Hi,
How can I test my 1/4 wavelength antenna (for my car?)... when I hook it
up to my radio I see no better signal throughput to the repeater then
with my rubber duckie (even at 7 watts). however.. with my j-pole
antenna my signal is crystal clear...

Any thoughts?

"Matt" wrote

Any thoughts?

Quarter wave antennas need a counterpoise to work properly --- are you testing
with the antenna mounted on the car? (It won't work properly sitting on the
floor of your shack, or on a wooden desk.)

If the antenna IS mounted on your vehicle, then you have a feedline (coax)
problem (shorted coax, open connector, etc.).

73, de Hans, K0HB

Quarter wave antennas need a counterpoise to work properly --- are you testing
with the antenna mounted on the car? (It won't work properly sitting on the
floor of your shack, or on a wooden desk.)

If the antenna IS mounted on your vehicle, then you have a feedline (coax)
problem (shorted coax, open connector, etc.).

73, de Hans, K0HB




Yup.. it's on the roof of the car. I was kinda leaning towards damaged
coax or connector, but was wondering if there was something I could do
with an ohm meter or something to determine where the issue might be?

~ Matt

Matt wrote:

Yup.. it's on the roof of the car. I was kinda leaning towards damaged
coax or connector, but was wondering if there was something I could do
with an ohm meter or something to determine where the issue might be?

If it's a true 1/4-wave antenna, it won't have any matching
transformer. So you should see very low resistance from the center pin
of the coax connector to the antenna element, and a very high
resistance from the center pin to the shield. This will tell you if you
have an open or shorted cable.

Art N2AH