Tach Signal, How to test... Options

[jim_hoyland]

How can I use the multimeter to determine whether a coil is outing out a tach signal ?

[914forme]

Some Multimeters have a tach function also.

If you want to "see" it, then oscilloscope is your best option. As it can be setup to show the wave as the field collapses and then re-establishes.

Or a 12v light hooked up to the terminal. I made a small LED trouble light with a 12v LED some long leads and an old BIC pen. That would work also, why do I like it, extremely small load when compared to the older incandescent lights. That makes it good to test low amperage circuits also.

BTW, You can spin this by hand the trick is to make sure nothing is in the combustion zone to cause the engine to catch and fire.

If you do it with the engine running, Even at 800 RPMs that little light will be flashing at 1600 times per minute. Or ~27 times a second average human can see 150 transitions per second. So you should be able to see the flashing of the light.

1600 flashes a second to Beats per minute and you would be invent a new genera of metal, Plaid Metal (IMG:style_emoticons/default/aktion035.gif)