Putting on my old EE cap, it is worth noting that the subject of Hall
effect sensors is at once very simple, yet very complex.
These little guys are sold by the millions every year, there are
at least a dozen in any recent car.
The sensor itself is absolute simplicity - just a small strip of semiconductor
with electrical contacts on four sides.
The problem for OBAM builders is that there are possibly 1000 different
commercial sensors available widely varying in size, cost, sensitivity, and
complexity - bare sensors all the way to microcomputers.
The random orientation of the magnet in the Airmaster just makes life
a bit more complex if you want to detect its passage with your own
sensor. It would have been easiest for us to have an exposed, buffered
TTL pulse line out of the Airmaster controller. Failing that, you can buy
the Westach Aviation grade, potted, rugged sensor, or buy a raw sensor
and pot and mount it yourself.
So many choices, so little time to explore!
As for Jim's problem, I sympathize, but I don't know the details. Possibly
a bad connection or a waveshape issue. Strangely or perhaps not, I find
I am using my little digital scope quite a bit with my Europa ;-)
Ira
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Ira N224XS
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