This is a little project I have been working on for fun. I had always been quite satisfied with System Fusion and Wires-X, but wanted to see what other modes were like. I know there are many out there who understand these FM digital concepts and terminology, but for those who may not, I will try to explain as I go along. Though I am no expert, I will do what I can and maybe pass along other links and references as I go.
How to Find and Connect
I’ve added that information to this page: K2AS XLX Reflector Info.
View the Dashboard
Go to http://k2as-ref.xyz
Background
Common Digital Voice Modes/Protocols
- System Fusion/C4FM
- DMR
- D-Star
- P25
- NXDN
- M17
These modes cannot directly communicate with radios that are using other modes. There are ways to make it happen with the help of a digital network.
Digital Networks
| MODE/Protocol | NETWORKS |
| System Fusion/C4FM | Wires-X, IMRS, YSF, YCS, FCS |
| DMR | Brandmeister, Free DMR, TGIF, System X, |
| D-Star | |
| P25 | |
| NXDN | |
| M17 |
In many cases, networks have been established to create and provide infrastructure to organize connectivity and enhance capabilities, such as bridging or cross-moding, in which different digital voice modes can communicate. Networks can be small or large, and are not necessarily required as most modes can still operate in an RF environment on simplex or via repeaters.
Reflectors, Rooms, Modules, and Talk Groups
First, some terminology. Reflectors, Rooms, Modules, and Talk Groups. These are similar to repeaters, as they are a way to go from one station to many stations. They are like a gathering point for multiple stations, but using the internet. Reflectors are used in D-Star, FCS and YSF. Rooms are used in System Fusion – Wires-X. Talk Groups are used in DMR and P25. Modules are used in XLX Reflectors, and are really just additional reflectors or rooms.
They all live somewhere on the internet. Some are on large or small servers, others run on a device in many ham shacks around the world.
The Top 3
I will just discuss the 3 most popular digital voice modes here. D-Star was the first and therefore the oldest. I was developed by Icom with the JARL in Japan. There are many users and repeaters out there. Slightly older technology, but probably not that big a factor. Kenwood has made a few D-Star radios.
DMR was developed for commercial applications, and has been adapted for ham radio. Probably the most complex system to learn, but many users around the world. Also, many networks have been developed for DMR. Several radio manufactures of DMR radios are out there making some lower cost options available ) Anytone, TYT, Retevis, Baefong, RadioOddity, Alinco, and others.
Yaesu System Fusion is definitely easier to learn than DMR. If you have a repeater in range, it really is plug and play. Several different radios are available from Yaesu, ranging from $180 – $500 or so. Even the HF/VHF FT-991A will do Fusion with some less features. There are many used Fusion radios on the market as well. System Fusion specs have been published, but no other manufacturers have taken the plunge. Wires-X is proprietary to Yaesu radios and one must get registered to access Wires-X directly. One could still communicate over Wires-X thru an already registered node. Fusion does not require multiple radios to operate a Wires-X node, but their cheapest radios won’t be capable. There more than one radio is common. I presently have 6. It is a sickness.
Hotspots
If you don’t have a repeater close by that functions in one of the digital modes, or you don’t want to buy one of Yaesu’s better radios. hotspots are the way to go. A hotspot usually contains a micro-computer such as a Raspberry Pi 2W and a Multimode Digital Voice Modem (MMDVM), or some equivalent hardware/software. A small 440Mhz transceiver is usually part of the MMDVM device to allow receiving from and transmitting to a radio such as an HT. They can run from $60 to $300, depending on how involved you want to get in getting it working. On all except the very high end, you likely will need some free software to run the hotspot (Pi-Star or WPSD). Some hotspots will also allow you to crossmode from one mode to another, such as use a System Fusion HT to talk thru the hotspot to a talk group on a DMR network or vice versa
What is an XLX Digital Multiprotocol Reflector?
A good question. I had heard about them, and they made it sound like some incredible magic was going on. I came to find out, there was often more to the story. XLX reflectors were born out of the D-Star world, but eventually came to support YSF, DMR, and other protocols. It is software that runs on a server that has 26 modules (rooms). It will take an audio stream from a station that is connected to one of the rooms, and pass that audio along to any and all stations connected to the same module.
In the case of YSF, it can transcode and be heard on DMR and vice versa. I am unclear at the moment on P25 and NXDN. A transcoding server can also be setup to transcode between any and all modes, and is definitely required for D-Star. (Multiple D-Star stations can still communicate when all connected to the same module without a transcoding server).
Modules can also be linked together. XLX servers can be linked together. DMR networks can be linked to an XLX server. Probably a lot of other capabilities that I am not aware of yet (documentation is sparse to say the least). Can’t complain for free.
How Does This Affect Our 2M Repeater?
By itself, nothing. The XLX Reflector has no direct impact on our repeater on its own. It communicates over the internet to YSF and DMR networks. Unless somebody bridges it.
There are a couple of ways. Bridging should only be done by the repeater trustee. Done incorrectly, it can cause major disruptions of systems, get a lot of hams mad, and likely get you banned from that network.
With that in mind, I have created a bridge between the XLX Reflector and Wires-X. But only to our Wires-X Room, #21704. This way, nobody should get hurt. But what it will allow, is (slightly) easier HT access to our repeater. It will require a DMR or Yaesu System Fusion HT (or mobile) and a hotspot. There are $90 Baefong DMR radios, and with a $60 hotspot, it is maybe half the cost of a Yaesu FTM-200 as a PDN node, or $180 FT-70 and a hotspot.
The bridge will not be online 24/7. We still are allowing stations to connect to the repeater via Wires-X and move to different rooms (when done for limited periods of time). Wires-X is always set to return to room #21704 after other rooms are disconnected. Since I usually shut down wires-X after 11:30PM, bridging won’t be available until the next morning. That may change, we’ll see.
Here is a block diagram of how the bridging and overall signal flow works.
Current State
With KA1CNFs help, it took several weeks to get this to a working state. Don’t ask. We have tested the reflector with DMR and YSF. We have been able to access the reflector via a hotspot and be heard on the W2XRX repeater. We have transmitted into the repeater with Fusion and be heard on a Fusion HT and a DMR HT via a hotspot. Callsigns are carrying thru to both systems.
So a better test is some real world use. I hope some people out there will give this system a try. We could have some growing pains, or it could fail spectacularly. It might also work well.
Future
Some type of net or roundtable. I’d rather not have another net about who mowed their grass today and what the temperature was. So I’d like to maybe focus on aspects of digital voice in the area. Maybe answer questions as much as possible. though as I said, I’m no expert. I do not particularly enjoy being a net control, though I have done it before, I don’t think I am very good at it. Finding people to help out would be a plus. But I think it is beneficial to spurring activity and maintaining it.
No other immediate plans. We might test P25 and see if it also transcodes as is. We are limited somewhat by the fact that there is no internet at the repeater site. I like that things are simple at the site. It lessens the number of trips out there.
M17 is an opensource project for a new digital voice protocol developed by hams for hams. D-Star and System Fusion were developed by hams and companies that sell equipment, which ended up helping segment the market by competing protocols. I could see M17 being a major player if done correctly.
Other connections to other systems? If anyone asked, I would certainly consider it without hesitation. I could request a connection from Brandmeister to XLX and/or Wires-X. I would need to study the requirements and ramifications. Plus they take many months to enable it.
If the system does not get a lot of use, I would likely scale back to a simple YSF reflector. That could still allow most users to access the Wires-X room. Though I’m not really sure if that is even a scale-back.
XARC Involvement
Just as the Wires-X node I have provided and managed since 2015, I am assuming the cost and effort in this project. Thanks to Steve KA1CNF for encouragement, advice, and testing.
