During support for a marathon yesterday, I experienced a rather strange failure mode in my TM-D700A. After hours of successful repeater operation, the radio locked up with the display going dark. Subsequent testing shows that the failure only occurs when attempting to set a sub-audible tone frequency on VFO A. (There is no beep on pressing [F][T.SEL], the display goes dark about two seconds later, but the microphone buttons remain lit.) The only way to recover the radio is to cycle power.
I have attempted VFO and Full Resets (both front panel and button) without success.
Has anybody else seen this and is there a way to recover?
Thanks and 73,