SWR reading

Quoting from http://www.rightchannelradios.com/pages/cb-antenna-tuning-guide-pv-c0-61.html

"The objective behind tuning your antenna is to make these two readings as close as possible. Getting down to a 1.5:1 ratio or below makes for a passable broadcast signal. There are two basic points to understand before adjusting the length of your antenna:

If the SWR on channel 40 is higher than that on channel 1, your antenna is too long.

If the SWR on channel 1 is higher than that on channel 40, your antenna is too short.



If your antenna is too long, it is necessary to reduce its physical length. There are several methods for shortening an antenna which vary by manufacturer. Consult your owner’s manual for detailed instructions on how to shorten your antenna. While many antennas feature a “tunable tip” that makes use of a small screw, some antennas may need to be cut to be shortened. Do so in 1/4 “ increments and then get new readings to determine your progress.

If your antenna is too short, it is necessary to increase its physical length. Most instances where the length of an antenna is too short are caused by a lack of ground plane. In modern antennas, there is usually a method for adding length built into the antenna. Other options, such as adding a spring, are also legitimate options."

Leon
(kc0iv)

 

where is the antenna mounted on the pickup truck and what type / kind of antenna is it?

 

My thoughts exactly. Need all the info to be of any real help. Example: I have a 2000 GMC Sonoma. I could not get a decent SWR reading on the bed anywhere. Even ran a braid strap from the bed to the frame. (only one though, probably should have used four. Also didn't try a braid strap from bed to cab, thought of it later and still suspect it might have solved the problem.) Ended up mounting the antenna on the left front fender across from the am/fm antenna. (wilson 1000 roof mount on a SS bracket I made) Had excellent SWR. Didn't like the looks and finally did it right and mounted it in the center of the roof (it's the best location hands down.)

 

I guess I had better move my 48" antenna even though the VSWR is 1:1.05 at chan 20.

Mine is mounted 6" from the front corner on the side rail.

I also have 2 meter antenna on the other side mounted 6" on the right corner. It also has a low VSWR but I don't recall what it is.

Leon
(kc0iv)

 

You need more groundplane at 10 or 11 meters. I run a 2 meter 5/8 wave on one side and a 10 meter FM wip on the other side of my corolla's trunk.

Since I swap the FM ant for a CB antenna It shows up when you try to match them while the 2 meter ant could care less.....

Like buying a house LOCATION..... LOCATION

 

That's interesting. I had my 102 whip mounted on the bulkhead of the bed on my truck and I never had any SWR issues. A foot of said antenna was obscured by the upper cab, which was more glass than metal. I had 1.2:1-1.4:1 SWR's on all of my 4 watt radios and a 1.7:1 on my 10 watt radio.

Now mounting it on the bed floor probably would have been an issue.

 

Yep An't antennas fun

 

Well Bruce that CB antenna has been used for about 10 years and it works fine.

In the city about 3 miles is the best it will do. Away from the city I have no problem talking 5-10 miles during the day and farther at night.

Think about it for a moment. The roof isn't anywhere as large as the bed. That is on a full size pickup.

Leon
(kc0iv)