Digital

Ham radio is a long hobby. I don’t really want to rag chew, so I started in FT8/FT4. I got lots of practice and learned about propagation with help of pskreporter and other operators. FT8/FT4 works with low power at home or portable.

I bridged into RTTY and PSK contesting for the next challenge and a bit of excitement interacting with another human keyboard-to-keyboard. I had to wait for contests for activity on RTTY or PSK.

Next, I’m learning CW, the original digital mode. It has the benefit of being common to see every day in POTA and in contests. CW is still low power and weak signal. It’s exciting to learn the skill to key and to copy. I can currently key, but I need assistance to copy with computer or radio.

Digital has been a fulfilling path through amateur radio so far.

I found the brand new wsjtx-improved available on my Debian unstable system. It’s the next beta plus some UI enhancements including filters, color, etc, better location labels.

This weekend was the FT Challenge.

I made about 112 contacts over 14 unique “letter grids”. I operated QRP (<5W), single operator, single radio. We scored points for each contact plus each 3000km distance on a contact, and the multiplier was that number of unique letter grids. I uploaded my logs, and it’ll probably be a while until I see an official score, but I figure I probably got about 2000 points.

I finally got my AllStarLink 3 node up and running. I had registered for a node number, and I had bought the pieces to have them ready to go. The little Pi Zero W boards I have wouldn’t boot, so I used a Pi 4 instead with the USB radio device.

Initial Installation on Pi 4

I started out with the official instructions:

• Downloaded the image for the Pi
• Installed the Pi Imager by deb file instead of just dding it to the device, since the imager conveniently allows pre-configuring:
  • user
  • locale
  • WiFi network

Configured the Cheap Ausinc UHF AllStar Radio Dongle

I purchased the hardware from Amazon a while ago. It has a USB-C port, and the cable is flipped for different modes:

• one way to program the frequency via USB serial
• other way to use the USB sound device for TX/RX The product description mentioned the different modes, but I didn’t recognize it. I learned about the flip from a video

I downloaded the srfrs.py Python script to the Pi, and used it to configure frequency and tone to protect default access to it:

./srfrs.py --port /dev/ttyUSB0 --frequency 438.1 --ctcss 94.8

Matthew, KC3WRY, suggested this frequency in the 70cm of the band. I was reading and wondering about 446.1 or 433 or so.

More Configuration and Confirmation

I followed another video for more configuration and confirmation of the settings from intro video.

I made another pass at web-based configs and asl-menu. I set it to be a SimpleUSB device in simplex mode, and I tuned the volume settings. I had no TX until I set “Change CTCSS From = no”. I don’t know what that setting does, but the tip came from the video. Then I could use the allmon3 web interface to connect up to Parrot+ node (55553) for testing, and it reported, “volume just about right.” I could connect and disconnect to nodes from the web interface. There are other commands in the web interface to say the time or id the node on demand.

I could send DTMF commands from my UV-K5 with the F4HWN firmware:

• * starts DTMF entry, PTT sends the codes.
• *1 <node number> disconnects from a node
• *2 <node number> connects to monitor another node
• *3 <node number> connects to transcieve to another node
• other scripts, like “disconnect all” don’t seem to work yet.

The W3GMS admins granted me access to connect my node to the repeater, so I’ll have a chance to try it out there. I was also able to connect to K3IR.

I further tested my AllStar node talkin to the 985 repeater. I discovered the bit of a delay caused my node to often skip a moment in the beginning of others’ transmissions, so I’d miss a second at the start. Also, since it’s simplex, I couldn’t throw any DTMF commands at it while the node is trasnmitting. I had to use the web interface to disconnect if others were talking at the same time.

I stumbled into a couple Olivia signals on 14071kHz, and on a good guess, I fired up fldigi, and I was able to decode them. They were Olivia-8/250 encoded. I found lots of good documents on Olivia to read some mmore about where they’re likely found.

PODXS070 Three-Day Weekend Contest kicked off on Thursday night. I made 8 contacts on 40m pretty early. Some of my contacts were bonus stations. It ultimately got overwhelming with at least 2 other digital contests going at the same time.

I used the fully-extended, large dipole kit and the RTL-SDR to successfully receive lots of 40m signals. It may have been especially busy, since it was Labor Day in the US and Canada. I found FT8 (40m and elsewhere) signals from St Lucia, Slovinia, South America, Cuba, and a little FT4 (40m).

I also found some BPSK31, RTTY/45, and still unidentified digital signals.

I had fldigi listening to SDR++ tuned to 7096kHz LSB for 20 minutes and decoded a couple different documents via differetn modes.

I also spun the dial to catch a couple other transmissions.