A few years ago I was traveling to many sites in Romania, installing new medium wave (AM broadcast) antenna systems, while an associate installed new Harris solid state transmitters. At one site, I had to retune an existing antenna to 50 ohms, j-zero, from the approximate 75 ohm setup it used previously. I retuned the network but ended up with a reactance that called for about 18 microhenries of series inductance to cancel. I asked where I could find such a coil and was directed to a much cannibalized transmitter in a back room, and found a nice rotary inductor that fitted the bill.
It was obviously a short wave transmitter and, when I inquired as to what it had been used for, I was informed that it was a jammer to interfere with Radio Free Europe. Located right in the city, it would have made life difficult for most people trying to listen.
We put the coil to better use and had a good laugh.