tachometer AGAIN

[Bootlegger]

 I now have TWO Hanger 9 tach's and neither one will turn off, the second one is doing the same as the first.
 I called and they sent a second one, and it does not turn off either, both show up to a 9 bladed prop as well as indicating the speed of the model.
 Anyone else having this problem?   The tach is their part# HAN 156