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GMRS narrow band compliant equipment?


Lscott

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I read from time to time proposals to switch GMRS from normal FM to narrow band FM, 2.5KHz deviation, and the arguments for and against it including repeater owners.

 

One of the questions that seems to get little attention is just how prevalent are narrow band FM capable radios out there that are in use? Any legitimate proposal to go narrow band has to address this question.

 

I use several that can do both normal FM and narrow band FM, primarily Kenwoods like the TK-370G, TK-3170, TK-3140 to mention a few.

 

The other point is how many of the current offerings from the likes of Midland, Btech and others that can do both or just narrow band like Midland that gets often mentioned?

 

The point I want to get to is if the majority of radios currently, or at some point in the future, are just narrow band, because that's what people buy whether they know it or not, could be the tipping point where the FCC says GMRS is going narrow band. If most radios at that point are narrow band the disruption for the majority of users would be small so the FCC isn't going to worry so much about the small number of wide band radios out there.

 

The FCC sort of did this with the combo FRS/GMRS radios where almost nobody was getting a license to use the GMRS channels. So they just changed the rules to reflect how the radios were really getting used. They didn't seem to worry much how this impacted GMRS users at the time. 

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One of the questions that seems to get little attention is just how prevalent are narrow band FM capable radios out there that are in use? Any legitimate proposal to go narrow band has to address this question.

 

 

An "I think", I don't know that this would be easy to confirm.  We could probably get sales data from manufacturers for 2 or 3 decades of sales, assume x% are no longer working and x% exported.  It would still be a guess, but may be close.

 

This brings three questions to mind for me.  Who will do the leg-work? Will the manufacturers be willing to play ball?  Would polling the user community have any value?

 

 

 

The other point is how many of the current offerings from the likes of Midland, Btech and others that can do both or just narrow band like Midland that gets often mentioned?

 

 

I think the same as above.  We would have to poll manufacturing data... though that should be a bit easier since the performance data is public information.  Anecdotally, no Midland radios I have owned have WB. All of my BTechs did both.

 

 

 

The point I want to get to is if the majority of radios currently, or at some point in the future, are just narrow band, because that's what people buy whether they know it or not, could be the tipping point where the FCC says GMRS is going narrow band. If most radios at that point are narrow band the disruption for the majority of users would be small so the FCC isn't going to worry so much about the small number of wide band radios out there.

 

 

I believe this is a commercially driven, supply side debate, more of a 'what if'.  If the demand is there and manufactures are willing to invest in the market, then that would swing policy more so than the individual users, such as family units.

 

That said, obviously, you can't completely rule out the Legislature and/or the FCC following the natural flow in a direction of all NB.

 

 

 

The FCC sort of did this with the combo FRS/GMRS radios where almost nobody was getting a license to use the GMRS channels. So they just changed the rules to reflect how the radios were really getting used. They didn't seem to worry much how this impacted GMRS users at the time. 

Agreed.  They also did it with Citizens Band, deregulating that (for the most part) and getting rid of license requirements. 

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You have some good points marcspaz.

 

About it being market driven, wide band verses narrow band, could get a boost by the manufactures. If they are already narrow band compliant it would be a marketing incentive for them to point it out to customers. Second any wide band equipment only, mostly used, would be eliminated from the market. Now users are pushed into buying more from the narrow band new equipment market and less from now smaller compliant used equipment market.

 

On the regulation front manufactures could point out to the FCC they have good sales of their narrow band radios and few requests for wide band equipment. The FCC could then infer the consumer has a preference for narrow band equipment, or at least don't find it a limiting factor in how they use their radios. Making a decision to go narrow band for GMRS would be an easy one I suspect for the FCC.

 

On the engineering side of things it's rather a screwy situation where you have two different radio services assigned the same spectrum but with different technical specifications for bandwidth. If the goal was really to allow the two to interoperate the FCC screwed it up. Having one station on frequency running wide band and another running narrow band results in some annoying messing around with the volume control. It's either to loud or too soft depending on who is doing the RX'ing and the TX'ing. By the way this happens with DMR when people don't get their audio levels set right. One minute i can hardly hear one station and the other station blows be out of the chair.

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On the engineering side of things it's rather a screwy situation where you have two different radio services assigned the same spectrum but with different technical specifications for bandwidth. If the goal was really to allow the two to interoperate the FCC screwed it up. Having one station on frequency running wide band and another running narrow band results in some annoying messing around with the volume control. It's either to loud or too soft depending on who is doing the RX'ing and the TX'ing. By the way this happens with DMR when people don't get their audio levels set right. One minute i can hardly hear one station and the other station blows be out of the chair.

 

Wow... this is perfect!  I couldn't agree more, with all of this.  I can't understand for the life of me, why the FCC would have two distinctively different services, sharing frequencies.  They didn't even bother setting a primary and secondary service.

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There are 1659 repeaters listed at myGMRS.com and assuming that 20% are inactive and or otherwise not on line, that still leaves 1328 repeaters. How many of those are WB versus NB?

 

I would submit that most of them are surplus WB "legacy" repeaters. Many owners have a ton of money invested in them, so if GMRS were required to go NB only, I'd bet that many of them would simply pull the plug, thus impoverishing the utility of the service.

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Changing GMRS from wide to narrow band would be an easy way to get rid of GMRS completely.

 

The elimination of wide band radios and repeaters would leave most serious GMRS users discouraged with the thought of replacing their equipment.

 

The FCC could use the argument that as both FRS & GMRS share frequencies they should both use the same band width.

 

The reduction in usage would justify eliminating both radio services.

 

Just saying.

 

Keith T

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Changing GMRS from wide to narrow band would be an easy way to get rid of GMRS completely.

 

The elimination of wide band radios and repeaters would leave most serious GMRS users discouraged with the thought of replacing their equipment.

 

The FCC could use the argument that as both FRS & GMRS share frequencies they should both use the same band width.

 

I wouldn't say changing from WB to NB is an easy way to get rid of GMRS. The real question is just how many people are running NB now and don't even know it? I see frequent questions about Midland equipment which seems to be NB only. Apparently they sell enough of them. If the FCC switched to NB those users wouldn't notice and most likely wouldn't care since their radios would continue to work reasonably well after the switch.

 

The question of how it would impact repeater owners and users all depends on what equipment they use. If the repeater owner used old Part 90 radios that have both WB and NB capability the switch wouldn't be all that big of a deal. Same for ordinary users. In my particular case most of the HT's I have include both WB and NB functionality. All I need to do is fire up the computer, dig out the programming cables, read the codes plugs, switch bandwidth and then writing them back. Done. A bit of work but not a show stopper. Most of my radios already have dual sets of memories programmed, one for WB and another for NB. Yes it's a pain to flip from one to another depending on bandwidth but I can do it when necessary.

 

Your last point is an excellent one. Sooner or later the FCC is likely to address this with another rule change "tweak". Expecting FRS radios to disappear to solve the problem isn't realistic. There are far too many of them. Perhaps as a group we could start a move towards NB operation for those that have the equipment. After a period of time, with enough GMRS users have switched, any potential forced switch by the FCC won't be so painful.

 

Also a suggestion by others changing the rules to make GMRS the primary service and FRS secondary likely will fail too. People purchased the old combo FRS/GMRS radios, never read the instructions advising the necessity of getting a GMRS license, or just didn't care and used all the channels anyway. Expecting those kinds of people to respect, understand or yield the frequency to the primary user will result in about the same compliance experience, little to none.

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There would be one benefit to moving to NB operation for GMRS. Additional channels would be available in the same spectrum band. Some claim the service is under utilized now so extra channels wouldn't be needed. However the point to consider are the frequent questions I see posted about running DMR radios in the GMRS service. With newer NB channels the old ones would continue to be analog only while the newer ones would be reserved for DMR operation. This was done basically in the European PMR446 service with Digital PMR446. Originally it was analog only now they allow digital operation. DMR tier 2 uses a NB channel width of 12.5 KHz.

 

https://en.wikipedia.org/wiki/PMR446

 

https://en.wikipedia.org/wiki/Digital_mobile_radio

 

https://dpmrassociation.org/dPMR-a-brief-overview.html

 

DMR uses TDMA, two time slots, thus two digital voice channels would occupy one NB channel effectively doubling the number of users.

 

The mess with FRS radios can be mitigated with this change also by restricting FRS radios to the currently assigned analog channels. Licensed GMRS users and DMR enabled GMRS radios would have access to both, analog and digital, channels. With some firmware updates existing radios could easily be made available at an affordable price. Some have mention the Anytone analog/DMR radios, D878UV for example, and with a firmware change would likely work just fine.

 

https://www.bridgecomsystems.com/products/anytone-at-d878uv-plus-bluetooth-gps-programming-cable-with-support

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To have DMR would be nice, but narrowbanding GMRS will not open new channels for digital. They are already in use by FRS analog.

Alex, unfortunately you're right. 8-( I didn't look carefully at the exact channel layout for both services. The combining of main channels with interstitial ones screwed me up. I found a document on line that shows in a nice graphical format how the two services frequencies relate to each other. 

 

Scroll down to last page and it is obvious what is going on.

 

https://apps.fcc.gov/kdb/GetAttachment.html?id=biZxuanIfZOUqdjvLHdsyw%3

D%3D&desc=888861 D01 Part 95 GMRS FRS v01&tracking_number=239603

 

So as you pointed out the spectrum does look full.

 

What is interesting are the GMRS interstitial channels sandwiched between the main GMRS channels. Its bad enough the low power FRS channels can cause interference on the main GMRS channels now we have the potential of higher power GMRS main channels partially overlapping the Interstitial GMRS channels. Then there is the potential interference of the Interstitial FRS and GMRS channels 8 through 14 with repeater input channels. The requirement that GMRS and FRS must be NB with a max of 0.5  watts is obviously to minimize interference on the GMRS WB repeater inputs frequencies. This is a mess. 

 

The interference issues could be mitigated by moving GMRS to NB. That would at least eliminate the multiple channels overlapping due to differences in bandwidth.

 

Since the spectrum is full my idea of of going NB to get extra channels is not going to work in the existing allocated spectrum. Its very unlikely but the FCC could allocate a few new channels specifically for DMR use.

 

As far as allowing DMR within the existing spectrum, well somebody will have to tolerate mix mode operation on one or more channels. Allowing DMR repeaters on several of the channels maybe worth thinking about. You get effectively two voice channels on one frequency pair. There is a lot of experience and knowledge on how to do DMR repeater linking from the Ham bands which could be applied to GMRS.    

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...The combining of main channels with interstitial ones screwed me up. I found a document on line that shows in a nice graphical format how the two services frequencies relate to each other. 

 

Scroll down to last page and it is obvious what is going on.

 

https://apps.fcc.gov/kdb/GetAttachment.html?id=biZxuanIfZOUqdjvLHdsyw%3

D%3D&desc=888861 D01 Part 95 GMRS FRS v01&tracking_number=239603...

 

The URL you posted was mangled. The correct page is here.

 

As you note, other than the 8 467mHz repeater input (467 MHz GMRS Main) channels, the two services now essentially only differ by power and bandwidth restrictions.

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I like wideband. It sounds sweet and smells like victory. However, as was pointed before, GMRS will likely go narrowband because of attrition of available wideband radios, even without any regulatory effort. In what time, who knows, maybe another 20 years or so. I would think, just enabling DMR (or any digital? P25?) on existing channels, both FRS and GMRS, at existing power levels, will be ok solution. Like now we have to avoid interference to each other with analog, we will have to play nice together with digital.

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Do you know what a forum like this would look like if they allowed dmr on those frequencies. Gmrs/frs were meant to be pretty much plug and play.

 

Have Bob and his family trying to do a code plug would be a nightmare for all. Couple that with big companies saying how easy it is to program.. I have seen seasoned hams have a hard time with.

 

I suspect alot more of the services being narrow banded to squeeze as much as they can out of the services. If you are talking about pre-installed code plug then maybe.

 

Sent from my SM-G975U using Tapatalk

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Nothing stops anyone today from running Narrowband in GMRS. If the repeater owner thinks that setting the receive window to 12.5 Kc will improve the receiver performance for their particular situation, they can do it.

 

Most repeater owners run 25 Kc wideband because it works better and sounds better. The day that 12.5 becomes the better alternative is the day most will switch. In most parts of the country there is ZERO issue with channel congestion in GMRS.

 

I'll keep mentioning this until folks get it. If you want to run DMR, there's nothing stopping you except for a Part 90 license. Go get yourself coordinated for a Private Carrier license for DMR, and invite all your friends and family to join in. You'll be talking Digital in no time.

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Nothing stops anyone today from running Narrowband in GMRS. If the repeater owner thinks that setting the receive window to 12.5 Kc will improve the receiver performance for their particular situation, they can do it.

 

Most repeater owners run 25 Kc wideband because it works better and sounds better. The day that 12.5 becomes the better alternative is the day most will switch. In most parts of the country there is ZERO issue with channel congestion in GMRS.

 

I'll keep mentioning this until folks get it. If you want to run DMR, there's nothing stopping you except for a Part 90 license. Go get yourself coordinated for a Private Carrier license for DMR, and invite all your friends and family to join in. You'll be talking Digital in no time.

 

I actually run 2 of my 6 repeaters in NB and most likely will be switching another to NB in the near future. For those that run the Midland gear it does help those radios. I still like my WB stuff but i use what makes it work best for the users on the system. As you said its all whats best for the repeater owners and users. I wouldn't want the FCC to say you MUST go NB cause i would be unplugging half of mine.

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