It was about 4 deg-F at 17,500 MSL in the wave yesterday when the display on
my MicroAir 760 radio went blank. I confirmed that the radio still worked
by switching channels to AWOS, one click to the left, and receiving the
airport weather report. I couldn't tell if the transmitter still worked
since mine was the only aircraft in the air at the time.

I forgot to check after putting the ship away if the display had returned.
Is this normal behavior?