CB Radio Range in the Seneca

[Rick-in-Houston]

Just installed the Cobra 75WXST cb radio and a multiplex box for splitting am/fm and cb radio using the existing Seneca antenna.
Was wondering what kind of range you guys are getting on the open road?

[Sundancer330]

Lots of variables come into play with cb radio range, average range is 2-9 miles.

[dg1971]

Rick, in my opinion as well as remembering what I knew about cb radios from the 70's, I think you will be disappointed in the performance of the radio using a non-cb radio antenna, except in the case that you are "convoying" with someone else and traveling within a hundred feet or less of them. While you may be able to receive signals a couple miles away or more, your transmit range will be severly limited. Placing a 18" to 24" no ground plane dedicated cb antenna on top or even on the rear view mirror will make a big difference.

[SSGCharlie]

dg what is a no ground plane antenna?


SSGCharlie

[dg1971]

Charlie, its an antenna, usually made out of fiberglass that will transmit a signal from atop a vehicle such as an RV or an 18 wheeler with a fiberglass structure. A steel car, truck, etc. needs a regular grounded antenna to work correctly. That's about all I can offer in terms of an explanation. The below is from an ad for a No Ground Plane antenna.

The Everhardt NGP Mirror Mount Kit - 4'
$43.95
•A great option for mounting an antenna to a non-metallic surface
•Three-way mount attaches vertically or horizontally
•Requires virtually no need for tuning

[dg1971]

I should add that a NGP antenna will work on a steel vehicle OK but a regular ground antenna will not work correctly on a fiberglass vehicle.

[SSGCharlie]

dg Thank you for your reply



SSGCharlie

[Dustdevil]

Range has to do with antenna effective length, height above ground, and the ground plane underneath it. The actual ground is a good plane, but an antenna that close to the ground won't reach very far around the curvature of the earth. CB signals don't travel well through mountains or buildings either. So, the higher you can mount it the better for range. But if you just place it on top of a fiberglass structure, you lose the ground plane, and have to create one. A steel car body works well, but fiberglass does not. So, you have to use an antenna which is engineered to work well without a significant ground plane. I don't know what makes that different, but tuning the antenna is by far the most important factor in radio clarity and range.

[Bassdogs]

For practical purposes, CB range from a vehicle is 2 - 4 miles and often less. CB signal is "line of site" meaning you are not going to transmit thru a mountain or in an urban area with a lot of tall buildings. On the open interstate in Kansas [flat for hundreds of miles] you will get better range but a CB is limited in transmitting power so I'll stick to my 2 - 4 miles.

If you're travelling with a group of vehicles, you will be fine as long as you stay with in these distances. Unless you are wanting to listen to truck traffic to be alerted to road conditions ahead, you might be better served with the FMS handheld radios. You can get a pair of them for around $30 and you won't have to listen to a bunch of bad language.

[Rick-in-Houston]

Dustdevil, do you have a CB in your Seneca and if so what type of antenna are you using?

[Rick-in-Houston]

I'm just wondering if I should purchase a non-groundplane antenna for use on fiberglass structures. Would that help being mounted on the mirror?

[Dustdevil]

Originally Posted by Rick-in-Houston

Dustdevil, do you have a CB in your Seneca and if so what type of antenna are you using?

Rick, I haven't installed one in the Seneca at this point. Might later. I have one in the Jeep, which is valuable for 4 wheeling with other Jeeps. Those guys all have them. The ground plane for the Jeep antenna is the steel Jeep body, not my fiberglass top. Although, the fiberglass might provide a little bit of ground plane, it's not really what influences most of the power of the antenna.

If I decide to add mounting later, I can use the same radio, since it's on a quick disconnect in the Jeep. There are times I can receive from quite a distance on the Jeep CB, but it's not reliable. And transmit is much shorter distance than receive. If I do add antenna to the Seneca, I'll do one with no need for ground plane up on the roof, attached likely with a bracket along the side of the box so I can avoid putting holes in the rubber roof material. If I did that, it would likely also have a 2m/70cm antenna for my handheld HAM radio. I sometimes carry that in the Jeep for offroad trips to the backcountry, but have never had to use it.

[Dustdevil]

BTW, my CB antenna on the Jeep is a 48" Firestik. I'll also add a 2m/70cm antenna to the opposite side for the HAM.

[Robbbyr]

Originally Posted by Rick-in-Houston

Just installed the Cobra 75WXST cb radio and a multiplex box for splitting am/fm and cb radio using the existing Seneca antenna.
Was wondering what kind of range you guys are getting on the open road?

You mention installing a multiplex box, does your Seneca not already have one behind the dash? My 2014 does, but the CB connector on it is unused until one installs a radio and connects to the box.

If you installed your own multiplex box to the dash radio's antenna feed, could the factory multiplex box (if equipped on 2017s) be filtering out the frequencies you need to Tx and Rx?

[Rick-in-Houston]

Hey Rob,
I'm convinced my 2017 did not have a multiplex after tearing the dash apart and tracing the am/fm coax from the radio to the firewall.
Contacted Freightliner and the confirmed it does not. So I put one in and ran a new coax to the am/fm radio.

[Robbbyr]

Originally Posted by Rick-in-Houston

Hey Rob,
I'm convinced my 2017 did not have a multiplex after tearing the dash apart and tracing the am/fm coax from the radio to the firewall.
Contacted Freightliner and the confirmed it does not. So I put one in and ran a new coax to the am/fm radio.

Makes me now wonder if the antenna is capable of CB and AM/FM operations or whether Jayco/Freightliner cut that out like they did the Overdrive cancel switch?

[Rick-in-Houston]

Me too...jury is still out on the antenna. Have not had the Seneca out on the open road since the install. Concerned how effective the antenna is.

[Krz]

2014 Jayco Seneca.....used a splitter to connect my radio and CB to same antenna. No success. CB could not pick up anything on our trip last year.


I just installed an antenna on my passenger mirror (just like the factory driver side mirror) and ran a dedicated cable to my CB. So leaving for a trip in a few weeks and will post how it worked.

[fiorilsa]

Rick, I added a Firestik NGP antenna and it works a lot better than the antenna on the drivers side. Hard to tell the distance but if I had to guess, I would say I can receive anywhere within a mile or so. I ran a dedicated line to the overhead console area and that is where I have the CB mounted.

[Rick-in-Houston]

Thanks fiorilsa for your response.