When I brought the H-field on, and selected auto gain, that was the last I'd seen the yellows blink except at start up.
But it is now in an opaque box that is out doors, sealed up, so maybe it is doing it and I just don't notice it any more.
All the great light action (sort of like slot machines at the casinos in Vegas, trying to get my attention) is on the controller board, right where I can watch it blink away.
The E-field amp board is right near the controller, so I'm able to watch it a bit more, and it indeed may blink a yellow light (not all the same) every now an again.
PS, I believe in math and statistics so I've not fed the seductively lit and even more attention-grabbing sounding slot machines. They are just money grabbers.