Testing antenna coax

[BCasto]

I have 4 antenna leads from the attic to my radio shack. Unfortunately the labels are gone and I don't know which is which. What tool or method do your recommend to identify each coax run individually? Thanks.

 

[mmckenna]

Ideally? Pros would use a toner and inductive pickup amplifier. A decent set will cost around $100.00

Easier approach is to short one end of one of the cables and use a multimeter to find the short.

 

[n0nhp]

This with a couple of adapters will do the trick
https://www.lowes.com/pd/Southwire-Coax-Continuity-Analog-Volt-Datacomm-Tester/50278121

$20 plus the cost of the adapters

 

[mmckenna]

There ya go, that'd work. Good find, N0NHP.

 

[cmdrwill]

But, you would have to disconnect the coax at the antenna and put the 'dongle' on the coax.

There are other ways,

 

[BCasto]

This with a couple of adapters will do the trick
https://www.lowes.com/pd/Southwire-Coax-Continuity-Analog-Volt-Datacomm-Tester/50278121

$20 plus the cost of the adapters

Thank you. That device is for cable TV installations with the typical screw-on connector. Could I use it with BNC connectors?

 

[BCasto]

Ideally? Pros would use a toner and inductive pickup amplifier. A decent set will cost around $100.00

Easier approach is to short one end of one of the cables and use a multimeter to find the short.

I am not skilled is such things but do have a multimeter. How do I short one of the of the coax cable?

 

[mmckenna]

Thank you. That device is for cable TV installations with the typical screw-on connector. Could I use it with BNC connectors?

Yes.

 

[mmckenna]

I am not skilled is such things but do have a multimeter. How do I short one of the of the coax cable?

You can likely use a short piece of wire. Just something to make a good electrical connection between the center pin and the outer shield.

Do one cable at a time. Make sure both ends of all cables are disconnected from the antennas and radios.

Use a continuity checker or multimeter to figure out which cable is showing a direct connection between the center pin and the shield on the far end.

 

[BCasto]

Thank you all. I now have options and a plan.

 

[majoco]

Actually I wouldn't short the far end of the coax and then measure the resistance from the near end - what would this achieve if the coax is shorted braid-to-centre somewhere along it's length or in one of the plugs? Buy one of those cheap-as-chips 50ohm ethernet terminations and put that at the far end then see if you can measure its resistance plus maybe half an ohm - anything else is suspicious!