I went camping last week in the RV and took along a radio. I was hoping to put up the coil loaded dipole I made, but the park ranger came around and told me I couldn't attach anything to trees after I got the rope up in it. It's a private campground, so you have to go by their rules. Well, I have a couple different portable HF antennas that I took along also, so I figured I could just unhook the CB antenna and mount those there. Here are a few pics of the simple station. You can see that I used the coax from the CB that runs under the chassis and just extended it over to the table. Sometimes I bring all the digital stuff, but not this time. It's not much to look at, but here it is:
I found out something interesting on this trip. I have the mobile CB antenna attached to the ladder on the rear of the coach and have the ladder grounded to the frame. SWR measured at the radio was about 1.5:1. When I decided to use this mount for the portable HF antennas on lower bands, I couldn't get the SWR under 2:1 regardless of which antenna I used. That told me something fishy was going on. I did some quick ghetto campground tests and found the problem: The ladder isn't providing enough path to ground. When I bypassed the ladder with the jumper cables, everything worked great. I guess on the 11m band the coax shield was also helping to provide enough counterpoise to make it present a low enough SWR to the radio, but that flaw was quickly exposed when I tried to go to lower bands. I bet the CB will work a lot better, too after I fix this permanently Here are some pics of the antenna install and the campground temporary fix:
I found out something interesting on this trip. I have the mobile CB antenna attached to the ladder on the rear of the coach and have the ladder grounded to the frame. SWR measured at the radio was about 1.5:1. When I decided to use this mount for the portable HF antennas on lower bands, I couldn't get the SWR under 2:1 regardless of which antenna I used. That told me something fishy was going on. I did some quick ghetto campground tests and found the problem: The ladder isn't providing enough path to ground. When I bypassed the ladder with the jumper cables, everything worked great. I guess on the 11m band the coax shield was also helping to provide enough counterpoise to make it present a low enough SWR to the radio, but that flaw was quickly exposed when I tried to go to lower bands. I bet the CB will work a lot better, too after I fix this permanently Here are some pics of the antenna install and the campground temporary fix: