Vintage Synth Repair

I have a E-mu B-3 that has stopped working. Iv'e tried changing cords 
along with tapping and wiggling connections. All without positive 
results. If anyone has a suggestion, I will read it. Thanks, 
Mark..............

>>I have a E-mu B-3 that has stopped working. Iv'e tried changing
cords along with tapping and wiggling connections. All without
positive results.<<

mark- this is a regular proteus chassis branded as a b3 module, right?
& when you power it up, no lights, nothing...?

try this: if you are able to, switch the unit on & listen to the noise
from the top of the case at the right hand end. you /may/ just be able
to hear a faint ticking from the power supply, which occupies most of
the right end of the chassis. this is bad.... :-)
in any event, it sounds as though the power supply has failed. I had a
proteus 2000 box fail like this last year, right before a gig. if the
fuse goes in one of these power supplies, don't waste any time
replacing it. by the time the fuse goes, it's toast.

you have a couple of options, depending how good your local techs are.
a new power supply of exactly the same type (SDA3021) is not
impossible to find, but any switched-mode power supply with the right
outputs & that can be persuaded to fit in the box will do. I have used
units from astec, skynet & so on, to fix a variety of emu modules
going back to the original plastic-cased proteus 1.

as I say to my engineering colleagues, whenever they encounter a dead
power supply, "these days, everything uses 12s & 5s." there is nothing
special about this power supply except the shape of the package.

the one that's fitted in all the various p2k-type boxes (from the
audity on up), rather conveniently, is labelled so you can see which
connection carries +12, -12 & +5 volts to the main board. the current
ratings for these three outputs are printed on the side of the
mini-transformer.... it should not be beyond a comptetent tech to
replace this with either a similar or an identical unit.
failing that, you can scour ebay & the like for an empty emu chassis;
these come up from time to time. you can use this as-is or move it's
power supply into your b3 module, a five minute job. the latter is
preferable in most cases (no pun intended) when your primary rom is
the one the case is styled for, & when the processor ram is full of
presets based on that rom. these, btw, are probably intact in your
machine.

hth-
duncan.