My amp gauge is pulsing quite rapidly on my Citabria and I'm getting sort of a chirping feedback thru the radio. I can turn all electrical items off like turn coordinator and lights and it's less but still there. If I turn radios off and leave strobe on I can still hear a faint chirping thru my headset when the strobe flashes. An avionics guy I ran into said he thought it could be the diodes in the alternator. Does this sound like the first thing to check? Thanks.