Thanks
Yes, I probably did not word that question well. We had a tach gen. that was croaking, it went up to 97, down to 50, with engine out tone. The AC gen. was kicking off and on line. Old phase 2 bird, so we would get an AFCS chatter in the controls as the AC gen came off line before the invertor picked up the load. (for maybe one second) Reset master caution all good, then N1 tach would drop below 50, engine out audio, control chatter again. Our techs just finished up some research, looks like signal for the AC gen to come off line does come from the N1 tach gauge. Thanks the responses, this is a great forum.