"Jo" wrote in message
...
In ,
Steve Taylor typed:

Why don't you close the loop and have proper position feedback ?


I was working with whatever bits and pieces were to hand. Any suggestions
on
how to provide a positional feedback loop with typical junkbox items would
be cool. Come to think of it....there is a component in the VCR that *may*
be a linear position sensor..possibly for mechanically detecting how much
tape was remaining on a reel during fast rewind. Not sure of the
resolution,
though. Any other ideas?

Jo




Maybe you could use a potentiometer, that throws over the full range of the
focuser. Then measure the voltage to show the distance.

Probably doesn't resolve enough though.

Col.
www.cjdawson.com