Fake tach signal for PM3 debug on bench

[kprice]

Is there a way to fake a Model C or Model D tach signal for debugging a PM3 on the bench? I have a few PM3 that are not working so I thought would poke around on the bench but I do not want to drag the flywheel into work to get a valid tach signal. Can I make up one with a signal generator?
The Model C appears to be an simple inductive pick-up but the Model D looks much more complicated....

Kirk

[Citroen]

If you have a scope you should be able to measure (amplitude and frequency) from the sawtooth wave that the tacho produces.

Paul Smith's erg monitor software works by hooking the PM3/PM4 tacho up to the sound card. You may be able to do something by sampling using that. You'll need to measure the voltage using some other method.

[kprice]

Thanks. I was hoping to avoid getting the flywheel ( at the club) and the scope (at work) in the same room....can someone tell the voltage of the tach signal for a Model C?

Thanks again.

[Carl Watts]

For the PM2 and the PM3 the easiest way to bench test is to get a spare Model C tach sensor and just use a magnet on it with it plugged into the Monitor.

If the PM2 starts up by just waving the magnet across the face of the sensor about 1 inch away it is working and the sensitivity of the input is also okay.

Same for the PM3, set it to Model C in the hidden menu and test the same. If it works then chances are it will work with the Model D input as well.

I also just use a multimeter and check the PCB from the socket to the Opamp on the PM3/PM4.

[kprice]

Great, that is easy for a even a Mech. E. to do....thanks.