On Sun, 23 Nov 2003 15:51:08 +0000, Tommy Gilchrist
Good. If you build something ugly out of Meccano, it will still be
more reliable than the commercial sort with the motor inside the drum.
These things are expensive, yet horribly unreliable - especially if
frequently used, as they tend to overheat.
A worm drive from the roller shaft to a pinion wheel will allow you to
fit microswitches for limit stops, despite the multiple revolutions to
unwind the blind. You'll also need two relays, which you can get from
the same scrapyard you visit for a car door electric window motor.
Die Gotterspammerung - Junkmail of the Gods