I've been given a wavefront travel case Theremin to repair.... seems the
power supply is dead, it has a 3 pin DIN connector alas I am not 100% sure
as to what the voltages should be on these pins? Is there anyone out there
who knows? I tried e-mailing the company however haven't received a reply.

Hi,

Have got the Theremin working, tho I'm still unsure as to the correct
operational voltage. I used a 7 volt battery on the non-working +V line and
lo and behold the thing lights up and plays just fine. as folks have pointed
out, the LED resistor points to the +V line being 5 volts. The LED is
actually a panel mount LED unit which has written on the side 5V, 20MA -
though this still means the resistor is a bit low for 12V, also a bit high
for a 5V supply. There is an IC which is fed off the two supply lines which
( LM13600, according to the data sheets) requires +/- 15volts.

I guess the main thing is its working and building a PSU for it will be no
problem.

Thanks for your help.

Colin