That sounds logical of course, *but*...

There are three sensors with three pins each.
Each has one pin to GND, one pin via a common
inductor ("W1" ?) to power, and *ONE* pin each
connected to the IC. So, in some way, they
talk to IC via one pin for each sensor. And there
os one sensor for the wheel and one for each
"direction" of movement.

So my bet is that this are some kind of sensors
with some builtin logic.

Well, maybe better to breadboard a sensor and take
out the scope...

Jan-Erik.


Guillermo Rodriguez Garcia :
>You don't apply "power" to a sensor. An IR sensor is just
>a photodiode whose response will vary depending on how much
>light it receives within the IR band of the spectrum.

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