intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 3 hours ago, UncleYoda said: I hate everything about DMR. I particularly hate the way it's taking up frequencies in HAM. I would file for a refund of my GMRS fee if the FCC implemented your proposal. Digital should get its own bands and not take over our analog frequencies. Ah! Another benefit of DMR: less users, which means less congestion. What model DMR radio do you use? Quote Link to comment Share on other sites More sharing options...
WRUU653 Posted May 29, 2023 Report Share Posted May 29, 2023 21 minutes ago, intermod said: This plan would not replace analog - both would be permitted. Analog is never going away. The people wanting to use digital must get a digital radio. But there is no need for anyone else to do this. For example, if I have a analog repeater today, and I need more capacity, I have two options. Replace it with a DMR repeater on the current 462.625 channel center, or move it +/- 5 kHz up or down. The former is really a waste of spectrum. The latter would provide me with two channels, and leave the other half of the channel open for another DMR repeater if another group wants their own repeater. I do agree that analog will always be here but are you saying the two wouldn't interfere with each other? Quote Link to comment Share on other sites More sharing options...
Lscott Posted May 29, 2023 Report Share Posted May 29, 2023 On 5/29/2023 at 1:07 PM, WRUU653 said: I do agree that analog will always be here but are you saying the two wouldn't interfere with each other? I’ll chime in here. What would likely be done is a mixed mode repeater. It auto detects the mode in use. That would still preserve the analog user’s ability to continue to use their equipment. I would DEFINITELY not recommend installing a digital only repeater. Of course the tiny sticking point is getting the FCC to change the rules to allow ANY digital voice mode on GMRS. And I do have some thoughts on that. GMRS Digital Voice - 20221011.pdf WRUU653 1 Quote Link to comment Share on other sites More sharing options...
WRUU653 Posted May 29, 2023 Report Share Posted May 29, 2023 I must admit I started to ask another question and then decided I should read that pdf first @Lscott, I found it to be informative. Thanks. Lscott 1 Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 11 minutes ago, Lscott said: That’s only true if the radios are able to “effectively” coordinate time slot synchronization between themselves. Usually the repeater does that task. On simplex that has to be done by the user’s radio. The feature is typically referred to as DCDM, dual capacity direct mode. Some radios will just transmit on both time slots in simplex mode. Correct that the radios must sync themselves when operating in direct mode; DCDM is one method to provide for two simplex conversations on one channel. They could still use the +/- 5 kHz channel center, and they would hear the repeater. But compliant DMR radios don't use both timeslots simplex/direct mode; they use an arbitrary slot established by the first radio that transmits. They still only transit 50% of the time (the transmitter keys on an off every 30? or 60? milliseconds - forget the number). Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 40 minutes ago, WRUU653 said: I do agree that analog will always be here but are you saying the two wouldn't interfere with each other? If my analog repeater did not interfere with another today, replacing it it with a DMR repeater (same antenna, same power level) would not change the interference potential. If I added a new repeater near an existing repeater, then interference may result if they are too close. But it would not matter if the new repeater was analog or digital. Interference has more to do with signal strength of the two signals (the desired versus the undesired signal) than the technology. However, I will say that digital can be more annoying to listen to if you are receiving it on an analog radio. Analog signals are just more susceptible to interference than digital. But this is what CTCSS is for. This is why we can place two digital repeaters closer together than two analog repeaters on the same channel. Quote Link to comment Share on other sites More sharing options...
wqnd300 Posted May 29, 2023 Report Share Posted May 29, 2023 This discussion needs to end because the answer is not digital or cutting a high level repeater down to 25 watts. If you want more frequencies or digital modes go to amateur radio and leave gmrs as it is. What does need to happen is more education as people need to understand that gmrs is not the same as a cellphone so you shouldn't use it like one and talk for hours. Sent from my SM-S918U using Tapatalk gortex2 1 Quote Link to comment Share on other sites More sharing options...
Lscott Posted May 29, 2023 Report Share Posted May 29, 2023 8 minutes ago, intermod said: But compliant DMR radios don't use both timeslots You would think so. Trouble is some cheap radios out there may not. I think that was done to eliminate having to worry about which time slot the other radio was using. The first model Baofeng DMR radios were notorious for spamming both times slots. That was OK on simplex but killed the DMR repeaters. On some of my newer Kenwood DMR radios there is an option to use either the existing DCDM standard, which will decode audio from either time slot, or the newer one where they have to match. Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 3 hours ago, WRQI583 said: While it sounds like a good idea, with GMRS being unregulated when it comes to setting up repeaters, it would, in some areas cause bad problems. GMRS would have to turn all digital or stay all analog. With the amount of bubble pack radios out there doing analog, it wouldn't make sense to have it change to DMR. In my area alone, we are maxed out on GMRS repeaters when it comes to the 8 pairs, which rarely get used. The majority of the communications you hear are businesses and schools on the bubble pack radios. Adding DMR to that would cause a real issue. If I replaced my analog repeater with a digital one, how would that cause more interference that my analog repeater if my analog did not interfere today? Quote Link to comment Share on other sites More sharing options...
Lscott Posted May 29, 2023 Report Share Posted May 29, 2023 3 minutes ago, wqnd300 said: If you want more frequencies or digital modes go to amateur radio Could have said the same thing about CB. But as the popularity increased the FCC finally authorized additional channels, from the original 23 to the now 40. And the past year or so added FM mode to the current AM and SSB modes. Quote Link to comment Share on other sites More sharing options...
WRUU653 Posted May 29, 2023 Report Share Posted May 29, 2023 13 minutes ago, intermod said: However, I will say that digital can be more annoying to listen to if you are receiving it on an analog radio. Analog signals are just more susceptible to interference than digital. But this is what CTCSS is for 9 minutes ago, intermod said: If I replaced my analog repeater with a digital one, how would that cause more interference that my analog repeater if my analog did not interfere today? All of your statements seem to focus on your idea that this won’t interfere with analog repeaters. Not all communications are through repeaters. Why should people be forced to use CTCSS in simplex? Raybestos 1 Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 3 hours ago, WRQI583 said: I am not against DMR. It is the only digital voice mode I use on Ham Radio and I absolutely love it. For the GMRS application, if DMR were to be introduced as the sole means of communication, that would have had to have happened back before they flooded the market with bubble pack radios. Back in the day where GMRS was GMRS and FRS didn't exist. I think what the FCC should do is find a set of frequencies near GMRS and give us another 8 just for DMR. With everyone abandoning the VHF and UHF lower portions of the bands to get on 800 MHz and also with the FirstNet network, there are going to be a lot of empty frequencies across the nation. The VHF low band is a good example. For $35 a license, I think they can spare some. DMR is a good idea when it comes to utilizing bandwidth, plus, you can add networks to it. But, like many will say, that is what you have Ham Radio for. While that is true, I think more people would utilize radio if they could have that element of Ham Radio, but without having to take a test. Agree that having a set of new frequencies for any digital technologies would avoid some conflicts. VHF and UHF is getting really quiet. I wonder if you just found win-win between GMRS licensees and the business frequency coordinators (BFC). If the BFCs can make ~$35 per licensee (as opposed to $200-$300 for one license over a large area), they may make more money supporting GMRS. But it seems that building coalition of interested GMRS licensees to lobby for digital would be more attainable. We have been using a DMR repeater on GMRS since 2016 (at 2200' elevation). Its runs dual mode (analog an digital). We have had no formal complaints, and I am aware of a few other GMRS systems also running DMR. So presenting the FCC with several successful DMR trials seems like an easier approach. Not sure I understand how the flood of bubblepack radios impact digital. Do you mean there are too many existing analog radios to change them all out? I am not suggesting analog be eliminated - we would allow digital to-co-exist with analog. 99% of those bubblepack radios come pre-programmed with tone squelch activated so they never even hear the digital signals or anything else for that matter. And digital signals are not bothered much by analog or other digital signals. Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 4 hours ago, WRUU653 said: It seems someone always wants to change GMRS. Other ideas I don’t think would work… painting two lanes for cars but trucks get there own overlapping lane to drive down the middle… yeah but it’s more lanes and cars can fit there, doesn’t it sound great? Being from California, I will admit we are victims of a few social-engineering projects that have gone, well, very badly. and we love sharing our great ideas with otehr states. But this will be different! Are you suggesting that we cannot trust our own government? But from another perspective - a digital transition is inevitable. Regardless of whether it worsens or improves things. This is because of commerce and greed (the American way). If GMRS licensees do not take this head-on now, the radio industry will do it for us (or "to" us...). We will not like the outcome. Evidence: the FCC's 2017 ruling that allowed unlicensed users on the 462 GMRS channels with two watts. That was likely the industry's influence. But as I outlined in other posts, if I replace my existing analog repeater with a DMR repeater, how would that create a problem for others? Now, if the area is already congested with repeaters, and I try and jam in a new repeater too close to others - DMR or analog - we may have a problem. But that is independent of the mode of the repeater, and its no different that the problem we have today. Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 4 hours ago, WRXD372 said: ... and "out of the box / instant" FUN !!! Case closed ...but fades fast... Thankfully the kiddies with their bubblepack radios and annoying call buttons fade fast (or break).... Quote Link to comment Share on other sites More sharing options...
WRUU653 Posted May 29, 2023 Report Share Posted May 29, 2023 22 minutes ago, intermod said: Agree that having a set of new frequencies for any digital technologies would avoid some conflicts. This is the only case I see as a way to do this if it’s done. 22 minutes ago, intermod said: Not sure I understand how the flood of bubblepack radios impact digital I don’t have any concerns with how existing analog affects digital. I’m concerned with the idea digital affecting existing analog and I don’t think CTCSS is a reasonable solution. That’s like building a stadium next door and telling people if they don’t like the lights at night they should build a bigger fence (sorry about not being able to see out of your windows). You mention the the rule change FRS/GMRS. I don’t think GMRS was a problem with new FRS/GMRS radio back when this happened it was the new radios impacting the existing GMRS. Have we learned nothing from this blunder? I do appreciate the exchange of ideas discussed here. I think if this were to happen it needs to be solution that works for everyone. Raybestos and gortex2 2 Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 1 hour ago, WRUU653 said: All of your statements seem to focus on your idea that this won’t interfere with analog repeaters. Not all communications are through repeaters. Why should people be forced to use CTCSS in simplex? I see your point on nuisance interference to simplex users. So if I wanted to listen in carrier then I would be annoyed if there was a strong DMR "chainsaw" going. As I am in a dense suburban and urban environment, the contractor/bubblepack call tones/business traffic is so constant that I never go without CTCSS, even in simplex mode. We can no longer listen in carrier squelch mode. Back in the day we could work long-distance simplex or repeaters. This was caused by the FCC, and Chinese radio manufacturers who have discovered the GMRS market and flooded it with radios. So maybe the FCC should only permit digital in areas where everyone is already running CTCSS/DCS....maybe this is why we have had few complaints from others (we have been running a DMR repeater on GMRS since 2016). But from a really practical perspective, once the FCC permitted repeaters in GMRS, simplex users were no longer granted protection from repeater interference in any case. They effectively became secondary, so they must accept interference or move to another channel (or use CTCSS for nuisance interference like DMR or analog). Once the industry started addressing digital, they may even come up with a better squelch system for radios. I have always wished I could program a given channel position on my analog radios to decode more than one CTCSS/DCS code at a time (or, decode/unmute when *ANY* CTCSS/DCS code is present). Thus, when it heard a DMR, NXDN, P25, noise, etc. it would not unmute. This should be really simple with current DSP technology. But it would also mute simplex traffic with no CTCSS....so maybe there is an even better way: mute all digital traffic. Quote Link to comment Share on other sites More sharing options...
Lscott Posted May 29, 2023 Report Share Posted May 29, 2023 Some radios the CTCSS gets spoofed by the pulsing nature of DMR and the squelch opens. Quote Link to comment Share on other sites More sharing options...
Lscott Posted May 29, 2023 Report Share Posted May 29, 2023 1 hour ago, intermod said: We have been using a DMR repeater on GMRS since 2016 (at 2200' elevation). Is that running under an experimental license from the FCC? If not then you’re asking for the kind of attention from the FCC you don’t want. Quote Link to comment Share on other sites More sharing options...
MarkInTampa Posted May 29, 2023 Report Share Posted May 29, 2023 The strongest GMRS repeater by far in my area runs analog and P25 and has been for years. It's not exactly a secret, the NAC is published on their web page. P25 is seldom used, maybe a few times a week but almost every time it is used I'll hear folks freaking out about "what that noise is", "isn't that illegal", "how do I block it", etc. It's not my repeater so I really don't care. We also had a repeater move frequency a month or so ago move due to somebody running encrypted DMR on the same frequency and causing interference with his repeater. That kinda sucks for me, now I have two repeaters (one 10 miles west, the other 35 miles southeast) pegging the S-meter on the same frequency but at least they are on different tones. Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 3 hours ago, Lscott said: I’ll chime in here. What would likely be done is a mixed mode repeater. It auto detects the mode in use. That would still preserve the analog user’s ability to continue to use their equipment. I would DEFINITELY not recommend installing a digital only repeater. Of course the tiny sticking point is getting the FCC to change the rules to allow ANY digital voice mode on GMRS. And I do have some thoughts on that. GMRS Digital Voice - 20221009.pdf 286.2 kB · 2 downloads This is a interesting paper. Particularly for our current conversation: "...First let us look at the currently authorized emissions for GMRS. Looking in 47 CFR Subpart E 95.1771 we find some surprising, authorized voice emission modes, A3E, H3E, J3E and R3E. All of these are several types of voice amplitude modulation, Single/Double Sideband with suppressed or reduced carrier etc. None of these official modes are compatible with the FM mode! Why isn’t the FCC worried about interoperability between FM and these modes?..." Was this ever submitted to anyone at the FCC (officially or otherwise?) kc9pke 1 Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 3 hours ago, wqnd300 said: This discussion needs to end because the answer is not digital or cutting a high level repeater down to 25 watts. If you want more frequencies or digital modes go to amateur radio and leave gmrs as it is. What does need to happen is more education as people need to understand that gmrs is not the same as a cellphone so you shouldn't use it like one and talk for hours. Sent from my SM-S918U using Tapatalk OK - everyone - please stope this discussion. I will advise Rich to disable further comments. Sorry to offend you. Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 3 hours ago, Lscott said: You would think so. Trouble is some cheap radios out there may not. I think that was done to eliminate having to worry about which time slot the other radio was using. The first model Baofeng DMR radios were notorious for spamming both times slots. That was OK on simplex but killed the DMR repeaters. On some of my newer Kenwood DMR radios there is an option to use either the existing DCDM standard, which will decode audio from either time slot, or the newer one where they have to match. That is a problem...makes me wonder if this was really dPMR? G Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 1 hour ago, Lscott said: Some radios the CTCSS gets spoofed by the pulsing nature of DMR and the squelch opens. I have seen that too. I experienced this on low-end equipment. G Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 1 hour ago, Lscott said: Is that running under an experimental license from the FCC? If not then you’re asking for the kind of attention from the FCC you don’t want. Correct - experimental. The purpose was to "establish whether digital operation could co-exist with analog on shared spectrum". So far we have shown that it can. We simply replaced an existing analog repeater with a dual mode model (analog/digital) at the same power level. So our analog users still use it normally. ABout 10% of the regular users operate DMR/analog radios. Quote Link to comment Share on other sites More sharing options...
intermod Posted May 29, 2023 Author Report Share Posted May 29, 2023 50 minutes ago, markskjerve said: The strongest GMRS repeater by far in my area runs analog and P25 and has been for years. It's not exactly a secret, the NAC is published on their web page. P25 is seldom used, maybe a few times a week but almost every time it is used I'll hear folks freaking out about "what that noise is", "isn't that illegal", "how do I block it", etc. It's not my repeater so I really don't care. We also had a repeater move frequency a month or so ago move due to somebody running encrypted DMR on the same frequency and causing interference with his repeater. That kinda sucks for me, now I have two repeaters (one 10 miles west, the other 35 miles southeast) pegging the S-meter on the same frequency but at least they are on different tones. I think I might know about that P25 system. The FCC is short-staffed as has little interest in pursuing things like this unless many complaints come in. However, is there a victim here? We have had the same response here from some new users. Now I provide a URL link to a recording of what DMR sounds like on an analog radios so that they don't keep trying to access the repeater when its being used for DMR, or complain that there is noise. Or show them what a busy light is. The encryption issue is a bit more serious. It is just one checkbox in modern Part 90 gear and your encrypted. No sure encryption on shared channels is really the right thing to do. Using Part 95 equipment certification would likely solve most of that on GMRS. Quote Link to comment Share on other sites More sharing options...
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