[Username1]

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Those little pieces of sheet metal formed into a kind of "c" that was tight enough to
hold the power cord in place were very common years ago. My shop use to install
dozens of them on AM/FM clock radios notorious for having poor reception on FM.
They did work, and work very well, especially if you were in an otherwise strong
to mid- signal area. They could not perform miracles but worked so well we
always had them on hand. I have no idea what they were called, we had
boxes of them as we did warranty work on a few clock radio brands.
You can easily make one out of sheet metal, and use a piece
of plastic from any flexible food container as an insulator.
If you look inside the radio, you often find that there
is NO FM antenna at all, just a wire running to that
screw terminal, so that "gimmick" was the antenna.

Part of the insulator's job is to prevent the metal from
chafing through the line cord, so keep that in mind.
The insulator was longer than the sheet metal
that held the cord.

It works by magic, kinda like chicken soup
on the common cold.....

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