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I disagree, on FM this isn't an issue. If the 2 stations are far enough away that they do not interfere on analog, they would similarly not interfere on digital. It's only a problem when the two systems are close enough that analog interference would occur, then the digital signal would cause nearly identical interference. The problem is when a digital transmitter is transmitting all the time (like with trunking control channels), because the analog users would hear constant noise on the same channel (no matter how faint), rather than intermittent transmissions on a normal voice channel. Remember, a digital radio transmission is NOT a digital waveform, and therefore is no more harsh on FM than an analog transmission. The wave is still a sine wave, but the modulation being applied to it results in one of a few levels of frequency shift, since it's FM (commonly 4-level FSK is used). That means that the carrier (present whether on analog or digital) is going to shift either up one of 2 frequencies or down one of two frequencies to represent 2 bits of data (00, 01, 11, 10) rather than only one (0 or 1). What you're hearing on an analog receiver is actually the rhythmic fluctuations of the modulation, shifting up and down as the bits are transmitted. By contrast, analog is rather chaotically modulated by the actual audio being transmitted (a much messier wave, but conveniently one that you can understand as a sound wave/speech/tone/etc). At the end of the day, it doesn't matter what is modulating the carrier wave on FM. A digital signal doesn't actually go any further than an analog signal, it's just that a digital receiver can more easily distinguish, for example, one of 4 frequency shifts on a faint carrier than it could with 8 kHz of audio (including a CTCSS tone) to open up squelch. Hence, most digital radios have better sensitivity on digital (at the expense of a higher error rate in decoding the bits [known as BER - Bit Error Rate]).

This.probably has more to do with the antenna advantage mobiles have over HTs than the power boost. Sent from my SM-G892A using Tapatalk

My biggest issue with digital on GMRS is the lack of interoperability. Different modes don't talk to different modes, and analog users (which would be all FRS users and all existing type-accepted GMRS equipment) will have no hope of ever being able to understand what is being said on a digital system. The only people who'd immediately benefit from a rule change are those who aren't using Part 95 equipment. Most importantly, 95.1731(a), ((1), and (c ) would no longer be effective if stations were no longer able to communicate due to differing modulations. The FCC has already explained why they aren't going to do digital voice on GMRS, and they cite this reasoning: CTCSS/DCS is a flimsy excuse since operators using tone squelch can easily disable it to monitor for other traffic, and users with priority traffic can transmit with tone squelch. Even if they have to do it on a split-tone repeater's output frequency, there's still the chance that they'll be heard. Commercial digital radios are designed to mute traffic sent to other destinations (for example, private calls on DMR), so traffic addressing becomes a factor and impedes the capabilities of listen-before-talk. Promiscuous mode is not a standard feature. Dual certification is more difficult after 6.25-equivalent narrowbanding requirements began to get implemented in Part 90, since the radio would be capable of transmitting a non-compliant emission designator or scrambled/encrypted traffic on GMRS channels. A set of significant changes to the programming software could resolve the issue, but that's additional costs and confusion for us and less planned obsolescence for the radio manufacturers. It's not impossible for a 6.25e radio to get dual certification since there's no requirement to prevent users from programming digital channels onto GMRS channels, but it's a big can of worms for the FCC and extra costs for the manufacturer. If I had to pick a mode, and if licensing/equipment costs were assumed to be negligible, I would endorse P25 Phase 1. It's theoretically vendor-neutral, easy to modulate, better suited on simplex operation (NAC of F7E and non-talkgroup operation), and most of the equipment already out there already has mixed-mode capability. Unfortunately, we can't trust everyone to properly program their radios for mixed-mode operation and listen-before-talk. GMRS isn't the place to set up commercial-type repeater systems, it's a place for travelers and family members to talk to each other. That's why we have the amateur bands.

Part 15; same 902-928 as the amateur radio band but at very low power and cannot interfere with any other service (including ham radio). Maximum field strength of 50 uV/M at 3M which is probably about 50-100 milliwatts. Some cordless phones use 902-928. Best way to stay out of trouble is to use the middle of the band since most ham radio use is in the top and bottom 1 MHz. https://www.law.cornell.edu/cfr/text/47/15.249 I've seen comments on Youtube and elsewhere to the effect that anyone can just get a 900 MHz mobile or handheld radio and legally start transmitting without a license. That is completely untrue.

I just don't see the ban going on for much longer. I think we as a community need to step up and make a convincing case, on the record with the FCC. When they denied the requests to permit digital voice, they specifically mentioned that there was insufficient discussion about it in the record, and thus they could not make a ruling. Once a Petition for Rulemaking is filed with a very narrow set of requests (not the kitchen sink arguments that were flying around last time -- mostly due to so so many proposed changes by the FCC, we had to defend all of them), key GMRS groups and radio manufacturers will have a chance to discuss it officially on the record and the FCC can make the determination. Even still, the main issue I see with allowed digital voice is that no Part 95 equipment (to my knowledge) is even capable of being programmed to enable it. Maybe one or two models exist that carry dual Part 90 and 95 certification. Assuming the FCC even decided to lift the restriction on digital voice, one of three things will need to happen: The manufacturers will need to begin adding digital to their lineup of radios. This is not impossible, as some low-cost dPMR radios exist for Europe, but I don't see it as something they want to jump at right now. I think the tide will turn within the next 5-10 years, but that's quite far off. The FCC would need to permit GMRS licensees to use Part 90 equipment. We've been down this road before, and they pretty much completely shut down the argument. Their position seems to be that the manufacturers just need to submit their equipment for type certification and there would be no issue. The manufacturers will need to begin certifying their equipment for Part 95 as well. For whatever reason, the manufacturers seldom cross-certify for Part 95. We're only just now getting some of the Chinese radios to have Part 95 certification (much to the chagrin of some of us), but getting Motorola, Kenwood, Icom, etc to follow suit has not been going very well. GMRS and FRS were lumped together so GMRS radios ended up being seen as bubble pack radios to sell at Walmart, not for more robust communications. Hopefully now that the combo radios are no longer able to be marketed, that means GMRS will finally get some non-bubble pack love.Digital formats are finally working their way into cheaper radios (mostly DMR at this point), so hopefully the market for digital personal communications will continue to grow and the manufacturers will get serious about meeting the demand. I think this lack of motivation will be a driving factor in the FCC not permitting digital formats in the near future. I also think the bubble pack manufacturers will sit back and moan that digital doesn't do anything special and they don't want to hear complaints of interference. It will need to be a concerted effort to get this done, but I think the case can certainly be made. Everybody needs to be on the same page and the argument eventually has to be had on the record, not just online in forums.

We are not saying the FCC should require digital - just give people the option to use it if they want. Digital does not cause more interference unless you can violate the laws of physics with it

I don't think favoritism toward a particular standard would be in the best interest of the public, and likely wouldn't be specified by the FCC. What they are likely to do is specify a very limited set of emission designators which may or may not include the type of digital you're hoping to use (i.e. a TDMA format like DMR). So, if anyone has hopes of using DMR one day, they really need to make sure the FCC permits the associated emission type. For example, here are some common formats and their emission designators. The last 3 digits are significant as they designate the modulation and type: 2-slot DMR (MotoTRBO) voice 7K60FXE 2-slot DMR (MotoTRBO) data 7K60FXD P25 Phase I voice 8K10F1E P25 Phase I voice 8K10F1D P25 Phase II has several designators, of which 8K10F1W is one type NXDN 6.25kHz (IDAS/NEXEDGE) voice 4K00F1E NXDN 6.25kHz (IDAS/NEXEDGE) data 4K00F1D NXDN 6.25kHz (IDAS/NEXEDGE) voice+data 4K00F1W NXDN 12.5kHz (IDAS/NEXEDGE) voice 8K30F1E NXDN 12.5kHz (IDAS/NEXEDGE) voice 8K30F1D NXDN 12.5kHz (IDAS/NEXEDGE) voice+data 8K30F7W We are most likely to see the voice emissions allowed but not sure about the data or combined voice+data modes. Note that DMR is actually FXE and not F1E, which means an oversight (intentional or otherwise) by the FCC could exclude DMR simply my omitting its emission type. Now back to my opinion, I prefer DMR. Early on NXDN was a winner in my eyes, but once DMR became more openly supported and the Ham community embraced it, it has become the clear winner. Since we cannot benefit from 6.25 kHz channels on GMRS anytime soon, narrowband NXDN doesn't do anything for us except minimize adjacent channel interference, which typically isn't a big problem on GMRS to begin with. We just don't want to be locked into a particular standard and then when something new and improved comes out, we're locked in by the Part 95 rules. If it meets the emission designators, it would be open to use. TDMA systems like DMR, however, allow us to use a 12.5 kHz channel (really a 25 kHz channel, but we're occupying 12.5 kHz in this case) with 2 time slots, or virtual channels. This doubles our efficiency on a given channel, even if GMRS isn't so busy to really need it right now. It would be good for putting up one repeater and having 2 distinct usages like a private slot for the individual/family putting up the system, and a slot open for the public to use. The two groups can coexist and transmit simultaneously without affecting each other.