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Testing antenna coax

BCasto

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#1
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.
 
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#2
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.
 

BCasto

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Messages
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Morrisville NC
#7
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?
 
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#9
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.
 
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#11
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!
 
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