Blues Jr tube board..just ordered mine..

[73fender]

Hello, originally posted this on the fb page, Doug recommended I come here. Turned out I joined in the past at some point. Anyway:

I have a cream board Blues Jr that, over the years, I have done most of Bill M's mods to. Lately I have been having issues with the tube pcb..the power tube socket connections I believe..sound cuts out, returns if I wiggle the power tubes (tried other tubes too). Reflowed the solder on the pin connections..worked for a while but problem returned. Was getting ready to muddle through figuring out how to run straight wires when someone on the Tele forum told me Hoffman amps has a kit..had a look and it appears to be just what the doctor ordered.
http://el34world.com/Hoffman/Blues_Junior_Tube_Board.htm

 Had a question. I have already installed some straight wire in place of the pre amp ribbon cables (they failed because the connections broke due to me having the chassis out so much..stressed em I guess). In the instructions for the tube board install it says to slice the ribbon cables to connect to the sockets..I was thinking I may  just run straight wire or is that more trouble than it's worth?

Any other comments or advice on this mod would be appreciated. Thanks

[markmalin]

Hi.  Welcome :)


I've installed just regular wire in place of the ribbon cable on the Hotrod Deluxe amps before.  Here are a couple suggestions.  And I would just do the single wires if it were me, rather than trying to splice into the ribbon cable. That sounds like a pain.  Just note the suggestions:


- swap a few wires at a time (or one ribbon cable at a time), then fire it up and test.  This way if something goes wrong you'll have the fewest possible number of changes to debug
- whatever you do, discharge the caps and unplug the amp before you do anything inside.  So if you're swapping a few wires at a time then testing, discharge the caps and unplug the amp each time.
- be careful you don't overheat the traces.  These boards are notorious for the traces and pads lifting if you heat them up too much.  Ask my how I know... ;)


Mark.

[73fender]

Thanks Mark, great ideas. Yes the traces are nerve racking to solder around, I've learned the hard waty too. One reason this will be my last pcb board amp.

[EL34]

Blues Juniors sound good but the PCB is a pain