More Inductive Pickup

[Rodney Pratt]

On Thu, 30 Nov 1995 14:08:51 EST, you wrote:

>I was told that an inductive pickup (from a timing light) will
>produce enough current to flash an LED.  I have not tried this yet,
>however, I am wondering if the pulse width from a spark is long
>enough to "see".  What is an "average" length of a spark?

I recently used an inductive pickup connected to a H11L1 schmitt
trigger opto-coupler which inturn triggered a 555 in monostable
one-shot configuration. This circuit produces a clean pulse, with the
pulse width determined by the 555 timer RC combo.

One thing to watch, be sure to provide a suitable sensitivity
adjustment on the opto LED current so you can set a trigger
threshold,or you will find you pickup stray firings from the other
cylinders.
Rodney Pratt
Computer Aided Test Engineer
Mitsubishi Motors Aust Ltd.         rpratt at senet.com.au