14-09-2020, 02:11 PM
Hi Duncan
Another report back regarding iPhone based rev counters. This one the free “strobe light tachometer”.
This was very good. I wanted to check the speed of my electric drill so that I could then attach it to the speedometer drive to know if it was recording correctly. All you need is a surface perpendicular to the rotation (a sanding disc in my case) with a white dot or line on it. Pointing the flashlight at the disc it strobes to the frequency shown on the screen. Altering the frequency until the dot appears still gives you the revs/minute.
Turned out my 1500 rev/min drill only turned at 1100.
I’ve yet to try it on the engine and guess I would need a clear sight line to the flywheel (or cam pulley). Unfortunately not something you can use as you drive along☹️.
Cheers
Howard
Another report back regarding iPhone based rev counters. This one the free “strobe light tachometer”.
This was very good. I wanted to check the speed of my electric drill so that I could then attach it to the speedometer drive to know if it was recording correctly. All you need is a surface perpendicular to the rotation (a sanding disc in my case) with a white dot or line on it. Pointing the flashlight at the disc it strobes to the frequency shown on the screen. Altering the frequency until the dot appears still gives you the revs/minute.
Turned out my 1500 rev/min drill only turned at 1100.
I’ve yet to try it on the engine and guess I would need a clear sight line to the flywheel (or cam pulley). Unfortunately not something you can use as you drive along☹️.
Cheers
Howard