YWX V-Tronix VHF Whip Antenna - Resistance Expected ??

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john0740

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I am testing what appears to be one of these (it's on the mast so not seen it up close) for a friend and can't find documentation.

Would anyone be able to advise what dc resistance this should have - is it one of these types with about 10kΩ or fully dc-grounded providing a dc short cct (or something else)?
 
john0740 said:
I am testing what appears to be one of these (it's on the mast so not seen it up close) for a friend and can't find documentation.

Would anyone be able to advise what dc resistance this should have - is it one of these types with about 10kΩ or fully dc-grounded providing a dc short cct (or something else)?
Click to expand...

IIRC they have a resistance, I went through this a few years ago, its on their website somewhere. On mine the groundplane copper strip had corroded
 
I'm up at the workshop with one aerial and two meters, and getting nonsense. I suspect the meter batteries, so will take it all home later and try again this evening.
 
Measuring DC resistance on such an antenna as this isn't a great way to figure them out. It's not DC we're dealing with, but AC, and at very high frequencies. And with many variants of system of inductors and capacitors at the base of VHF whip antennas, being definitive about DC resistance or continuity isn't so informative.
There are other instruments for this task, though less commonly found in a toolbox.
 
I have a V-tronics antenna - not sure if it's the same model - and it very clearly says in the instructions there is a 10k ohm resistor across the leads. It's very useful as open circuit really means that and a short indicates a probable connector problem ... ...
 
Hi
Yes, it's the 10kΩ value I was after for dc resistance which is very handy for a basic connectivity test.
I've done the RF measurements already; evidence pointing towards a cable fault.
Thanks
 
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My digital meter gives the following - all Ohms

Disconnected cable core 3

Disconnected outer 2

Total connected anywhere between 30 and 2k, but all over the place.

And changing the batteries in the analogue has blown the fuse, so no help at all unfortunately.
 
MM5AHO said:
Measuring DC resistance on such an antenna as this isn't a great way to figure them out. It's not DC we're dealing with, but AC, and at very high frequencies. And with many variants of system of inductors and capacitors at the base of VHF whip antennas, being definitive about DC resistance or continuity isn't so informative.
There are other instruments for this task, though less commonly found in a toolbox.
Click to expand...

As Hoolie says, Vtronix actually tell you to measure across the cable to check for 10 k ohm resistance as a simple check.
More here, http://www.ybw.com/forums/showthread.php?462080-Testing-a-new-VHF-aerial/page2
 
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