Tube Works BLUETUBE

[niftydog]

Just scored one for free from a work colleague (the old school pedal version that is). Low level in effect mode, that nasty brown goo all over the PCB... any advice or schematics? could it be the tube itself that's the problem?

This will be my first trip down the treacherous tube highway!

[Lonestarjohnny]

thats what I would replace first and also check the fuse in it, should have a fuse on the power supply if it run's off 117 v., if it runs off a wall wart it probably will not have a fuse. i have never seen a schematic on it.
LoneStarjohnny

[george]

if it run's off 117 v.

117V? that's for wimps.  Down under (like other outposts of the former British Empire) we run on a hairy chested 240V .... :-)

cheers

[niftydog]

we run on a hairy chested 240V

Yeah, but 20A will knock you on your arse faster than 10A!

[george]

lol! ... hope I never go there bro.

Sounds like changing the valve is a good first step.

I think Analog Mike has a schematic for the bluetube for $US5.

Apart from that you could look at the schematic for the 4-knob tube driver on GGG and compare it to what you can see on the PCB ... if you can see enough of the PCB I'd be looking for an op-amp as the other main gain-producing component (though as I recall the BT didn't have all that much gain ... makes me suspect that it's just a single valve stage with no op-amp in front

If all else fails build a Shaka Tube - they're nice!

[niftydog]

sweet, thanks george, I'll check out analog mike!

Just to keep you in the loop, guys. I've tried swapping out the tube for known goodies. No luck. There is a 4558 on the board, seems to be the bypass buffer, also seems to be working fine.

Bypass is fine, just the effect that's dead!

compare it to what you can see on the PCB

Unfortunately, it's largely a big lump of hard, shiny brown goo! Don't know if it's worth trying to dig it all off or not!


Worst case, I salvage what I can and use the box! It's got some nice knobs on it... and like you say, I've got a tube now, perhaps I can use it someplace!