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Old 24 August 2011, 17:24   #31
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Was the antenna conected to the feed? because a short is perfectly acceptable with an inductivley coupled antenna
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Old 25 August 2011, 11:53   #32
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The antenna will show a short. That's why to check the cable you need to disconnect it at the antenna and at the radio. Then you should see infinate ohms on a multimeter across the centre pin and the body of the PL259.

The multimeter screen should read the same as when the meter is on and the probes are not touching anything. Touch the two probes together - that's what you'll see for a short.
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Old 25 August 2011, 12:11   #33
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Quote:
Originally Posted by captnjack View Post
On my multimeter this would be a full short then. When there is no continuity the screen reads "---" or something like that. Basically you want infinite ohms of resistance between the center pin/connector and the outer body of the connection/sheath of the coax.
Agree. On my multimeter 0 is a short and 1 is infinity.
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Old 26 August 2011, 07:36   #34
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Many vhf antennas are a J aerial or a version of that configuration. In this case the screen and feeder are connected, one each, to the legs of the J at the bottom of the J so when checking the continuity using a multimeter a full short will be recorded. Therefore this test is not a valid way of checking since a cable short fault will give a similar reading on the meter.
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Old 26 August 2011, 11:54   #35
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The Metz is internally grounded and will, in common with most antennas of this type, look like a short to a multimeter. Thus, you must disconnect the cable in order to test it with a multimeter as described.
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