Ah, the deadly TT4 Hang....if it was a problem that I could replicate, it would probably be a lot easier to debug....sadly, its underlying cause has remained a complete mystery. It can take months to recur, never happen at all, our happen much more frequently that anyone would care to think about! Bob Bruninga used our MTT4B design in the Naval Academy CUBESATS, and he used a 555 ( actually a 556, but the principal is the same) to do a forced reset on a daily schedule.? Some enterprising gentlemen in Australia were using inexpensive programmable power timers to restart their systems. I have come to the conclusion that remote digipeaters should be treated just like repeaters, and you should have a remote mechanism for shutting them down or restarting them if they start acting up. This is one of the reasons we built the little known DTMF REMOTE (). This allows you to control 8 logic level outputs via DTMF on any 2 meter frequency, so you don't have to rely on the normal input frequency to your digi or repeater, in case its being jammed, accidentally or intentionally.?

My other mysterious events are MAX232 chips that suddenly and for no apparent reason overheat and self-destruct. There are millions of internet posts about this, but its still a mystery.

Stephen's technique of letting his TT4 just cool down for a few days ( Which I suspect may have included some moments of blasphemy, profanity, obscenity,? and other general abuse of the TT4) seemed to work fine...the thing just went on strike for a few days. No one knows why.?

73,

Allen AF6OF

(p.s., I am sure Stephen is a perfect Christian Gentlemen who would never use foul language against an innocent TNC)?