Bare Knuckle Pickups Forum
Forum Ringside => Tech => Topic started by: Elliot on June 06, 2010, 09:15:43 PM
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Switched on my Blues Junior tonight only to notice that I put a power tube in the wrong way round (a stupid error, a its too hot and I am tired type error). Any way the amp made a grating sound and a smoke plume came out the - There is a massive black scorch mark in the PCB and three of the big resistors have clearly burnt out. Its a nice amp in terms of tone - but B Jr's have notoriously cheap PCB's - is this kind of damage repairable?
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A lot will depend on how much colateral damage has been done.
You can repair PCBs as long as you can get any carbon deposits away from any potential short circuits.
A photo would be most helpful.
The only other alternative would be to replace the PCB, although my expereinec of extracting spares from Fender this could take a while.......
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Cheers,
Here is a picture
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Nice.
Looks like you've followed the old adage: "Tune for maximum smoke, then change the black parts." :)
Should be repairable. Did a fuse not blow?
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Unfortunately not - I was only on for a few seconds when I realised that I had forgotten to be careful to slot the tube in with the broken notch by matching where the notch once was with its hole.
Any one good in London for this type of repair?
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Unfortunately not - I was only on for a few seconds when I realised that I had forgotten to be careful to slot the tube in with the broken notch by matching where the notch once was with its hole.
Any one good in London for this type of repair?
JPF's yer man. :wink:
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as Martin said, JPF is the go-to guy in London.
it may well be worth while considering a PTP rewire of the amp while its getting sorted - there are plenty of places on the net that do drop-in turret boards for these amps, or Frank will be able to make a suitable one I'm sure.
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Just a word about pulling tubes from old amps - if there's a chance that the locator pin is broken then it's a good idea to draw a line on the valve base and the socket before you pull the tube out so you know it'll go back in the right way round. I usually number the tubes too, just so I know they're going back in the same sockets.
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Just to say Frank at JPF has done a sterling and very speedy job in repairing the Blues Junior - so it is rocking again as if the fire never happened.
Cheers Frank :D