inverting a voltage?

[media at mail1.nai.net]

At 10:06 AM -0700 07/07/98, matt wilson wrote:
>i need to invert the voltage at the trig out of a korg sq10 so i can use
>
>it with "normal" gear.
>
>advice requested for this simple mod. i can't find it anywhere.

I found this in my files:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
There was someone asking about a circuit to generate voltage triggers from
an S-trigger out.  Well, here's the ASCII version of the circuit that
appeared in the March 1982 Keyboard  (Kraftwerk on the cover!)  Note that
this is for a 0/9v v-trigger.  If you need 15 volts, I'm sure it's a simple
change.


This will produce a voltage
trigger in response to an
s-trigger out.  The trigger                 Off
voltage will be 0 or 9 volts.            ___o       ___________
Close the switch to use, open           /          | 9-volt    |
it to save the battery life.     |-----o    o---- +| battery   |-- ground
                 ________________|          On     |___________|
                 \               \
                 /               /
             10k \           10k \
                 /               /
                 |               |----------------------- to tip of jack
                 |               |                        sleeve to ground
                 |    100k       /
      ___________|___/\/\/\___|/
      |                       |\   2N3904 or equivalent
 1   -|-  S-trigger              \
    _____     in                 |
 2    |                          |
      |                         ---
      |                  ground  -
     ---  ground
      -