CB Radio performance

[uhfradarwill]

My line of work is in RF radar and communications and so I have access to a variety of RF test equipment.

I decided to test the cb radio output with a RF network analyzer to see just how much rf was radiated out of the antenna vs how much was reflected back to the transmitter.

I know there is a FM radio/CB interface box in the system so inherently there has to be some loss.

It turns out that on my bike 33% of the CB output is reflected back to the transmitter.

Not good at all.

Just sayin!!

[utadventure]

Will-

 

I have an '86 and having had CBs in vehicles since high school, I was not pleased with the performance of the CB when I purchased the bike in 2005. The sound and distance was not good at all. I put an SWR meter on it and it was horrible!

 

After some research, I learned about the Marshall Mod. It removes the OEM antennas, cable and especially the OEM splitter that allowed the factory set up to provide a single antenna for both the CB and the AM/FM.

 

I did the Mod and things were greatly improved. I removed the splitter, used the factory cable for the AM/FM and installed a Firestik antenna on the left side (from the rear). I also installed a Firestik antenna with adjustable tip in place of the original antenna, a new cable (18' I think) and was able to match the antenna to the CB within suggested range on both ends of the 40 channels. I've been happy with and regularly used the CB since.

 

I believe the splitter was the biggest of the CB issues.

 

Dave

[uhfradarwill]

Will-

 

I have an '86 and having had CBs in vehicles since high school, I was not pleased with the performance of the CB when I purchased the bike in 2005. The sound and distance was not good at all. I put an SWR meter on it and it was horrible!

 

After some research, I learned about the Marshall Mod. It removes the OEM antennas, cable and especially the OEM splitter that allowed the factory set up to provide a single antenna for both the CB and the AM/FM.

 

I did the Mod and things were greatly improved. I removed the splitter, used the factory cable for the AM/FM and installed a Firestik antenna on the left side (from the rear). I also installed a Firestik antenna with adjustable tip in place of the original antenna, a new cable (18' I think) and was able to match the antenna to the CB within suggested range on both ends of the 40 channels. I've been happy with and regularly used the CB since.

 

I believe the splitter was the biggest of the CB issues.

 

Dave

 

I remember the firesticks, great antennas indeed!! Yamaha makes great motorcycles but RF is a whole new ball game.

[Beachbum]

Will-

 

I have an '86 and having had CBs in vehicles since high school, I was not pleased with the performance of the CB when I purchased the bike in 2005. The sound and distance was not good at all. I put an SWR meter on it and it was horrible!

 

After some research, I learned about the Marshall Mod. It removes the OEM antennas, cable and especially the OEM splitter that allowed the factory set up to provide a single antenna for both the CB and the AM/FM.

 

I did the Mod and things were greatly improved. I removed the splitter, used the factory cable for the AM/FM and installed a Firestik antenna on the left side (from the rear). I also installed a Firestik antenna with adjustable tip in place of the original antenna, a new cable (18' I think) and was able to match the antenna to the CB within suggested range on both ends of the 40 channels. I've been happy with and regularly used the CB since.

 

I believe the splitter was the biggest of the CB issues.

 

Dave

 

I second this. On our Kenworth T-680s the factory setup uses a splitter and integrated cd/fm antennas. The coax, splitter, and lack of a solid ground result in high swr readings. My truck looks like it uses three antennas because I just leave the factory duals there for radio reception, and run an outback mount with a firestik and quality coax as my cb setup. It works so much better than factory. I’ll have to remember this if I ever feel froggy enough to mess with my venture cb