Post by thread:[EE] Stepper motor asanencoder-andaccidentalmicrop

> Is your application secret or can you share it with us ? It's for an art installation. A friend wants one moving spotlight to highlight a series of pieces in sequence, as directed by the soundtrack. Looked at a variety of options, this way seems the tidiest and user-friendliest

:: friend wants one moving spotlight to highlight :: a series of pieces in sequence Sounds an ideal wheeze for solar cell positioning, prgramming satellite tracking, curtain positioning. Colin -- cdb, spam_OUTcolinTakeThisOuTbtech-online.co.uk on 10/11/2008 Web presence: http://www.btech-online.co.uk Hosted by: http://www.1and1.co.uk/?k_id=7988359

> Could you check your logic on Fig. 2? It's not working the way > that I would expect it to. Do you need a pull down resistor in the > present configuration? Ah, good point. The diodes are isolating INT0 from the low of the comparator, so a pull down would be needed. Without a pull down the input is effectively floating high when the driver is low There'll be a voltage drop through the diode to consider, and the pull down value will have to be large enough not to divide the post-diode voltage below the input L-H threshhold. >10k should probably do Thanks Gordon I've updated the page. I'll also get around to Russell's long-tail pair idea today and add the results of that experiment