Some AllStarLink sysops have expressed the desire to build an AllStarLink system on a modern Debian operating system. I took the time to document a working build process for the 020 Digital Multiprotocol Network and then Scott <KB2EAR> volunteered to create a shell script to automate the process. We are happy to share our work with the amateur radio community.
Please note that this process currently works only on the x86 architecture. It fails on a Raspberry Pi OS Buster system.
Hopefully this effort will fulfill a need for others in the AllStarLink community.
A comprehensive introduction to DMR is available to hams at no cost, thanks to the efforts of John Burningham <W2XAB>. His “Amateur Radio Guide to Digital Mobile Radio” won the 2016 Technical Achievement Award at Dayton Hamvention and the second edition was published in 2019. Even if you think you know how DMR works, this guide is full of useful information.
If your view of DMR is limited to the perspective of Pi-Star and Brandmeister or TGIF, this free book tells the rest of the story in its 27 pages. It is an easy read and will enhance your DMR knowledge.
I recently spoke with a fellow who was trying to use his hotspot on a frequency around 438 MHz. He wasn’t having much luck and with good reason. The MMDVM firmware blocks usage on all frequencies between 435 and 438 MHz. The block was implemented because 435-438 MHz is a suband used by the amateur satellite service and some amateurs noticed an increase of terrestrial interference with satellite communications.
Another ham that I spoke to is using a hotspot frequency that is also the input of several coordinated repeaters in my area. This is also not a good idea as it can also create interference, especially when operating a hotspot while mobile.
Here is my list of recommended simplex hotspot frequencies that is not likely to cause interference to other operators, repeaters, or satellites:
Most hams seem to set the admit criteria on their radios to Always for use with simplex hotspots. I strongly recommend that you use Channel Free instead to reduce the possibility of doubling.
Please wait one second after pressing PTT before speaking and wait one second after speaking to release PTT. This will ensure that there is no clipping of your first or last words.
All users of the 020 Network connections are required to have both a DMR ID and to be registered on the D-Star Gateway. It doesn’t matter if you don’t own a radio of that protocol. We are a multiprotocol system and by registering on both DMR and D-Star you are doing what needs to be done to be heard across all network connections.
Last August, I presented a solution for the “lost transmission” syndrome when using an MMDVM duplex hotspot. Several members of the 020 Digital Multiprotocol Group and I remain dissatisfied with our overall user experience. Granted, fewer transmissions are being lost than at first, but overall the number of transmissions during a longer QSO that fail to properly negotiate with the hotspot are higher than we’d like.
Earlier this week, 020 member Scott <KB2EAR> did some further digging and came up with aditional ideas found on the interwebs. I’ve taken these recommendations, added some others, and tested extensively. Here is my new set of recommendations for MMDVM duplex hotspot reliability when using DMR. This supersedes my article from August 29, 2019.
1) Update to the latest firmware.
2) Run the MMDVMcal procedure to minimize the BER
3) Set the MMDVMHost modem TXDelay=50
4) Set the MMDVMHost modem DMRTXLevel=55
5) Set the MMDVMHost DMR TXHang = 20
6) Turn off any mode other than DMR to avoid protocol scanning negotiation
I withdraw my earlier recommendation to reduce the DMR preamble. After much consideration, it seems to be unnecessary, with no clear benefit.
So far, using these setting on 2 different N5BOC duplex hotspots have yielded excellent results and reliability. Negotiation failures are now the rare exception. Tests were conducted with an Alinco DJ-MD5, a TYT MD-380, a CS-700 and a Hytera PD-365. Give these settings a try and let me know how they work for you.
There’s an exciting new development in the XLX reflector world. XLX reflectors now officially support Icom Terminal Mode. If you’re not familiar with terminal mode, it allows you to communicate with the DSTAR world via the internet from your radio. No separate hotspot or dongle is required and since RF is not used, no antenna either.
Terminal mode is supported by the newer Icom radios, including the IC-9700, ID-4100, and the Plus model HTs. If you have a radio that supports terminal mode and want to give it a try, set the host to xlx020.k2ie.net.
Thanks to Marius (YO2LOJ) for cooking up the code and submitting it to the xlxd project. It is great to see that the open source model is helping to advance digital amateur communications.
If you thought that the big amateur radio news of the day is that Andy Taylor has pushed Pi-Star 4.1.0 to general release, I’ll have some other news for you in a moment. But first things first.
If you’re already running a 4.1.0 RC (release candidate), please logon to your pi-star device via ssh and issue the following commands:
If you’re running a pre-4.1.0 system, you’ll need to:
Backup your configuration
Download the 4.1.0 image from the Pi-Star website
Unzip the downloaded file
Burn the .img file to an SD card
Copy the zip (don’t unzip) of your configuration backup to the SD card
Boot the new image
The bigger news today is that Andy has pushed the new G4KLX YSFGateway code into the Pi-Star image. This means that you can now directly connect to XLX020 and change reflector modules from your Fusion radio using Wires-X Passthrough commands.
You’ll have to enable the WiresX Passthrough slider on the Yaesu System Fusion Configuration section of the Pi-Star web gui. If you have an FT-70DR or another radio with an upper case only display, enable the UPPERCASE Hostfiles slider in the same section.
The process may vary a bit between radio models. The general idea is that you first initiate a Wires-X sequence to connect to XLX020. Next, you exit Wires-X mode and initiate another Wires-X sequence to connect to the module of your choice. If you just want to talk on module A, the 2nd connect is not necessary as you’ll default to module A.
Some radios, such as my FT-70DR, do not pull down a room list and you have to manually enter the module number. In that case, use 04001 for module A, 04002 for module B, and so on.
Have fun with this great new feature that makes the most of Pi-Star, XLX, and Yaesu Fusion.
Did you know that radio amateurs have our own paging network? Really, pagers, those slim devices that you carried on your belt back in the 1980s and 1990s. The devices with batteries that would last for weeks!
The Decentralized Amateur Paging Network was built by hams to provide the backend infrastructure to send messages to your personal amateur radio paging device. And if you’re running Pi-Star, you already have what is needed to turn your local hotspot into a POCSAG paging node on the DAPNET!
You also need need a pager. The AlphaPOC 602R seems to be a popular model that will work on the 70cm amateur band. The default paging frequency seems to be 439.9875 MHz and that is what Pi-Star will use unless you change it.
I wanted to play around with ham radio paging but, since I don’t have a ham radio pager available, I improvised. Isn’t that what amateur radio is all about? I wrote a python3 program to take inbound pages to my RIC (pager identification code) and send them to my email. I’ve shared the code on github and invite you to use it, comment, and contribute.
How can you use amateur radio paging? DX spots, APRS weather alerts, and solar activity are a few applications that come to mind. Share your ideas and be sure to send me a page via the us-nj transmitter group.