Vintage Synth Repair

At 19:43 Uhr +0000 21.06.2011, Boddington wrote:

> The load on the Trilogy appears to be different though.

How do you know that?

> It needs to produce several more outputs on those jumpers.

Which doesn't mean a thing unless you know how much additional power those
outputs draw. The load could even be lighter!

> I still don't know what the value is for the T63 but I suspected it would be
> at least 20 per winding when factoring in the wave rectification's RMS, etc.

There are several misunderstandings here.
If you have a circuit with a higehr load you usually go with  transformer
with a higher wattage, not voltage.
Second, the effective voltage will measure significantly higher without any
load. A 15V transformer with a non-connected secondary will measure around
21 volts.
So what you need to measure is the voltage of the secondary while the
circuit is under its typical load.
While you're at it you could also measure the actual load; this will give
us a good idea what wattage the transformer could be.

From my calculations it should be a 2x15V transformer. Using a transformer
with a too high secondary may kill the regulators because the larger
regulation overhead has to be dissipated into heat.