[sdiy] MG-1 How to get -12v from TIP30 and 741?

[synth1 at airmail.net]

> I still don't understand how these parts are supposed to equal -12v and
> -11v, but at least I can measure a few things. I am extremely grateful
> for your suggestions.
>

The -12V is "divided down" (up??!?) by the 2 resistors. The 741 is just an
follower/buffer, to provide a "current boost" from the 3 resistor divider.

-11V is because the TIP30 is 1 base-emitter junction "drop below" -12V,
with is *about* -11V but probably more like -11.3V.

Mouser.com has 741s.

Paul S.