OOps.. can it be fixed?

[bearhart74]

Older, non DI, EBS valve drives don't like it when you plug 12vdc into the 12vac power plug.
Any idea of it repairable or do I just keep it as a momento of a bad mistake?
No smoke, no weird noises but just stopped working (no surprize there).

 

[bearhart74]

Buehler?

 

[ctmullins]

Maybe try the Effects forum?

 

[stigbeve]

Hopefully just a fuse. May have to use a soldering iron. Hopefully someone with more knowledge will chime in.

 

[Crater]

I saw a schematic of the valve drive, it has a fuse on the 12 VAC power input, the parts list calls it a "microfuse" so I think it's the type that's soldered to the board. Funny thing though, the board layout that comes with the schematic doesn't show the fuse location on top of the PC board. Follow the traces from the power jack - one trace goes to the fuse. the other trace goes to the step-up transformer and the rectifier for the tube heaters.

 

[fig]

Funny thing though, the board layout that comes with the schematic doesn't show the fuse location on top of the PC board.

I had some time to waste and went looking for pics of the EBS Valve Drive. I'm not familiar with it and don't know of model changes thru the years, so this model may not be the right one. But I found some pics that someone took in this forum: Invalid Link Removed

Here's one pic I lightened and sharpened for clarity. Seems to be the solder-in type fuse on the back of the largest of the three boards. The printing is upside down, but looks like FUSE/1A. Not too clear, though. Needs visual to verify amperage rating.:

Hope that helps, @bearhart74. Like others have mentioned, that'd be the first place I'd check. And if this is the wrong model, ...well... I'm gonna blame it on my dog LOL.

 

[deepestend]

Could also be a blown zener diode... which is often also used for voltage protection. Look for one of these guys and see if it's a little burnt: https://qph.fs.quoracdn.net/main-qimg-f51a41a0c5312996ed0a94374cf58ada

 

[fig]

Uploading a pdf in here is kicking my butt...

So, in the link I posted earlier, here's page 2...
Invalid Link Removed

...scroll down about 3/4 of page, look for an attachment with a pdf link by "chicago-mike", 22 Nov 2012, 07:12. It's an original EBS document for the non-DI ValveDrive that contains a components list, component placement diagram, full schematic.

@Crater, is this the info you saw?

Anyway, @bearhart74, hope this helps. If you don't fix it yourself, your friendly neighborhood tech would probably appreciate this info.

 

[Crater]

@Crater, is this the info you saw?

Yes.