General Category > Amateur Radio

HT Antenna

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Stretchyman:
It's the wrong length.

Str.

Matt285:
Yes. I tend to agree.

Stretchyman:
Indeed, that wasn't too difficult to work out!

VNA's are super cheap now and anyone with the remotest interest in anything RF should buy one.

Str.

Rob.:
I've been playing with my NanoVNA and all my HT antennas (close to 50 of them). Many, even some brand name stock antennas, are not resonant where they should be. I did testing in "free space" and close to my head as it would be in normal use. Many are designed to be resonant next to your head, btw.

I took a few of the cheap Chinese knock off antennas that I picked up for 10 for $10 and most were way off. Using a heat gun I removed the top plastic cap and started trimming the whip. In almost all cases the whip was too long and the 2m antennas were resonating in the 138-142 MHz range. After trimming performance was equivalent to other whips of comparable length.

Since a $1 antenna can be made to perform as well as a $15-20 one using the NanoVNA, I am quickly recouping my investment in this test device. 😁

NJQA:
KX4O works as an antenna engineer.  You may find his comments helpful.

https://www.hamradio.me/antennas/ht-antenna-comparisons.html

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