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> The solenoid will be activated for very short periods of time
> (roughly .2 seconds) rather infrequently (let's say an average of
> once every minute)

Jake, I just re-read your mail, and re the 0.2s have this suggestion

A circuit I use to power solenoid clock mechanisms has just a
capacitor to operate the solenoids, which are pretty hefty. I've
not measured the coil current but the DC resistance is 3 ohms

The attached shows how the solenoid is pulsed for about 0.25s.
These mechanisms are either 12V or 24V. The LM317 is there
to limit inrush current when the solenoids are fast-stepping at
2Hz (eg when the clock is put forward an hour). Normally the
clock is advanced every 30s. Using the capacitor means the
power supply can be much smaller than if it had to supply the
current directly. It does droop a little when fast-stepping but
not enough to affect the PIC. From memory the 12V solenoid
will pull in (weakly) at 8V and the 24V version (weakly) at 15V

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