uhfradarwill Posted October 13, 2018 Share #1 Posted October 13, 2018 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!! Link to comment Share on other sites More sharing options...
utadventure Posted October 13, 2018 Share #2 Posted October 13, 2018 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 Link to comment Share on other sites More sharing options...
uhfradarwill Posted October 13, 2018 Author Share #3 Posted October 13, 2018 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. Link to comment Share on other sites More sharing options...
Beachbum Posted October 13, 2018 Share #4 Posted October 13, 2018 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 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now