I guess the missing part of the original question was some explanation of
how you hear the wobble. Are you in a Sideband or CW mode that would let
you hear the carrier shift?
If you are listening in AM, it would almost have to be a beat note with
another station as you would not hear any kind of low freq modulation or
If you are listening in Sideband or CW, then I think of another scenario.
Some AM stations send information that can be displayed on the receivers
display. I was thinking that some of that was low speed data sent by
essentially shifting the carrier. It's been awhile since I saw that and
perhaps they do it some other way now with the advent of AM stereo as well
as the HD radio (as they like to advertise it) for AM stations.
Anyhow, a few more clues would help a lot.
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