XYGAX wrote:
>>
>> Paint a white line on the flywheele and use one of those reflective opto
>> switches then count pulses it also has the advantage of being a non
contact /
>> no mechanics interface
>>
>> Cheers Steve.....

>Most Industrial sensors don't respond above 500Hz
>this is done to limit noise
>peter@cousens.her.forthnet.gr

Peter,
However, most diesel engines don't respond (for long)  above 500Hz * 60secs
= 30,000 RPM
This is also done to limit noise  :-)
Gerry Cox
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