[sdiy] S-trig -> V-trig

[Dan Gendreau]

> do anyone of you have schematics for a S-trig to V-trig
> converter?
> I suppose I must have a +5V (or higher?) voltage taken from somewhere, and
> have it
> turned on everytime the S-triggers grounds. Any suggestions for a simple
> solution?

Simplest way I can think of:
An inverter with a 10k pullup resistor at its input.
When the switch is open, the pullup presents 5V to the inverter and the
output is 0V.
Then the switch is shorted, the input is 0V and the output is 5V.

The same trick could also be done with an opamp. It requires more resistors,
but the advantage is that you could put in a pot to select the trigger
voltage.

Anyone else have a better way?

You can probably do it with a single transistor, but I have to work that one
out on paper first. My transistor skills are a bit rusty... heh.

-Dan G.