Why is there NOT a VHF or UHF CB in America , and Why is CB not Digital ?

[Ensnared]

You have digital cb its called family service

No, I was specifically talking about 27.185 mhz. From what I am seeing from other posts, this might be too narrow to pull off. Thanks for your response.

 

[jbhunt04]

If there was a Digital CB , chances are it would not work very well after all of the golden screwdrivers Peeked and tweaked the radios . Digital is a much more narrow bandwidth than AM and they probably would just not work after being "Adjusted"

Seems as if that’s all the cb repair people do, is peaked and ruined...

 

[KK4JUG]

Seems as if that’s all the cb repair people do, is peaked and ruined...

And, that's why they get paid the big bucks. Money does not always yield quality.

 

[WB9YBM]

Hello to All. I know CB is near HF, and I know of FRS/GMRS but those are VHF Analog only, what About CB in the VHF/UHF Spectrum that is Digital.

I agree that much more can be done with conventional CB but has not (yet, at any rate) been made legal--certainly the technology exists whereby we could enjoy more communications mode on CB. Maybe it's the FCCs way of encouraging people to get their ham radio license where the other modes are legal to use.

 

[WB9YBM]

CB would be unusable if it were digital. No one would be able a get a word in. That's why aircraft typically uses AM.

I'm not sure being able to "get a word in" has anything to do with the mode of transmission, AM or otherwise.

 

[danesgs]

Or you could just get a HAM license and have more bands to play on.....Everyone is correct. Spectrum above 150 is money in the bank to the FCC. With all the new modes coming online for those folks that need discrete channels or modes (DMR comes to mind), the FCC does not want to play with freeband anything. CB at HF frequencies and 4 watts is about the only "free" spectrum that will get you any kind of distance but its still a wasteland of over-modulated signals. Cell phones and networks have replaced RF in the traditional sense. That is until a hurricane or other natural disaster takes the towers out.

digital signals at HF frequencies for voice traffic just really do not make any sense from a manufacturers standpoint for sales to consumers. Only exception would be VOIP but again you come back to Amateur radio and a very select group of users versus VHF/UHF bands. Suggest the OP download this and study it a bit.

https://www.ntia.doc.gov/files/ntia/publications/2003-allochrt.pdf

Not much land left to give away on this island earth.

 

[nd5y]

Your NTIA frequency allocation chart link is from 2003. The current one is at

United States Frequency Allocation Chart | National Telecommunications and Information Administration

A printed version of the most recent version of the United States Frequency Allocations: The Radio Spectrum Chart (published in January 2016 from data as of September 2015) is available from the U. S. Government Publishing Office at a cost of $6.00 per copy. You can order a copy of the chart...

www.ntia.doc.gov

 

[Dude111]

I'm guessing because when CB was introduced, there WERE no digital modes.

In my opinion its just as well...... Analogue is beautiful and is just right for 11 meters

 

[DeepBlue]

Digital requires a level of precision that would be lost with the first "golden screwdriver" that touches it. Imagine broadbanded digital noise all over the CB band, at 1,000 watts or more. No, bad idea unless the FCC wants to start licensing it again.

 

[Dude111]

Yup...... They seem to tinker inside the radio more than anyone else!!

Really though,alot of quality was lost with digital.... All these police agencies should have stayed using analog!!!

 

[FiveFilter]

I thought digital was designed and implemented to add quality, ie fidelity, clarity, whatever. How is it being lost to police agencies? Why did they change to digital?

 

[WB9YBM]

I thought digital was designed and implemented to add quality, ie fidelity, clarity, whatever. How is it being lost to police agencies? Why did they change to digital?

digital also allows data bursts to be included with the audio so a lot more information can be transferred (like location, status, etc.)

 

[WRCM]

I think it's pretty funny that some US CBers are saying things like "UK allows FM on CB! Why can't we have FM?" Meanwhile in the UK: Get 30 mile range with SSB - now Legal!

 

[buddrousa]

In 1975 you could talk AM SSB 60 to 100 miles GROUND WAVE NOT SKIP. That was using TUBE TYPE BASES TRAM D201 or BROWNING MARK III EAGLE Radios not the CHEAP CHINESE GARBAGE being sold now.

 

[RFI-EMI-GUY]

I thought digital was designed and implemented to add quality, ie fidelity, clarity, whatever. How is it being lost to police agencies? Why did they change to digital?

The requirements and expectations for P25 have changed quite a bit in nearly 20 years.

P25 does have a better SNR than analog FM. An attribute that gives it a significant advantage over 12.5 KHz narrow band FM.

However, the vocoder required to accomplish digitization introduces artifacts and distortion of the human voice and itself, is not good at rooting out human voice from background noise at the microphone.

It is advantageous for networking and simulcast to utilize digital versus analog transmission media. It is also easier to encrypt a P25 signal that is already digitized. However I will submit that the old Securenet 12kbps CVSD DES encryption sounds just fine compared to P25.

The Part 90 narrowbanding mandate that triggered this slow rush to P25 was short sited in my opinion because many commercial part 90 users abandoned 2 way LMR for cellular, thus the spectrum shortage in most areas was already solved through attrition.

Nevertheless, the radio vendors have convinced many govt agencies that P25 was somehow a federal mandate. It is not.