I've been trusting one for a long time. Nothing to calibrate to so you have to go by ear and some common sense to use too. As long as they're taken care of and not bent up I think they're good.
I have checked it against a Stihl electronic tach and it is certainly close enough for my purposes. Nothing to go wrong as long as it is not dropped or stepped on.
I have checked it against a Stihl electronic tach and it is certainly close enough for my purposes. Nothing to go wrong as long as it is not dropped or stepped on.
Have been using one for 30+ years and never had a problem. I use it for both RPMS and Hertz when I’m adjusting generators and don’t have my meter in the field. Accuracy is dependent on the user. With this meter your eyes and ears tell you when your right, it does take practice, but everyone is different.