By Dale L. Puckett, KØHYD
Digital radios – DMR, D-Star, YSF, P25, NXDN – pick your protocol poison. These new radios populate the amateur radio landscape. They make worldwide contacts possible to amateurs everywhere.
Repeaters worldwide communicate using the Internet, making this new medium possible. Unfortunately, few repeaters exist to support these new communication protocols.
In Kansas we seem to be stuck in an analog morass, tolerating the noise and excessive bandwidth. Where repeaters do exist, they are most often not connected to the Internet. This limits communication to a local area.
No worries! There is a solution.
Ingenious hams invented hotspots to solve this very problem. With a hotspot you can have your own personal “repeater” that connects you to hams around the world.
The first hotspots were either “sticks” or dongles that you plugged into your computer. The sticks used your computer’s microphone and speakers to communicate.
The dongles were digital access points that were miniature radios. You talked to them with your digital handheld or mobile radio.
The access points used software in your computer to connect the small radio to the Internet. This was often problematic because the computer often went to sleep. This caused the software to quit and disabled communication.
Hotspots today use their own dedicated computer to connect you to the Internet. Most use a Raspberry Pi computer and a “hat.” The hat is a small circuit board holding a miniature digital radio. These radios usually have a range of several hundred yards.
Hotspots have two components, hardware and software. I use a ZumSpot which contains a small hat riding on a Raspberry Pi Zero W. The W stands for wireless. This board gives you a way to talk to your LAN and the Internet. Both boards together fit in a small compact case. The combination is highly recommended.
Jim McLaughlin, KI6ZUM, designed the ZumSpot hardware. José “Andy” Uribe, CA6JAU, wrote its firmware. ZumSpot descends from the Multi-Mode Digital Voice Modem (MMDVM), created by Jonathan Naylor, G4KLX.
The software of choice today is Pi-Star. It delivers access to your mode of choice when paired with a hotspot like the ZumSpot.
The ZumSpot/Pi-Star combination can link to DV repeaters, DMR talk-groups and reflectors. It also links to D-Star reflectors, YSF rooms, and QuadNet Smart Groups. This will keep you busy for hours, if not days on end.
You’re sold! OK! Where to start?
The best source for the official ZumSpot hardware is Ham Radio Outlet. You can buy either a bare board or a kit.
I recommend the kit. If you are a true hardware guru with tiny hands, go for the bare board. The kit includes a Raspberry Pi Zero W and a microSD card preloaded with Pi-Star. For a compact and very neat installation I recommend a C4Lab case.
When you complete the assembly of the kit, it’s time to install the Pi-Star software. It sounds scary, but actually it’s very straightforward. First you flash the Pi-Star software into a microSD card. You’ll need a card with at least 8 GB.
Then, you boot up the Raspberry Pi and create a WiFi connection using the Pi-Star software. You do this by connecting to Pi-Star.setup on your web browser.
Once you have the WiFi connection you reboot the hotspot and login to Pi-Star.local with your web browser. Pi-Star then gives you all the web forms you need to configure every mode you want to operate.
It sounds complicated. It’s the exact opposite. You’ll find two excellent sources of step-by-step instructions. The best source depends on your learning style. If you would like to follow someone else going through the steps, go to YouTube and search for Pi-Star setup. If you prefer written step-by-step instructions, point your web browser to pi-star.hamnotes.com.
I was able to configure my ZumSpot for both D-Star and DMR in less than an hour. It was a blast!
A DMR repeater is coming to WARC sometime in the future. In the meantime, why wait? Get your own hotspot, an inexpensive DMR handheld and get on the air now.
It’s opportunities like these that get me excited about amateur radio.
Let me know what you would like to see next in an email to kØhyd@arrl.net. Until next month! 73 de KØHYD.