What the heck is that guy doing?

I've been trying to get the dog's invisible fence working again. The wire has been cut in at least two places. There's about 100K ohms showing on the wire. I found one break where they trenched in new cable service last year and patched that. My patching involves sliding a piece of PTFE tubing over the wire, cleaning it up, crimping on a butt joint connector, soldering firmly with a torch, then sliding the PTFE over the joint and silicon caulking the ends.

There's one more break and I'm having trouble finding it. The method is to put an RF choke in parallel with the loop at the transmitter, then tune an AM radio to a point where it receives the signal and walk around looking for where the signal drops out.

Unfortunately I have to get about 2 inches from the ground to pick up the signal. So I've been either bending down or crawling along the 1500 feet of border of our lot for a couple of hours on two occasions this week. Still looking for that 2nd break.

If worse comes to worst, I'll have to start halving the loop, pulling a long bit of wire to the halfway point, digging the wire up there and measuring the loop resistance. Repeat until I find the problem. That could get very troublesome, and I don't know if I have a hunk of wire long enough to reach halfway across the property.
It is important to develop a history of justifications for eccentric behavior for future use during competency hearings. Just make sure you minimize your audible conversations with your very short, invisible friend.
Okay, that was a lot more brilliant than "ask the network guys if they have a TDR you can borrow."