CB vs. GMRS/FRS

[Mainspring]

I am brand new to this and just got my GMRS license this week. I have not used a CB radio since the 70s, but considering the range of CB vs FRS, or better, GMRS, what is the advantage of the latter over the former?

Second question, are there radios that combine CB with FRS/GMRS capabilities or are the two just so separate animals that they are never combined into one unit?

As a side note, one reason I ask about CBs is that I just drug out two Cobra 19 Plus radios from 1986. They appear to be in excellent shape but transmission/reception is yet to be proven. I'll try and test them tomorrow.

Thanks for your discussion.

Danny

[BoxCar]

GMRS is short range, line-of-sight communications but has a higher power output than CB. GMRS is also FM where CB is AM so the messages are much clearer. GMRS is able to use repeaters that improve the range and can be connected to form networks. Because the frequencies for CB are around 27 MHz and GMRS is in the 460 MHz area the two can't be combined into a single unit.

[MichaelLAX]

3 hours ago, BoxCar said:

Because the frequencies for CB are around 27 MHz and GMRS is in the 460 MHz area the two can't be combined into a single unit.

Oh dear: someone forgot to tell that to Yaesu! 

 

[BoxCar]

3 hours ago, MichaelLAX said:

Oh dear: someone forgot to tell that to Yaesu! 

 

 

Yes Michael, there are units that do cover those frequencies but Mr. KIA, the OP was asking as a person not licensed to operate that type of unit and specifically for a unit to cover just the GMRS and CB bands which there isn't a unit. So, quit being an idiot and address the question being asked in the frame it was asked. And further, the Yaesu doesn't operate on the GMRS or CB frequencies without illegal modification so the answer is STILL there isn't a unit that combines those particular frequencies.

[Mainspring]

9 hours ago, BoxCar said:

GMRS is short range, line-of-sight communications but has a higher power output than CB. GMRS is also FM where CB is AM so the messages are much clearer. GMRS is able to use repeaters that improve the range and can be connected to form networks. Because the frequencies for CB are around 27 MHz and GMRS is in the 460 MHz area the two can't be combined into a single unit.

Thank you, sir! Much appreciated.

[mbrun]

I am brand new to this and just got my GMRS license this week. I have not used a CB radio since the 70s, but considering the range of CB vs FRS, or better, GMRS, what is the advantage of the latter over the former?
Second question, are there radios that combine CB with FRS/GMRS capabilities or are the two just so separate animals that they are never combined into one unit?
As a side note, one reason I ask about CBs is that I just drug out two Cobra 19 Plus radios from 1986. They appear to be in excellent shape but transmission/reception is yet to be proven. I'll try and test them tomorrow.
Thanks for your discussion.
Danny

Welcome to myGRMS.

From a portability standpoint, the FRS & GMRS radios are smaller than the CD handhelds have historically been. And because they operate in the UHF band their antennas are naturally much smaller.

FRS and GMRS both use FM modulation which means that atmospheric static is not introduced into the audio. CB(CBRS) using AM, USB, LSB. FM has recently been approved by the FCC for use in the CBRS, so in time that difference will become moot.

FRS and GMRS hardware supports squelch codes (CTCSS & DCS) that give you and your group the ability to prevent the squelch on your radios from opening except when a transmitter using that code transmits. So if you are on a camping trip and your family all uses CTCSS 67.0, you will only hear radios that use that code.

FRS and GMRS are not subjected to the gross degree of daily signal propagation changes that affect your range and the ability to communicate locally as CB is. Don’t expect skip to suddenly permit you to talk to Texas from New York because of temporarily atmospheric condition change. But you may experience conditions were perhaps you can talk another town or two away.

FRS and GMRS radios can mostly interoperate because they share 22 or 30 frequencies in common.

GMRS radios are permitted to use wide-band modulation, which can give some GMRS radios an audio quality advantage over FRS. FRS is limited to narrow-band modulation.

GMRS requires a FCC license whereas CBRS and FRS do not.

The GMRS service permits use of radios up to 50 watts. FRS maxes out at 2 and CBRS maxes out at 4.

The GMRS allows for the use of repeaters. Repeaters make it to possible to increase the usable coverage range, most notably when the repeater is installed in a prime high location. It is not uncommon to have repeaters that cover an entire City, even some that will make it possible for two handhelds 40 miles and more apart to communicate.

A GMRS license gives you the permission you need to put up and operate your own repeater.

Antennas for GMRS do not have the 20’ above building or tree rule that the CBRS is subjected to. Instead, height limit rules are the same as for Cell Towers, TV Towers and other tall structures where the FAA rules dominate. If you can afford to put up a 200’ tower and get approved to do so from your local AHJ you can put it up.

Regarding hardware. FCC rules require the use of part 95 certified hardware for CBRS, FRS and GMRS. Each service has its own set of technical certification criteria. I know of no equipment that is dual-service certified. This does not mean there is not hardware that can be modified to operate on two or more services, just that doing so violates your authority to use it. Many, including some members of this forum, choose to operate outside the rules.

Hopefully this information is useful.

Regards, and again, welcome to myGMRS.


Michael
WRHS965
KE8PLM

[MichaelLAX]

6 hours ago, BoxCar said:

So, quit being an idiot and address the question being asked in the frame it was asked...

Refresh my memory: 

Did you suggest that a radio containing both the CB and GMRS bands is not commercially available; 

Or, did you suggest that:

Quote

Because the frequencies for CB are around 27 MHz and GMRS is in the 460 MHz area the two can't be combined into a single unit. (emphasis added)

If you were more careful with your statements, you would not have to needlessly hurl insults when someone wants to set the record straight...

 

[BoxCar]

Michael,

Kindly show the world where there is an approved device that covers both the GMRS and CB frequencies and not a unit that covers frequencies outside those two bands.

[Mainspring]

4 hours ago, mbrun said:

Hopefully this information is useful.

Marvelous explanation! Thank you very much.

[MichaelLAX]

15 hours ago, Mainspring said:

Second question, are there radios that combine CB with FRS/GMRS capabilities or are the two just so separate animals that they are never combined into one unit?

Danny: While technologically feasible (but perhaps commercial not feasible), current FCC Part 95 regulations are generally interpreted to not allow certification for a GMRS device that can also transmit outside the GMRS channels.

This topic comes up quite frequently about why GMRS devices do not include the license free MURS channels.

[kidphc]

Having a units (separate) that does 11m (cb) and gmrs.

The gmrs with repeaters and such function with much more fidelity because of the use of fm.

The cb can reach out further at times, but not due to power, but propagation openings and use of ssb mode.

I much prefer gmrs because of how clean it sounds versus cb at the limits. Although, relatively close the cb can be pretty clear.

Still waiting for cb radios that can do the newly approved fm. Yes, my rig can do fm for cb, probably will be to wide banded (not even sure what the bandwidth is).

Kinda like comparing a pencil to an eraser. Now talk about user base, usually much more discipline on actual licensed gmrs users, frs toy radios can be intresting. Cb radio, well you have to get on it to understand.

Sent from my SM-G975U using Tapatalk

[PACNWComms]

A few months ago, I made a trip to a friend's place in Montana, and equipped my new car with a magnet mount CB antenna/Cobra 75 WX ST, and a Radioddity DB20-G VHF/UHF radio. I knew that many long haul truckers still have Cobra 29 LTD Classic CB's in their tractor's, from the factory in many cases. These are still used, as they were in the 1970's a la "Convoy" to talk amongst themselves and others. As mentioned above CB is 5 watts, AM and 27MHz (-ish). GMRS is FM, higher power and UHF band, and with the cost of radios coming down, becoming much more popular. I used both as I knew that there is a different demographic using each, and spoke with both on my trip. The reason for my trip, to help install a Yaesu FT-991A HF/VHF/UHF radio base station, and appropriate antenna to allow for Wireless Message Terminal (WMT) software for email and instant messaging between sites in Idaho and Montana. Even now in 2022, there is a need for both, and more. 

One issue that did come up though was the term "citizen's band" as all of us were world travelers, and, outside of the United States, many countries use 27MHz/FM or (450-470MHz) UHF/FM for their citizen's band radio systems. At one point someone handed me a Uniden FRS radio when I said I would try to talk to them via CB, when I meant 27MHz AM Cobra CB, not Uniden FM/UHF CB.

[OldRadioGuy]

Maybe I missed it but I don't think anybody mentioned SSB CB radio.  SSB is 4x(?) more efficient than AM and also uses much less bandwidth so lower noise - if the filters are done right.  It is still a form of amplitude modulation so there is more static than FM.  But AM fades more gracefully than FM which tends to be "all or nothing". Sometimes on AM you can make out a very weak signal that would not be captured by FM.

The longer wavelength will handle terrain better but the antenna also needs to be much longer.  It's pretty hard to put a number on all the differences.

Vince

[kidphc]

Maybe I missed it but I don't think anybody mentioned SSB CB radio.  SSB is 4x(?) more efficient than AM and also uses much less bandwidth so lower noise - if the filters are done right.  It is still a form of amplitude modulation so there is more static than FM.  But AM fades more gracefully than FM which tends to be "all or nothing". Sometimes on AM you can make out a very weak signal that would not be captured by FM.
The longer wavelength will handle terrain better but the antenna also needs to be much longer.  It's pretty hard to put a number on all the differences.
Vince

I love ssb on cb. Well except everyone being off tune (never used the clarify so much, personally it seams like they do it so they can be heard) and talking over each other.



Sent from my SM-G975U using Tapatalk

[CudjoeCane]

Well, my CB gear, whether it is AM, SSB or FM isn't going anywhere.  I find CB is still better for roadtrips.  Locally (SE Florida) , however, GMRS has really taken off. So I've got both a CB and a GMRS radio at home, in the cars and in the boat. 

[marcspaz]

I love this subject.  Mostly because I like both for different reasons and because of the responses I get to what I am about to type... Hopefully I don't catch too much grief for writing an unsolicited novel.  LOL

 

Bottom line is, on a peer to peer level, if a CB (HF) radio is properly installed and has a proper antenna and antenna installation, CB radio (HF radio as a technology) absolutely destroys GMRS in overall performance.

CB provides great line of site coverage; the same coverage as GMRS, but also provides ground wave propagation, sky wave propagation and weaker signal receive capability.  Combined, those propagation methods make CB a much better platform.  I dare say far superior segment of the Personal Radio Service, due to having coverage inside of potentially 1,200 to 2,400 mile radius, depending on the propagation models used and atmospheric conditions available at any given moment. 

A GMRS radio, in a standalone configuration like CB radio, will never be able to compete with CB.  Sure, there are very limited conditions that occur throughout the year and solar cycles that allow GMRS radios to cover anywhere from 300 to 600 miles, but they are extremely rare and can't be counted on for day to day use.  Reality is, 99.999% of the time, you are bound to RF Line of Sight.  Depending on where you are, that can be less than 1 mile or as much as 150+ miles.  It just depends on your elevation and the elevation of the other station.

Now... that opinion is supported solely on the precedent that the CB radio and antenna are of proper quality and installed correctly.  The biggest problem that has led many to believe the CB is not good, is the overwhelming amount of trash radios and short antennas on the market, combined with almost never having the system properly installed.  Enter GMRS.

Again, just my opinion... people getting frustrated with supposed poor performance of CB, pushed a large segment of the 'license by rule' users to look for another option.  With GMRS being on the bottom-end of UHF, the antenna installation is significantly less temperamental, making it so you almost have to try to do a bad install.  Combine that with the point that the market has some quality radios that can be purchased easily and for a reasonable price, plus FM sounds more pleasant to listen too, and now people start flocking to FRS and GMRS.  For more advanced users, GMRS wins over FRS due to the higher power available, the mobile and base station capability (removing dependencies on AA and AAA batteries and improved range) and the fact that we have networked repeaters available in many locations, and now the masses move to GMRS.

In my opinion, is GMRS 'better' than CB?  No, but it sure is a lot of fun and provides a much easier platform that fills the need to a larger group of non-technically skilled people, making it better choice than CB for many.  And that is an important distinction.

[Lscott]

37 minutes ago, marcspaz said:

I love this subject.  Mostly because I like both for different reasons and because of the responses I get to what I am about to type...

If one wants to think about it a bit differently 11M CB is a license free simple HF service. That goes with the license free MURS and FRS services too. For someone who doesn't want to deal with tests and licenses but wants to sample the RF waters the above is about the easiest and cheapest way to get a taste of the radio hobby and the differences between the bands. Part 95 services has HF, VHF and UHF bands to buy radios for and have fun. CB 11M radio has it's place. 

[WRPL700]

On 7/18/2023 at 11:08 AM, marcspaz said:

I love this subject.  Mostly because I like both for different reasons and because of the responses I get to what I am about to type... Hopefully I don't catch too much grief for writing an unsolicited novel.  LOL

 

Bottom line is, on a peer to peer level, if a CB (HF) radio is properly installed and has a proper antenna and antenna installation, CB radio (HF radio as a technology) absolutely destroys GMRS in overall performance.

CB provides great line of site coverage; the same coverage as GMRS, but also provides ground wave propagation, sky wave propagation and weaker signal receive capability.  Combined, those propagation methods make CB a much better platform.  I dare say far superior segment of the Personal Radio Service, due to having coverage inside of potentially 1,200 to 2,400 mile radius, depending on the propagation models used and atmospheric conditions available at any given moment. 

A GMRS radio, in a standalone configuration like CB radio, will never be able to compete with CB.  Sure, there are very limited conditions that occur throughout the year and solar cycles that allow GMRS radios to cover anywhere from 300 to 600 miles, but they are extremely rare and can't be counted on for day to day use.  Reality is, 99.999% of the time, you are bound to RF Line of Sight.  Depending on where you are, that can be less than 1 mile or as much as 150+ miles.  It just depends on your elevation and the elevation of the other station.

Now... that opinion is supported solely on the precedent that the CB radio and antenna are of proper quality and installed correctly.  The biggest problem that has led many to believe the CB is not good, is the overwhelming amount of trash radios and short antennas on the market, combined with almost never having the system properly installed.  Enter GMRS.

Again, just my opinion... people getting frustrated with supposed poor performance of CB, pushed a large segment of the 'license by rule' users to look for another option.  With GMRS being on the bottom-end of UHF, the antenna installation is significantly less temperamental, making it so you almost have to try to do a bad install.  Combine that with the point that the market has some quality radios that can be purchased easily and for a reasonable price, plus FM sounds more pleasant to listen too, and now people start flocking to FRS and GMRS.  For more advanced users, GMRS wins over FRS due to the higher power available, the mobile and base station capability (removing dependencies on AA and AAA batteries and improved range) and the fact that we have networked repeaters available in many locations, and now the masses move to GMRS.

In my opinion, is GMRS 'better' than CB?  No, but it sure is a lot of fun and provides a much easier platform that fills the need to a larger group of non-technically skilled people, making it better choice than CB for many.  And that is an important distinction.

Hi Marc:

I have been thinking about getting a CB (used to have one back in the 70s and 80s).  I see they have FM now and when I was browsing one CB shop they have SSB.  What format do you think would more consistantly get longer distant comms? 

I was a military radio operator for 12 years, and was told I should get my HAM license, but never did... unfortunately.

Thanks in advance.

 

[WRQI583]

On 12/31/2021 at 2:15 AM, MichaelLAX said:

Oh dear: someone forgot to tell that to Yaesu! 

 

 

I am pretty sure if they did make a CB/GMRS radio, it would not cost over a thousand dollars. I am also pretty sure that some people got into GMRS because they want to sell organs just to afford a radio. I hate being "that guy" but going out of band with a Ham Radio is illegal. 

[marcspaz]

2 hours ago, WRPL700 said:

Hi Marc:

I have been thinking about getting a CB (used to have one back in the 70s and 80s).  I see they have FM now and when I was browsing one CB shop they have SSB.  What format do you think would more consistantly get longer distant comms? 

I was a military radio operator for 12 years, and was told I should get my HAM license, but never did... unfortunately.

Thanks in advance.

 

 

 

Hi.. good questions. 

FM is a nice feature for CB and is capable of traveling thousands of miles.  Just a few days ago, I talked to a person in Texas on 4w FM and it sounded like he was right next to me.  However, SSB provides you both more power at 12.5w, and better weak signal recovery.  So, with all things being equal, SSB is a better way to go, if you find a radio you like and it only has one of those modulation options.  The majority of CB's on the market are only AM.  Some are AM and SSB. Some are AM and FM.  Very few are AM/FM/SSB, and they are a bit expensive.

 

[WRPL700]

2 hours ago, marcspaz said:

 

 

Hi.. good questions. 

FM is a nice feature for CB and is capable of traveling thousands of miles.  Just a few days ago, I talked to a person in Texas on 4w FM and it sounded like he was right next to me.  However, SSB provides you both more power at 12.5w, and better weak signal recovery.  So, with all things being equal, SSB is a better way to go, if you find a radio you like and it only has one of those modulation options.  The majority of CB's on the market are only AM.  Some are AM and SSB. Some are AM and FM.  Very few are AM/FM/SSB, and they are a bit expensive.

 

Marc:

Thanks again for the info.  I find myself drawn to the Galaxy DX-959B.  No FM, but AM/USB/LSB.  Any special antenna recommendations?  I would imagine they are all veritcal, not horizontal.  Antennas would have to be pretty important to such low wattage rigs.

[marcspaz]

10 hours ago, WRPL700 said:

Marc:

Thanks again for the info.  I find myself drawn to the Galaxy DX-959B.  No FM, but AM/USB/LSB.  Any special antenna recommendations?  I would imagine they are all veritcal, not horizontal.  Antennas would have to be pretty important to such low wattage rigs.

 

Love Galaxy radios.  They are fantastic. 

 

My best recommendation would be a true 1/4 wave antenna... I you're serious about it.  I ran a 104 inch steel whip antenna that was hard mounted to the body of the vehicle. I was using a Galaxy radio, myself.  There are some really nice antennas for base stations, too. Moonraker makes nice beams and vertical antennas.

 

The magic in every radio is the antenna. Depending on band conditions, you can talk 9,000-10,000 miles with 1/2 watt.

[WRQI583]

9 hours ago, WRXE944 said:

That guy: Ham Radio Outlet, as well as others, are happy, for an extra fee, to provide the “MARS/CAPS” mod to many of the radios they sell. 

“If you build it, they will come!”

I know I know ha ha........ Personally, I dont care if the radio goes out of band, I just know there are many guys on these sites that if you say a Ham Radio will do CB and FRS, they instantly turn into the human version of a nuclear bomb and start quoting the FCC rules and telling people how radios that go out of band is the whole reason that Ham Radio is going down the tubes. That's one of the reasons I dont get involved with people in the radio community. There are so many of those type of people around, I dont know who to trust. I'm just trying to enjoy radio, that's all.

[Guest]

6 minutes ago, WRQI583 said:

[...] I just know there are many guys on these sites that if you say a Ham Radio will do CB and FRS, they instantly turn into the human version of a nuclear bomb and start quoting the FCC rules [...]

In all fairness, that only happens if the topic claims something like: "Legal and certified HT that covers ham, GMRS, and your garage door remote..." or something like that. In most cases, the technical discussion about what is possible knows no limits 

6 minutes ago, WRQI583 said:

[...] telling people how radios that go out of band is the whole reason that Ham Radio is going down the tubes. [...]

... and I always thought because too many hams are arrogant snobs. 

73,

and don't get worked up because people disagree 

[Guest]

6 minutes ago, WRXE944 said:

If my GMRS HT can also make toast, is it still Part 95 certified!? 

 If you use IR radiation for the toast, you should be good. In case you use RF, like your microware, the question might be more complicated