Spray the coax lightly with some bitter apple spray available at most
pet stores. Slide garden hose over the coax. The hose keeps the bitter
apple spray from washing off. The good stuff will keep its taste/odor
for a couple months (YMMV). The dog will smell it, and *if* he bites
down, taste it right away. I've used this method for jumpers at my patch
panel to dane-proof them at my place.
My great dane has a taste for rope dipole ends and guy wire -- yes, guy
wire -- and she's bitten through one but thankfully not the other. The
spray broke that habit. And I suspect your neighborhood critters will
catch on too.
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