[TenTec] Omni VI logic board

[Peter Bertini]

My guess is you have a bad encoder, or a bad switch on the front panel.  If
one of the switches controlled by the push buttons remains keyed it will
raise an interrupt in the software and through the processor into a
loop--that routine will continue until the problem is resolved.  If you are
seeing data signals on the proms and processor then I'd suspect the logic
board is okay.

Try removing the plugs that are connected to the push button matrix on the
front panel first and see if that clears it up so you can at least use the
main tuning to change frequency.  Been there, done that... I've seen
leakage resistance on a Ten Ten Omni switch cause the same issue!  It does
not take much.