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DMR channels do not use 7.6 kHz of spectrum; they each use 12.5 kHz but they use time division multiplexing to share that portion of spectrum. In other words each current GMRS channel would only represent two DMR channels. Gil is correct that this would impact everyone who has an analog GMRS radio. Use of such a radio requires the entire channel, making it unavailable for DMR. Conversely, to those who have analog radios, every DMR transmission sounds like an impact wrench. “Here in California, CERT, neighborhood or fire watch, militia groups, etc. have implemented GMRS because 80-90% of their members have no direct interest in the technical aspects of amateur radio.” I don’t know how true that statistic is, but ruining GMRS for the rest of us isn’t the answer. P.S. People who have no direct interest in the technical aspects of amateur radio might have a tough go when they have to program a codeplug. DMR codeplugs are extremely technical. I guess you could sell the radio with a basic codeplug that’s simplex DMR on 1-22 and duplex on 23-30, but what do you use for talk groups, time slots, and color codes?

The eight current GMRS channels can handle eight simultaneous conversations today (in the same area). The proposal below would allow for 32 simultaneous conversations without expanding the GMRS service. For those not familiar with DMR technology, each DMR repeater signal has two "timeslots" which allows for two independent talk channels. Two DMR signals can fit within the same space as one analog FM signal today. This is possible because a DMR signal only requires about 7.6 kHz of spectrum, while todays wideband analog signals need 20 kHz of spectrum. Thus, four conversations can be supported within each of the current GMRS channels. The center frequency of each DMR repeater (and the radios it supports) would be programmed 5 kHz above or below the current center channel. +/-12.5 kHz might also be used. Below shows how this would work in reality. The FCC would not need to allocate new radio spectrum. They only have to allow more efficient use of what we already have. The other benefit of DMR is that two different repeater groups could invest in one DMR repeater, which splits the cost in two while each maintains their own "channel". As a DMR repeater takes the same rack space as an analog repeater and only requires one antenna, the repeater site lease costs could be split between the two groups as well. It would take the FCC some time to accomplish this, so if they started now, they might be able to complete this rule change in 2024.

I'm pleased to announce a new feature available on the forums: a new classifieds system! Premium Members can post a listing for radios, repeaters, antennas, and more that they are selling or want to buy. All members can view and purchase items from the seller, a Premium Membership is only required to post advertisements. Purchases are handled between the buyer and seller directly at this time, but we might expand this in the future to handle payments similar to how eBay and PayPal work. There are no commissions since we are not handling the payments on behalf of the parties. If you are a Premium Member, you will see a blue "Submit an advert" button on the Classifieds page. Click on this button and select the category to list your ad under. Listings are active for 21 days for free (less the cost of membership) and can be renewed if the item is still available. You also have the ability to set up shipping options for the buyer, and can paste the tracking number for the shipment once you've completed a sale.

One other point. Just how many people check to see if they can reliably communicate using simplex? If they can then they should stay off the repeater, use simplex, and let those who REALLY need it the access.

Then stop putting repeaters on top of other repeaters! Simple solution because you don't need more than a few. Here in Southern California we have idiots that need to shut up and allow others to periodically use the frequency. Those are the real issues. Sent from my SM-S918U using Tapatalk

And of course no one will have to buy new radios to use this because the old ones will still be compatible with these new proposed specs and the FRS bubble packs out there shouldn’t be an issue either… It sounds like something that the people who sell radios would be behind though. ?

Which three were off when the Mike stopped working? What functions stopped working as designed? You probably documented where the other five went before you removed them. Which pins did they go to?

Never mind - I finally found it. Thanks for the assist WRUU653!!

You have your license and you are in one of the required areas. All you should need to do now is join mygmrs.com forums then you will have access to their web page on this site and hit the join button on their page. ? They have a webpage also https://midwestgmrs.org.

You are correct, it should. Try sending Rich a message https://mygmrs.com/contact you can report your own post too. Maybe log out and log in???

We can't do much about the ads, but the dots show a concentration of repeaters. The dot color corresponds to how many repeaters are in that area. As you zoom in, the dots get closer to blue and the number shinks, until you zoom in enough to see individual repeaters on the map. Once you zoom in close enough and click on a single repeater, the green area highlights the forecasted coverage area. I'm not sure about the other questions.

Thanks - got one workming. All help much appreciated. Thank you

There is no need to scan 23-30 -- the output of the repeater channels are the same frequencies as 15-22; just make sure there are no TONES specified for the channels you are scanning (if a Rx tone is defined, you will only hear traffic if the transmitter sends the same tone). Confusingly, you state channels 1-30 in one spot, but also mention "20T" and "r20T" -- I don't know what the "T" represents, unless it means there is a tone defined; "r20" is usually the same thing as channel 28, radios tend to use EITHER 23-30 OR R15-R22 -- the repeater counterpart to simplex channel 20. Per the FCC regulations: (emphasis is mine). The GMRS service was /never/ considered to be a general "talk-to-anyone" chit-chat service -- it was meant for stuff like large family farms wherein one might have a base/repeater set-up at the farm house, and family members in the fields would carry HTs or maybe a tractor mounted mobile. In those days, one's license was good for ONLY two of the main/repeater frequencies (so good luck finding someone else using the same frequencies on their license) and the seven GMRS 5W interstitials. Heck, even the CB service, before the 70s, only allowed for license<>license calls on a limited number of frequencies, the rest were meant for calls between family members sharing the license. FYI: USB/LSB are not "special channels" -- they are modulation schemes using the same channels as regular AM. AM modulates/transmits both sidebands, where Single Sideband suppresses one, putting the power into the other sideband (and using half the overall bandwidth). I'm not familiar with anyone who "pays bad money" for stuff -- except counterfeiters ? However, this sounds more like a case of not paying to research the GMRS service before buying equipment. ADDENDUM (2023/05/31): I may sound a bit harsh above. Saturday was a bad day for me with side-effects from chemotherapy (chemo is on Tuesdays, but the side-effects seem to peak Friday/Saturday). I'm not retracting anything since all the bullet points are still valid -- and not worth trying to adjust phrasing after half a week of viewing.

Jeesuz.. "Some people" could over-complicate a spoon in their desperate attempts to show everyone how smart they think they are. The answer, which unbelievably even after all those words was still not actually answered, is: NO

I agree with the GMRS statement, but I see lots of 70cm repeaters in California in which the offset is positive or negative (but always 5MHz).

In Amateur Radio and GMRS the offset is always up (+) 5 megahertz. So, if the receive frequency is 444.xxx, the offset is 449.xxx. or, if the receive frequency is 462.xxx, the offset is 467.xxx. Amateur Radio and GMRS are 2 distinctly different services. Do you want to learn about Amateur Radio, GMRS, both or radio communications technology in general?

My repeater antenna is attached to a single 10Ft section of a telescoping flag pole on my roof.. i'm sure there is some fancy differences between a flagpole and a mast, but my flagpole/antenna combo lived through one of the worst wind-storms in memory last year and the antenna gets many farz.