Universal Digital Voice

Bob/K0NR operates VHF/UHF FM from Pikes Peak for the June VHF contest.

For the June VHF contest, I operated Single-Op Portable from the summit of Pikes Peak. I combined this with Summits On The Air (SOTA) and Parks On The Air (POTA) activations. In a few hours, I made 80 QSOs on 6m, 2m, 1.25m, 70cm, and 23cm bands. It was a fun time.

Quite a few of the contacts were made on 2m FM, The Utility Mode. Even though CW, SSB and WSJT modes are more efficient (especially with weak signals), FM is still the least common denominator for modulation. Everyone has it, so there are more QSOs available with that mode.FM is the default choice for easy VHF simplex communication.

Where Be Digital?

Perhaps it was the lack of oxygen in my brain, but I started to wonder:

Why the heck, in the year 2022 are we still using an analog mode for so much of our amateur communication?

FM was invented in the 1930s, which is ancient history from a technological point of view. It has served us well, but it is long past time to move to digital. Of course, we do have many handheld and mobile radios available that support digital voice (DV) modulation. In fact, we probably have too many digital formats to choose from, all incompatible, which has fragmented the market. The three dominant digital voice modes are D-STAR (first out of the chute), DMR (a commercial standard) and Fusion (Yaesu’s C4FM offering). I think these all have their advantages and disadvantages which attract various people to support one or more of them. However, none of them is dominant and universal, like FM. It is interesting that virtually all DV radios on VHF/UHF include analog FM because it is The Utility Mode, the fallback modulation that keeps us all compatible.

Universal Digital Voice

For this post, I am primarily looking at this from a SOTA and POTA perspective, which means simplex operation and not repeaters. (However, you could extend this idea to repeaters, too.) I am also not so concerned about keyboard modes, just DV plus some basic digital telemetry that goes with it. It can’t be too complex or it will not be fast and easy to use.

I propose a universal DV mode that is implemented in all VHF/UHF transceivers (think in terms of your typical handheld or mobile transceiver for 2m and 70cm). And yes, go ahead and also implement D-STAR, DMR, Fusion, or whatever, but give us a universal digital format that just works. The key idea is to have a digital least common denominator mode that replaces FM. This mode can be the defacto standard for “meet me on simplex” and become the Next Generation Utility Mode. How cool would it be to get on top of a summit and push the DV Call button and work stations on digital many miles away? The station’s callsign should be embedded in the digital stream along with location data (lat/lon or grid locator) and some user-defined fields ( SOTA reference or other information). This format should also have really good weak-signal performance, significantly better than FM, for when the signal-to-noise ratio is low. All the technology must be open, to encourage wide adoption, with no proprietary codecs or modulation schemes.

The technology for this already exists and it would not be difficult to implement. The real challenge is the lack of industry coordination and collaboration between amateur radio manufacturers. Unfortunately, I don’t see this changing any time soon.

That’s my thought for today. What do you think?

73 Bob K0NR

9 Replies to “Universal Digital Voice”

    • We both know like Digi devices you can easily create or make a small box to connect to any USB enabled mobile radio to use VHF/UHF/MW without dealing with those rigid Japanese engineers at Yaesu and Icom. Even the old Motorola phones had the direct connect radio 15 years ago.

      • Yes, there are cute little digital devices that can be added to a handheld or mobile radio, but none of them are standard enough or popular enough to be a universal mode. That is why FM still wins out.

  1. We really have never needed amateur radio to go digital because it has been a late adopter of all technologies. The kids aren’t interested in studying to take a test to be able to do anything from their smartphones that amateurs can. Eventually, simplex will become the future of analog VHF and UHF. All it will take is one EMP.

  2. Bob, I agree with you that Amateur Radio can and should do better. M17 Project now has some hardware https://m17project.org/get-started/hardware that implements their protocol. It’s not neat and integrated, but it works. You might want to consider the OpenRTX firmware installed on a portable radio. (There are some references that there are folks who will do the hardware mods and firmware for a modest fee.)

    For those of us that want to help you and others from home, Module 17 might work. If M17 made those available, I’d install it on one of my radios with flat audio I/O. I think you would need to declare an M17 calling frequency.

    I think what might be needed is for a US M17 User Group to coalesce, perhaps a Groups.io mailing list so we could converse and hash out some commonalities like calling frequencies.

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