Re: A LEGO double-throw switch?

In lugnet.robotics, Steve Hassenplug (& others) wrote:

[snip a bunch of good ideas]

   Wow, ask a simple question... Currently I'm planning on using one switch that
is normally off, and when the forklift delivers a crate it turns it "on-fwd".
When the crate reaches the far end, it (the actual crate, btw, not the conveyor)
pushes a mechanical linkage (or trips a spring-loaded linkage if need be) that
pushes the single polarity switch back to "off". BUT... this is only likely to
work well over rather short distance, so I was looking for an electrical way of
solving this as well.
   Steve, using two polarity switches and "tuning" their relative positioning
you could make a "virtual" polarity switch who's deadzone would be as small as
you like it, I think.
   Dang, wouldn't you know it, still more uses for those blasted polarity
switches. Pitsco must *love* me...

-- 
Brian Davis