I have a basic 2 1/4 tac from Vans, the electric type, IE TACH 3500, with a tranducer IE VTACHGEN2. On Sat, half way into a flight the tach went to 300 rpm, and there was no response when the prop was adjusted or throttle moved. Back at the hangar the instrument had power to it and using the provided trouble shooting information it appears the tach is shot and the sender is good. I installed it 01/08/07 and it seems a little soon to ****-out, but maybe not. I plan on calling Vans on Monday to get a feel for these instrument's track record, but if anyone has something to add I would welcome your thoughts. Thanks, Pat