The response and interest in my presentation was great! Here are the links from the presentation and the details of my antenna build. Remember, we’ll be building this antenna at the July 28th, 2018, Lecture and Lab.
My modifications to the design by F3WM:
If you want to reproduce my design exactly, use CQ-118 from The Wireman.
I wanted full 2-meter band coverage; I used a 19 11/16” (498mm) upper section and a 19 3/4” (500mm) lower section instead. His size will work better in a radome, if you want to weatherproof the antenna.
The pipe that I had was narrower than what he called for, so I used an on-line calculator at K7MEM.com to estimate the required size of a coil on a narrower pipe. My coil was 3/4” pipe, 3 inches long, with ¼-inch holes spaced 1 3/4” (42m) apart. There were 6 turns.
I omitted the end loop for hanging, and used an icicle hitch instead.
My links and references:
Anonymous
https://en.wikipedia.org/wiki/J-pole_antenna
Robert L. E. Billon, F3WM (The design I built and analyzed for the meeting.)
http://www.qsl.net/f3wm/radio/pocket.html
Frank Bremer, PA0FBK
http://www.qsl.net/pa0fbk/hampage_uk.htm
Joel R. Hallas, W1ZR
QST, March 2015, pg. 64
Joe Leggio WB2HOL
http://theleggios.net/wb2hol/projects/rdf/tape_bm.htm
Martin Meserve, K7MEM
http://k7mem.com/Ind_Coil_Ind_Calc.html
Charles T. Rauch, Jr., W8JI
https://www.w8ji.com/sleeve_baluns.htm
Al Yerger, K2ATY
QST, May 2014, pg. 45-47
And a bonus! The 2-meter vertical dipole I use at public service events:
Harold Melton, KV5R
http://kv5r.com/ham-radio/2-meter-sleeve-dipole/
[…] N8WWR, described improvising a coaxial vertical dipole when he needed an antenna that would fit through the tiny gap in a hotel room […]
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