single wrecked

[flintstoned]

What do I do with this?

I started to get motorboating in the effects loop with certain effects and also noticed one tube started having a wicked blue glow to it, after trying a new set of tubes with no improvement, I started searching the net and found this bad ass forum. So i decided to oped her up and found this damage. So I thought no problem, i'll just hardwire point to point any traces that were lost and replace the resistors, but the resistors meter out okay and traces show continuity, so now what? I emailed mesa about a replacement so im waiting on that but if I band aid this back together will there be any improvement?

 

[flintstoned]

Shoot, my pics didn't upload, anyways my board that has the power tubes on it is burned up a lil bit. Ill try to get the pics up, tinypic doesn't work here? Who do you guys use here?

 

[jpdennis]

... tinypic doesn't work here? Who do you guys use here? ...

Photobucket.

Dennis

 

[flintstoned]

Second attempt:


http://m1070.photobucket.com/albumview/albums/flintstoned1/2012-07-18_18-56-16_858.jpg.html?o=0

 

[jpdennis]

Second attempt:


http://m1070.photobucket.com/albumview/albums/flintstoned1/2012-07-18_18-56-16_858.jpg.html?o=0

Use the link copy feature in Photobucket

Dennis

 

[flintstoned]

 

[msi]

You could call Mesa and e-mail your pictures. They may be willing to sell you the whole board populated as it is a pretty unremarkable part of the amp. There are no trade secrets or anything worth copying on that board.

 

[flintstoned]

Well mesa replied to my email and didn't say anything about selling me a replacement, just advised me to clean up the board and repair it, which I did and it seems okay so far. But as far as the motarboating in the effects loop, I tried a few different 12ax7's in v4 and still had the same problem. I haven't been able to find a good schematic yet so I can start taking some measurements with the meter but I don't see anything obvious like burnt resistors or swollen caps anywhere.

 

[Monsta-Tone]

My Rectoverb board has the same problem. I cleaned it up a little and bypassed one solder tab that was shot. So far, so good!

As for the loop, what are you running in it?
The loop on your amp is parallel (has a Mix pot).
You will most likely want to change it to Series.

I run a G-Major 2 through mine with no problems at all, now that it's wired in series.
Do a search on the forum. You should have no problem finding tons of info on it.
I have a drawing that I can email you, but it's for a DC-5, so the wire colors may not be correct for your amp. The wiring layout should be the same though.

andy at amps - tubes dot com

The Send jack on your amp will pass all of the signal through it after the series mod. You may have to use a short patch cable between Send & Return if the loop is not in use.

 

[flintstoned]

Thanks andy! I have seen that series mod in threads here when I was searching on this issue. Im running tc toneprints thru the loop. I thought it was odd that the reverb and delay worked fine but the chorus was the problem. So does this mean its a phasing issue with the parallel loop?