I have a 2022 Volvo VNL760 with the stock CB antennas. I was just wondering if I'd gain much by getting different antennas. I have a Cobra 29LTD Classic radio. All that said, I seldom use my CB. But, on 2 lane highways and during inclement weather I do use it. I use it on 2 lane highways in case someone creeps up on me and needs to get around me. Try to coordinate with them on leap frogging them around me so they can be on their way without being stuck behind me. During inclement weather to hear any road conditions, etc.
But, not really into being on the CB jack jawing and the like. It is an important tool at certain times. I'm just curious if those stock antennas are adequate and not worth the (up to a) couple hundred bucks it may cost to replace with better ones or if it wouldn't gain me enough performance to be worth the bother. I simply don't know.
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Last edited: Mar 26, 2022
A co-phased dual antenna system.
It's the worst garbage in the Galaxy.
You may need to change the antenna and the original coaxial cable.
If there is a single antenna configuration
(one antenna feeds the CB Radio and the other one feeds the radio/satellite),
identify which antenna goes to the CB Radio
and check the SWR using an external SWR reader.
If the reflected signal is 1.1-1.5, but no more than 2,
leave it alone and use the RAMI original antenna.
If you have more questions,
there a lot of knowledgeable posters around here.
Just come back and ask.Neverready Thanks this.
1. I'm pretty sure, but not positive, that my antennas are both for CB and not satellite radio? Probably a simple T connection hooks them both together. Since I'm a company driver, probably not a great idea to go rummaging through the wires to determine how and where they are T'ed together. There's a couple of our garages where I know the mechanics and I'll probably ask them about it next time I have a chance. They may not know, but they may.
2. As for my SWR, my Cobra has both a built in meter, an SWR adjuster knob and a procedure to measure and adjust the SWR.. Much nicer than back in the 70's when you had to use a tiny Allen wrench to lengthen or shorten the physical antenna length to adjust the SWR. According to the built in gauge, my SWR is under 1.5, but hard to distinguish how much. That said, unsure if I should purchase a separate SWR meter and go that route. Although if I used an external SWR meter, unsure if the built in SWR adjustment procedure would still be valid and if not, how I'd adjust it. My thinking, based on my understanding of SWR (I do understand it probably better than many as I was an electronics technician and did deal with rf stuff. But, I admit I do not have a through understanding, only a general one about the theory regarding SWR, what it is and why it's important. My rf experience was for receiving, not broadcasting), is that the existing built in procedure to adjust SWR would probably still work the same. These antenna don't have the little allen wrench adjustment found on antennas in days of yore.
In your truck Operator manual you'll find a section called Communication and Entertainment.
You have a detailed description of your radio and the antenna system.
Look for the word 'multiplexer'. If this word is found, then you have a co-phased system, where both antennas are connected in parallel. If not they'll tell you which antenna is connected to the CB Radio,
Use only an external SWR meter, for a precise SWR testing.
Any truck stop sells one for about 30-35 USD.
You will need a short (1foot) coaxial cable too, for a connection to the transceiver output.
Follow the Astatic manual testing description.
The Astatic readings will be accurate and you should trust only those readings.
Let us know.
Good luck.Six9GS Thanks this.
The meters built into the radio are not always accurate, As previous poster pointed out use a external swr meter for a more realistic reading. You still may need to adjust antenna length to properly set SWR. Typically they are manufactured slightly longer than desired frequency range so you can dial it in. A single antenna system is easier to set.
In my experience with Volvo stock antenna systems, they don't work half bad with a stock CB like the Cobra 29. If the system is not messed up you will usually see a pretty good SWR reading. If it works for your needs, then stay with them. If you want to try a bigger, better antenna DON'T use the stock antenna mounts! They don't hold up very well. Driver's side antenna is for CB. Passenger side is for AM/FM radio.
Start with a pair of skipshooter. 2nd find a cb shop that has an antenna analyzer ..Or if you wanna learn,buy your own..either way you want #'s close to these except in 75 ohm vs 50
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