it's broken in half and has that "burned" smell. i just wanted to check with this forum to see if anyone may know why this happened and if it's relatively inexpensive to fix. i'm pretty nervous because i don't have a lot of time or money...i'm going to be touring in two days. thanks in advance!

 

[Boogiebabies]

That would probably be a 2 watt 470 ohm screen grid resistor. When tubes go down, they usually take that resistor with it. The amp can run without it, but it's best to have it fixed. It should take 5 minutes.

Where are you loacted. I keep vintage 470's and 1% metal oxide's on hand at all times. A few dozen at least.

 

[sean]

thanks a lot! i'm located in austin, texas. i see that there's a certified repair person down the street from me. i just hope it can be fixed quickly...

 

[Boogiebabies]

Anyone who works in vintage Fenders should have dozens in stock.
It's standard for the 6L6. If it's the EL34 sockets, a 1K 2 watt will work, but replace them on both EL34 sockets if they are not all 470 ohm anyway. Who knows what Mesa was using at the time.

Check to see if the first three on the resistor bands are all Yellow/Violet/Brown. The fourth is the tolerance.

 

[sean]

actually it is the el 34. it's colors look like red, violet, orange and silver from top to bottom. that is most certainly the problem. so i should get the pair replaced? thanks again!

 

[Boogiebabies]

Those colors do not add up. Worst case is they are 2.7K, but I would have them replaced.

 

[timv]

It is probably red violet red which would be 2.7K. That is what my mark 3 coliseum blue stripe has on the el34 sockets.

 

[triodal]

That would probably be a 2 watt 470 ohm screen grid resistor. When tubes go down, they usually take that resistor with it. The amp can run without it, but it's best to have it fixed. It should take 5 minutes.

Where are you loacted. I keep vintage 470's and 1% metal oxide's on hand at all times. A few dozen at least.

So everytime a power tubes go bad and fail,it will take the resistor also?

 

[jvk]

That would probably be a 2 watt 470 ohm screen grid resistor. When tubes go down, they usually take that resistor with it. The amp can run without it, but it's best to have it fixed. It should take 5 minutes.

Where are you loacted. I keep vintage 470's and 1% metal oxide's on hand at all times. A few dozen at least.

So everytime a power tubes go bad and fail,it will take the resistor also?

That happens often with Boogies.. other amps like ENGLs and H&Ks have a fuse sitting between the cathode and ground of each powertube.

Does the Road King have these fuses? I don't remember seeing them...