I have two ways to read RPM in my plane currently. I have a traditional cable driven mechanical tachometer, and I recently installed an EDM 800 that reads RPM with a Hall effect sensor on one of my magnetos. I haven’t flown it yet but when I did a ground run to test the installation I noticed the two didn’t quite agree.
Should I trust the electronic reading more than the mechanical, assuming the mechanical may be inaccurate due to cable wear, or are there other factors at play? I haven’t had a chance to test with an optical reader yet, that’s on the list. My question is more to the operating principle of each and if it biases towards one or the other.
Should I trust the electronic reading more than the mechanical, assuming the mechanical may be inaccurate due to cable wear, or are there other factors at play? I haven’t had a chance to test with an optical reader yet, that’s on the list. My question is more to the operating principle of each and if it biases towards one or the other.