I know that my Hobbico tach will read 3600 when pointed at a flourescent light. However, it will also read 3600 when pointed at an incandescent light!!!!
I was running an electric system indoors and wanted to read the speed while I was monitoring the watts with my Whattmeter. All I got was erratic readings. I had turned off the flourescent light after turning on the incandescent light, figuring the f-lite would mess with the readings. What a surprise to find that it would read the i-lite @
3600 as well.So, beware if not using natural light to take tach readings!!!!!!!!
David