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Does this re-tuning procedure involve a hacksaw, by any chance?
Nope, just a couple of 7/16″ (pretty close to your 11 mm) wrenches!
How can I determine the optimal antenna length for my portable radio when I am listening at different frequencies?
Thanks,
Mike
Looks Great, Bob.
I am sure you won’t make the mistake I made by tuning an antenna _inside_ a quonset hut at high altitude (it was cold outside). After moving the antenna outside I realized it was too short, the metal roof impacted the VSWR quite a bit.
Always a pleasure, Bob.
Craig…
[Former Chief Engineer of Hawaii Public Radio]
To Mike L (about determining the optimal antenna length for his portable radio when listening to different frequencies:) Mike, as you know there is a direct mathematical relationship between the frequency, wavelength and the speed of light for all electromagnetic radiation (radio waves, light waves, x-rays) V=Fλ. Then you could figure out the speed of light in air, and use a correction for the diameter of your antenna conductor…. OR use an on-line calculator like this one: http://www.crompton.com/wa3dsp/hamradio/antcalc.html OR best yet, just try different lenghts to see which works best. At any frequencies in the FM band a quarter wavelength is anywhere from 26 to 32 inches in length.
To Craig: my garage is wood!