This article is coming by way of SonOfThunder, who’s just started up a blog of his own, the Sons Of Thunder Signal Corps Ministry. I like what he’s doing and even more so that he’s stepped up to the plate.
Some people think CB radio has gone the way of 8-track tapes. Nothing could be further from the truth! The Citizen’s Band Radio Service is as viable today as it was in its heyday during the ’70’s and 80’s. In technical terms, the 11 meter band (how radio operators may refer to it as the wavelength size is 11 meters) can work as skywave propagation as well as groundwave propagation. This means it has versatility in how it is used, as configured by the operator. While often seen as a rough and tumble domain of raucous truckers, hillbillies, and maybe some backwoods travelers, these characterizations really speak to its robust nature, ease of use, low cost, and accessibility.
Before this segment of radio frequencies were re-created by the FCC in 1945 as the Citizens Band Radio Service (C.B), they were in use by militaries around the world. One story I recall involves tank units under General Erwin Rommel’s command, the Desert Fox of the German and Italian North African Campaign during World War II. His tank units used the same frequencies that we now use in the C.B. (the radio then in German tanks was likely the FuG-5 which was considered a ground-wave only radio with a range of 2-3 km when using AM voice, the same modulation the C.B. service now uses; how wrong they were!). Unknown to him or his radio operators, these signals during the campaign were propagating by skywave, and were intercepted by Allied Forces. The transmissions were broadcast in the clear (meaning in plain language without any codes or effort to disguise their meaning) and the Allies used this phenomenon to their advantage.
The range of the C.B. radio like any radio, is determined by how it is transmitted and then how those transmitted radio waves interact with the environment. Even in the bottom of the valley where I live, my C.B. radio installed in my truck can reach farther than C.B.’s typically do. This isn’t by magic but by applying good antenna and radio theory to the configuration.
First of all is the antenna. It is probably the most important component of a C.B. radio as the actual radio technology is pretty standard, notwithstanding buying some suped-up rig or customized radio (this is a very simplified statement that will have to suffice for now). They all run 4 watts off the shelf but how efficiently and effectively those same 4 watts are used is determined by the antenna configuration. A tuned antenna is one which its length is trimmed (the installer literally can cut or adjust the length of the antenna) to a harmonic length of the radio’s frequency. Remember the alternate term for a C.B. is the 11 meter band? Well that’s the key bit of information that informs the size (length) of the antenna. The other determining factor is how big of an antenna one is willing to put on their vehicle or home. You might have the space to put up an 11 meter (36 feet!) long wire in your yard, but most people can’t, and it’s pretty impossible to put one on your vehicle and stay mobile. This serves as an example though of a full wavelength antenna: one that is exactly the length of the frequency wavelength. A (even) harmonic length is one that is divisible by an even denominator, e.g. 1/2, 1/4, 1/8, etc. A radio wave can be transmitted by an antenna that is an even harmonic (and some odd-harmonics, but don’t worry about that now). My truck has an antenna that is 4.5 feet tall. 4 and 1/2 feet is 54 inches. 11 meters is 433 inches. You divide 433 by 8 and you get 54, roughly. This is still a tall but doable length antenna for a pick-up truck. Some have done much bigger 1/4 wave antennas, referred to as a ‘whip’ because it’s a long 9 feet tall stiff steel wire. Cool, but you quickly start hitting things with your antenna and something, usually the antenna, begins to take a beating. To put a fine point on it, the Wilson 1000 magnetic mount C.B. antenna is as fine example of an antenna as reasonably can be obtained and is what I use. It’s easily tuned to 1/8 wavelength, and can take a beating and stay usable with minimal maintenance for years. Mine has.
So that’s it then, the secret is a tuned antenna, right? Not yet. The other component for this C.B. antenna we’re building is the ground plane. The ground plane is an electro-magnetic counter-poise to the vertical antenna. Luckily a pickup truck has one built in: the top of the cab or even camper. This metal ‘sheet’ acts as a ground plane to the antenna, increasing its effectiveness and efficiency. [We’ll have to leave the theory there to limit my brain strain.] When you have used your available resources to create the best antenna you can, then the radio, whatever model/brand you get can work at its optimum. Most C.B. radios on the market, and even the used market which is substantial, have a built in fine-adjustment for the antenna labeled “SWR” . This adjustment is easily accomplished by following the manual’s instructions, and puts the finishing touch on a good C.B. installation.
The actual C.B. radio you put in your vehicle can be a perplexing venture as there are as many makes and models as there are of just about anything else these days. To save time and get to a few good recommendations, I recommend Cobra C.B. radios and Uniden as those are what I have used. There are other good ones out there for sure, I just don’t have as much experience with them as I do the Cobra 29 LX or LTD, or the Uniden Bearcat 980SSB which is what I use in my truck now. The significant advantage of a “SSB” versus a non-SSB CB radio is the single side band simply takes common A.M. signal that all C.B. radios use and cuts it in half. Interestingly, you cut the A.M. signal in half and the 4 watts you have turn into 12 watts as your putting all that energy into a narrower signal. More power combined with an efficient antenna, and now you’ve got a longer range of usability.
So here is the long awaited gist of this article: the C.B. is a cost effective means to communicate over distances that are farther then typical when a little theory is applied to their configuration. I conservatively can hear/talk to almost anyone in my county which correlates to a 30 mile radius centered on my truck, and I live in a complex of mountains and valleys where the valley floor is around 1500 feet elevation and the immediate hill tops are at 4000 feet. Granted I don’t receive equally well in all directions due to the terrain, but it is remarkably better than one would expect. In flat terrain I imagine far better range.
C.B.’s don’t require licensing like Ham radios, are relatively inexpensive, and with a little theory can be installed to have a increased effective range. They run off a 12 volt DC battery, and can go just about anywhere your vehicle can go, the best part being it’s a way to talk while traveling. While not a reliable atmospheric condition, when the D-layer is active (see the “Rebirth of HF” article on this site) I get Superbowl traffic (the free-for-all channel 6) from Louisiana, here in the Pacific North West. No wonder the deserts of North Africa were no match for the active D-layer and the proto-c.b. radio!
As with any radio band (a contiguous segment of radio frequencies such as the FM Broadcast we all know, which runs from 88Mhz to 108 Mhz, or AM broadcast which runs from 500Khz to 1700Khz depending on the country you live in) there are advantages and disadvantages both in the nature of the radio waves and in the hardware used to transmit and receive them. The C.B. provides a robust, relatively low cost, accessible technology that can create connectivity in a community that doesn’t depend on outside technology or agencies. This can facilitate the local church in serving its members both in regular pastoral care as well as in emergent and disaster scenarios. It’s a tool to unify the Body of Christ and to serve Him.
18 thoughts on “The Venerable and Infamous CB Radio, by SonOfThunder”
The best analogies I have for antenna tuning and ground planes is using light. Tuning the antenna is like picking a colored globe for a candle. There aren’t any clear globes (except maybe discones) so you have to pick a globe whose color matches the thing you are trying to light up. The better the match, the better you can see the thing. If your thing is red, and you are trying to light it up with a green globe, it will look black. If you pick the right shade of red, it will light up brighter than anything else.
In this analogy, the ground plane is the mirror you put behind the candle.
That’s actually the same one I use in class. It really sinks in when you start explaining how Yagis and directional antennas work.
Yup. And when you get really down into directional antennas, it’s not lenses, it’s curved reflectors. ‘It’s all about the ground elements’ doesn’t just apply to warfare.
I got my first CB back in the early 70s, my call sign (yes the FCC had CB call signs!) was KAJB0961. Believe it or not, that call is still valid today. I’m now a Licensed Ham radio operator (since 2003). I bought my first Sideband CB in 1978, a J.C. Penny 6742. I buddy of mine worked his magic with his “golden screwdriver” and she was putting out 8 watts AM and 24 watts SSB. I had it in my work truck and we did a lot of work on the water on drilling rigs (loaded us on barges and towed us out). I would take the ground cables and hook one the barge and throw the other in the water, that made the perfect ground plane. I could talk all over the world then. I contacted Australia, Japan, Italy, Germany, even Russia! That was right in the middle of one of the biggest Solar Cycles ever. We are coming up on a new cycle number 25 soon. Fun starts again. BTW: The CB band (11 meters) used to belong to ham radio operators back in the 50’s
I have a CB radio in the Ham Shack with a large vertical base antenna. We are about 7 miles from the highway which is 2,000 feet in elevation below us.
I turn the CB Radio on primarily during big snow storms and listen to the truckers on Ch 19.. During a significant national or regional event, CB Radio could provide a lot of intel from truckers who are traveling through your AO from afar,
On SSB: a standard AM transmission has the carrier, and an upper AND lower sideband. When you suppress the carrier wave and one of the two sidebands, that’s where the “effective radiated power” gets that 3x multiple. 2/3 of the ERP that would have gone to carrier and the other sideband can get out and push the remaining sideband.
For just buying robust packages that come to us in boxes off the interweb, what is a good Cobra model and antenna combo for a vehicle? How about for a home base station, also assuming that the full height antenna is possible? While we can just click buttons and hit send, to grab another form of solid comms, we would be fools not to. And buy more mobile units “just because” for future contingencies. (Just like all them ChiCom Bowfangs we got. Misspelling intentional.)
And while you are at it, big solar panels that can charge golf cart batteries have never been better, or cheaper. They will keep all your gadgets and comms charged up, and they won’t give you away with a generator noise. There is no excuse not to have them, folks! No excuse! You need another AR? No, you need more comms and solar panels and deep cycle batteries for the long fight!
Quite good and quite simple- it rules the day brother. 😎
Currently running a uniden 980 ssb with a wilson 5000 in my truck. And a radio shack shack trc 495 with a antron 99 and ground plane 30 feet in the air for my base. This package has given me effective comms throughout my county without the use of repeaters or having to get a license. Solid article.
Matt et al;
Go here for a no frills, rock solid rig: Cobra 29 LTD
it will need to be wired into battery vs 12v adapter, so get some extra connectors and such:
12v power supply for home use: Power Supply
Antenna Options: https://amzn.to/3lYFden
75ah agm battery (i own and use this for my emcomm set ups)
Deep Cycle Battery
battery box for said battery to power radio and charge other devices via usb and plug into 12v socket ( i own this too)
Smart Battery Box
50w solar panel to charge battery (i own this one, amongst others) ipv6 rated
20A waterproof charge controller
With this set up, you got comms…add in a 25w https://baofengtech.com/product/uv-25×2/ for 2m/70cm/frs/gmrs/murs and general bubba scanning w appropriate antenna and you have a nifty little portable system… ( i own and use this in the field too)
I have the Uniden Bearcat 980 SSB as well, and a Wilson 1000 mag mount on the top of my truck (can’t really see it in the picture though). When the D-layer is active, I can do DX across the country, but even in my highly varied topography I can easily work my county or 50 mile plus radius from my truck when not in a valley or draw. The Cobra 29 LTD is a great CB. The only drawback is there is no SWR calibration, scanning, or sideband. These features allow one to fully use the CB band.
thank you for the insight. ham tech studying for general but looking for affordable options to augment comms for neighbors and others who haven’t been paying attention to the situation thats developing
That’s always a tough question. For myself, I decided to bite the bullet and bought an 8 pack of the Baofengs that were scheduled to be cancelled by the FCC. I plan to just hand them out (preprogrammed) to my neighbors in a part 97.403/405 situation.
But I have a CB too.
Since you are a tech, you have the basics already for neighborhood comms, your 2m/70cm rig and or rig modified to operate on frs/gmrs/murs bands, which they would use..
my mobile base rig is a kenwood tm-v71, same in suv, both have been modified.
If you can convince them to buy a basic uv5r or similar rig, then you have comms with them and they don’t have to be licensed…
I bought a stash of uv5rs to keep on hand to hand out, pre programmed, to worthy neighbors if need be and have gotten my mag group mates to obtain uv-82’s and helped them get set up and trained.
From my QTH, with mobile and j pole in attic, totally covert rig, i have the ability to cover my entire immediate AO via simplex, and can hit repeaters 100+ miles away, MT Mitchell being the easiest to hit..
YOu should look into GMRS repeaters and licensing too…money well spent to get entire family emergency comms…
Whats the goal? IMO, to spin up tac/local/neighborhood comms as simply and inexpensively as possible, this does it for me, ymmv…
Pingback: A CB Shopping List, by Henry Bowman – brushbeater
Reblogged this on Starvin Larry.
I’ve been using CB since 1976 and it always seemed crazy to me for the modern survival / prepper world to push Ham radio the whole time extolling its virtues of more power and range over the simplicity and availability of cheaper CB set-ups.
Luckily, wherever I’ve lived, there has been a local group using CB which left you knowing that when you call for help, that help is local and not miles away through a repeater.
Where I live now, there is a 4×4 recovery club and a couple of farms, all using CB.
In winter, they work closely with the police for transporting the sick and vulnerable when the roads are blocked to anything else. They also donated a base station CB set to the police (and set ii up for them) to keep in touch when the cell phone towers go down.
Except there is that range thing and power to deal with.
I’m also a UK freebander.
Apparently a bad boy in the eyes of radio hams as we aren’t licensed and don’t know what we are doing.
Yet using a 1/2 wave long wire plugged into the back of an all mode CB set, and using just 12 watts SSB, I regularly talk to Europe, the US, and beyond on voice and using a key.
The furthest regular contact? That would be Hong Kong. No, this isn’t a brag, just demonstrating that low cost, low tech, low power, doesn’t mean you are limited to short ranges.
Except I am minded to point out again that range doesn’t always translate to getting help quickly.
“May seem crazy” is not, at all. It’s a different tool for a different application, and it’s not even always good for the application suggested here. These days, depending on where you are it’s good for buying chickens from Illegals.
Competence, bandwidth, capability, are just three reasons off the top of my head. But this is not an amateur radio vs CB shitshow.
There’s always at least always one Fudd who steps out with a post on CB.
Comments are closed.