TV antenna adaptor

My new VHF antenna has an adaptor with two short insulated wires at one end and a screw-on attachment for the co-ax at the other end. The two wires are meant to be connected to the arms of the antenna, using the wingnuts on the antenna, and the co-ax is connected to the other end of the adaptor by a screw-on device that grips the shielding of the co-ax with a threaded cylinder and screws to the adaptor with a threaded hex-nut.

My question, before I caper around on the roof like a twenty-year-old, is this: The resistance between the two wires, even without the co-ax or the co-ax connector being connected, is zero. Unmeasurable. This cannot be right? Can it?

Reply to
T.T.
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"T.T."

** Yes it is right.

The tiny windings of small RF baluns have negligible DC resistance .

One needs pretty fancy RF test gear to measure the actual impedance in the VHF or UHF bands.

........ Phil

Reply to
Phil Allison

Thanks for that. I was checking to make sure that I had not shorted the shield to the conductor, and confused myself no end.. Up onto the roof.

Reply to
T.T.

Don't forget to get the polarisation correct.

Reply to
Mark Harriss

** Yeah - or else you will have to wear polarising glasses when you watch the telly.

............ Phil

Reply to
Phil Allison

Yeah you can get 3D with two antennas at different polarisations and those coloured glasses.

Reply to
Mark Harriss

sounds like an "F" conneector.

It's right. the transformer inside the unit is designed for VHF and has very little wire in it. as a result it has negligable DC resistance.

Bye. Jasen

Reply to
Jasen Betts

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