It's better to measure RPM under stable light source. Doing it under sunshine can be much better.

Chen

Just cancel the RPM function then enter it again to measure the RPM, or perform another functions.

Chen

The "peak" function is very helpful!

I've been using it outside, in bright sunlight.

Again, mine measures rpms when the prop is stationary: it is not predictable.

I suspect I must learn exactly how to use it.

Just put the spinning propeller in front of the sun, then point the measuring port to the rotating prop, be sure to keep 5-10 cm or 2-4 inches away from it.

Chen

That's my method. I'll try again, tomorrow. I do really like the servo test functions!

Do you have GWS MT-1?

Pls order from your favorite LHS or go: www.caliberhobby.com

It's at promotion priced $30 now, but sooner or later back to $40!!!

O.K., I give up on the tachometer function: it is either too difficult to use, badly designed or mine is defective.

As a servo tester, it is perfect.

So, DON'T buy it for the tachometer function.

I should add, I spent 30 minutes yesterday and 30 minutes, today, in broad daylight, trying to get the tachometer to perform in any reliable or repeatable manner.

I am sorry this better function caused you inconvenience to use.

So, GWS should not put too many functions all in one equipment?

I remember, some one said: " Simple is the best! "

I think it is a wonderful function to have SO KEEP IT.

IN MY CASE, either it is defectively manufactured, defectively designed or I'm just too stupid.

I had several friends try it with the same result, so I merely "suspect" MINE is defective.

SUM: KEEP IT, IT'S A WONDERFUL FUNCTION IN AN OTHERWISE VERY, VERY WELL DESIGNED, EXTREMELY USEFUL DEVICE.