name of antenna wire gizmo hat goes outside the house?

Factual Questions
1

I don’t have cable or satellite TV. I rely on over-the-air broadcasts. This has worked fine until lately.

I paid someone to go up on the roof and re-aim the antenna and check the wiring. This fixed things fairly well for two days, and then we lost almost every channel. The guy who went up on the roof seems unwilling to admit that anything he did might have shifted or come undone.

He did suggest that the little gizmo on the outside of the house that connects the antenna wire to the wire that goes through the wall might need to be replaced. I could do that if I could find the gizmo in a store or online, but I need the name of the gizmo. It seems to have a thin insulator between the indoor and outdoor wiring. It is grounded.

So what is it called?

2

Surge arrestor?

3

Thanks. That could be it. I’ll see what I can look up under that name.

4

A picture would help, but maybe coax ground block or coax surge protector.

5

Balun transformers sound like your description also. Used for impedance matching in antennas.

6

Thank you, markn+. Pictures on the Internet of coax ground blocks look like what I have.

7

Robert: Irrespective of what kind of doodad you replace, don’t forget to cut off your wire connectors and replace them. Corrosion there is often the source of antenna problems.

8

I highly recommend this. I live in the suburbs and during a recent reroofing, I opted to remove the aerial from the roof and put one of the smaller digital antennae units in the attic space. That improved the signal quite a bit, but when I ran new coax from the TV to the antenna, I got literally 3x more stations. Now most of them I don’t want, but it showed that old wiring and setup really was messing up the digital signal. So perhaps the coax got a bit pinched during his work and that explains the full signal loss?

If possible, I would just run a fresh coax line and call it a day.