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« on: October 26, 2015, 1403 UTC »
Had to travel out of town the last 2 weekends. When I returned from the first trip, the ferrite NDB loop was not working upon my return, and an autopsy revealed that an electrolytic cap had exploded inside the loop head. Although it was new and very conservatively rated for both temp and voltage, it crapped out, possibly due to a hard freeze we had that weekend. No biggy, shit happens, and it was an easy repair.
Upon firing up the loop after the 2nd trip, everything seemed fine on the power-CPU-stepper side of the loop, but there was no RF output. A 2nd autopsy revealed that all 5 wires coming back from the winding on the ferrite rod had apparently been chewed through multiple times. This includes the ground from the winding center tap, which was a length of shield from an RG174 coax. A large percentage of the litz wire serving was missing.
This really creeps me out because the entire assembly is absolutely sealed and waterproofed. All cable entries are via sealed cord grips, and the loop proper is contained in a waterproof PVC housing, mated to the enclosure via a PVC bulkhead fitting. There is no point of entry for a critter, guaranteed.
What am I dealing with here?
My only conclusion is that I have been attacked by a Quantum Mouse. Even my trusty mouser jDog is scratching her head over this.