Your foreign license plate number?

For any amateur band above 20m this is the easiest solution in the field, a 5 meter whip antenna with a magnetic suction mount on the trunk of your car, it results in a SWR of 1.6 and you can tune it to anything above 20m by simply shortening the whip. MFJ makes these, the MFJ 1979 is the whip and the MFJ 336T is their magnetic suction mount. I haven’t tried this on the roof yet since I’m slightly worried about the thickness and the lack of anything that provides more stiffness. After posting these images on facebook the first reaction of my cousin was, are you now also carrying foreign license plate numbers? I rest my case about opinions in our country.

image1
The MFJ 1979 and their 336T on the trunk of my car
image2
The analyzer shows a SWR of 1.63, so that appears to be fine
fieldday16032017
16-Mar-2017, a field afternoon, the FT-991 was able to tune the whip between 14250 and 14350 kHz, I’m deliberating about a solution to move it more center 20m band.
Fieldday on March the 19th, notice the tuning stub at the end of the whip. Also, what you don’t see is that I added several radials to the magnetic suction mount. 3 radials of 10 meter each did the job.
It turns out that a 25cm tuning stub centers the resonance frequency in the 20m band.

 

Last update: 17-mar-2017

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2 thoughts on “Your foreign license plate number?

    1. I added a tuning stub of 25 cm and it brings the resonant frequency down to the center of the 20m band, going now to the field to test this. Photo of the 19th of March added to the blog

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