Topics For Technicians!
Not long ago I stumbled across a web page (by John Reisenauer. KL7JR) about using cb antennas on ham bands.I was very interested since I'm an over the road trucker and thought I'd give it a try.
I followed John's suggestions about antenna types and whip length. I started out with a Wilson FGT-3 antenna (3 footer) and a 40 and 3/4 inch whip. After some pruning I got the swr down to about 1:3:1 on 20 meters with the antenna mounted between my Tractor and trailer and made a few contacts with great signal reports contacts.
The 3 foot antenna was catching the tree limbs so replaced it with a Wilson FGT-2 and a 35 inch whip and it tuned down to a flat 1:1:1 swr on 20 meters. A few weeks ago I was in Tacoma, WA and threw my call sign out and a net control in Florida came back with, "That KC9 mobile go ahead." "Your about the loudest one out there". When I gave him my location he said, "Wow! I don't even have to turn my beams to hear you". You know that made me feel good since I'm only running a 100 watt Kenwood TS-50.
Since I replaced the 3 foot with the 2 foot antenna, I can very easily work 17 and 15 meters also. Before you buy an expensive mobile antenna, I encourage you to try these Wilson antennas. I don't make a dime from Wilson. I mention them simply because THEY WORK and also to help other hams with an inexpensive way to go mobile. I bought 2 Wilson FGT-2 antennas off Ebay for $16 apiece.
As John, KL7JR mentioned, start out with a metal clothes hanger for a whip and prune it down to get a good swr then cut a stainless steel whip the same length.
Wilson and other CB antennas in use on the ham bands.
Now, lets talk mobile antennas for a base antenna. WHAT did he say..??? That's what I said. While in Walcott, IA a few weeks ago I bought a $26 "Workman Electronics" 4 foot, 20 meter mobile antenna. When I got home this week I played with it and it just wouldn't tune down like the Wilson antennas so I took and idea I stole from KL7JR and made a base antenna out of it and I'm using it right now on my rooftop at home.
(In the test setup in above photo, I took the 4 foot Workman antenna with a 48 inch whip and screwed it into a 5 inch magnet mount and placed it on a large steel Pizza pan and tried to tune it with no luck. I remembered I had a ground plane kit for an Imax 2000 in my shed. As soon as I laid the radials out and let the threaded end touch the pizza pan... Bingo... Swr was 1:1:1 with R=55 and X=6. Beautiful numbers. I attached the radials to the Pizza pan with 12 gauge wire and the swr never changed. I sat the antenna on my roof and started using it with great results.)
CB antennas are cheap and fun to play with and they aslo WORK on ham bands......... Just see the article by John, KL7JR in the link at the first of this article. He's already done all the leg work and has all of the numbers. He's been doing it for years.
Note that a tuner may be required on many CB antennas that are used on ham bands.
Good luck and happy DXing.... Buddy KC9YYI.
You can email me for questions >> 1024truck (insert ATsymbol) gmail.com(no spaces)
Although this article is not meant to be a "construction" article it should give you some ideas to "roll your own" from inexpensive CB antennas for use on the ham bands.
If you are experimenting with CB antennas on the ham bands and want to share your fun with us and many thousands of other hams, just send an email to me, n4ujw at hamuniverse.com, and we will do our best to help share your fun with many others!
It's really easy to have YOUR results on the web and you get the credit! N4UJW