May 8, 2017

Long Term Reliability of Equipment: Antennas

This is a Radio Shack VHF/UHF Scanner Ground Plane antenna that was installed about 2 1/2 years ago in central Wyoming.  Note the deterioration of the plastic insulation and rubber o-ring that isolates the center elements from the ground plane.  This antenna was only $20 from the local Radio Shack, and purchased as a stop-gap.  It served its purpose, but clearly was a short-term "fix" to get up and running.

This doesn't only happen with "cheap" gear.

This is a $230 Yaesu ATAS-25 portable field antenna that broke when being used at a Down-Grid Communications Class.  The failure point was a plastic screw used to attach the coil assembly to the slide contact/whip assembly.  Not what I expect out of a reputable brand that's priced accordingly, especially when its performance was no better than the significantly less expensive FARApole that FARA was selling at Hosstraders, or the (now discontinued) B&W AP-10 apartment dweller antenna that cost half as much.  Not that short portable HF whip antennas are great performers to begin with.

Those HF operators looking for small, portable, potentially covert antennas would be better off acquiring the skills to roll their own antennas. The best book I've found is the old TAB How To Build Hidden Limited-Space Antennas Antennas That Work, by Robert J. Traister, WB4KTC. It was published back in 1981, and is out of print, much like many good reference works. I found mine at a used bookstore for about a third of what they start asking for them on Amazon (the original new price was $9.95 in early 1980s money).  Here is a picture, and the Amazon link for it:

When you consider that an ATAS-25 costs $230, even the higher used prices of this book are significantly less.  Unlike buying an ATAS-25 that might break in the field, the knowledge in this book stays with you so you can make antennas when needed out of assorted raw materials you can find anywhere. Finally, the hardcopy meatspace book does not require electricity, an electronic appliance, or an Internet connection, and has information that has been vetted by a technically competent editor at what was one of the premier technical publishing houses.

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