Chuck,
The best way is to just measure an individual element with an SWR meter,
or even better, an antenna analyzer. Feed the test antenna element with an
even multiple of a half wavelength of the coax you prefer. Make sure the
element is set up in a typical operating environment, that is, mounted on
its mast and preferably the mast clamped to the side of a tower or another
chunk of iron similar to a tower. You can do this with the element at eye
level just to get an idea of how it operates. Not a precision set-up but,
true, but will get you in the ball park.
Yours may be 100 ohms but all the folded-dipole types I ever played with
were close to 50.
73
Al, K9SI
Date: Sat, 17 Apr 2004 22:25:06 -0400
From: "Chuck Kelsey" <[EMAIL PROTECTED]>
Subject: Re: Re: Decibel repeater antenna question......
Just curious... how did you determine that each element was 50 ohms?
I was always of the understanding that the Decibel design, each element was
100 ohms. Also, that the later versions of Decibel arrays used 50 ohm and 35
ohm cable, no 75 ohm stuff.
Chuck
WB2EDV
----- Original Message -----
From: "Al Wolfe" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Saturday, April 17, 2004 6:20 PM
Subject: [Repeater-Builder] Re: Decibel repeater antenna question......
<snip>
and every one had an impedance of 50 ohms at the individual
> element. An odd multiple of a 1/4 wavelength of 75 ohm coax takes it to
<snip>
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