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Old April 6th 05, 04:44 PM
Bruce W.1
 
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Dave Platt wrote:
In article ,
Bob Miller wrote:


For example, the rubber duckie that comes with my 2 meter Icom T2-H,
at 147 Mhz, has an swr of 3.0, and an impedance of just under 400
ohms, according to my MFJ 269 antenna analyzer. But the antenna works
fine on the handie talkie.



You might want to try repeating the measurement with the MFJ 259 held
up beside your head as if it were an HT.

I've been told that HT duck antennas are often tweaked for best match
and lowest SWR when used in this position, with a significant amount
of capacitive coupling to the user's head. Measurements of a couple
of 'em with my 269 seemed to support this - they "read" a lot better
in a "typical HT use" position than they do if the analyzer is being
held out at arm's length.

================================================== ======

That's the part that's difficult to measure. Some of my good HT
antennas that came with the radio, when tested alone on a good ground
plane, have lousy SWR. Yet these radios are fully capable of being
connected to an external antenna.

A perfect quarter wave is 36 ohms. Yet HT's are happy driving an
external 50 ohm antenna.

I do have a few telescoping antennas. This might be the best solution.
I was hoping someone made one built like a tape measure. A tiny SWR
meter that mounted between the HT and antenna would be a nice solution.

I'll admit I like to have the ability to at least jump over to the FRS
or the GMRS.