AX.25

I discovering some ax.25 packet radio floating around on 145.010MHz. I connected my Btech APRS audio cable from computer headphone/mic to the Quansheng, and piped the audio into multimon:

$ pw-record --channels 1 --rate 22050 - | multimon-ng -t raw -a afsk1200 /dev/stdin

Here’s some of the traffic I decode:

  AFSK1200: fm AA3RG-7 to ID-0 UI^ pid=F0
  TheNet X-1J4  (PINEGV)
  AFSK1200: fm AA3RG-7 to N3FUD-7 RR4-
  AFSK1200: fm AA3RG-7 to N3FUD-7 RR4-
  AFSK1200: fm W3AVP-5 to ID-0 via AA3RG-7 UI^ pid=F0
  W3AVP Packet System - FN10xc
  W3AVP-5: New Holland Chat
  W3AVP-10: Winlink Gateway
  AFSK1200: fm AA3RG-7 to N3FUD-7 RR4-
  AFSK1200: fm W3HZU-0 to N3FUD-7 RR4-
  AFSK1200: fm W3HZU-0 to ID-0 UI^ pid=F0
  YORKPA:W3HZU  Connect W3HZU-1 BBS & W3HZU-11 CHAT
  AFSK1200: fm AA3RG-7 to N3OGS-7 DISC+
  AFSK1200: fm AA3RG-7 to N3OGS-7 UA-
  AFSK1200: fm AA3RG-7 to N3FUD-7 RR5-
  AFSK1200: fm W3HZU-0 to N3FUD-7 RR4-
  AFSK1200: fm N3DWB-0 to QRZ-0 via KA3TKW-0,PINEGV-0 UI^ pid=F0
  N3DWB JONESTOWN FN10SJ
  N3DWB-1 Mailbox
  AFSK1200: fm N3DWB-1 to MBX-0 via KA3TKW-0,PINEGV-0 UI^ pid=F0
  Mail for: None
  AFSK1200: fm AA3RG-7 to N3FUD-7 RR5-
  AFSK1200: fm W3HZU-0 to N3FUD-7 RR4-
  AFSK1200: fm AA3RG-7 to N3UOO-7 UA-
  AFSK1200: fm W3HZU-1 to WA3USG-1 via KA3TKW-0 SABM+
  AFSK1200: fm W3HZU-1 to WA3USG-1 via KA3TKW-0 SABM+
  AFSK1200: fm WA3USG-1 to W3HZU-1 via KA3TKW-0 UA-
  AFSK1200: fm WA3USG-1 to W3HZU-1 via KA3TKW-0 I00^ pid=F0
  [KPC3P-8.3-HM$]
  95529 BYTES AVAILABLE
  THERE IS 1 MESSAGE NUMBERED 13
  ENTER COMMAND:  B,J,K,L,R,S, or Help >
  AFSK1200: fm AA3RG-7 to N3FUD-7 RR5-
  AFSK1200: fm W3HZU-1 to WA3USG-1 via KA3TKW-0 I10+ pid=F0
  [BPQ-6.0.24.33-IHJM$]
  AFSK1200: fm W3HZU-1 to WA3USG-1 via KA3TKW-0 I10+ pid=F0
  [BPQ-6.0.24.33-IHJM$]

I need to find a terminal program for Android (BPQ Term?), and read more about the anatomy of an ax25 packet.

AllStarLink

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.

Next Firmware: F4HWN

Problem: AUBSUK multiple scan list

The scan lists aren’t combining correctly on AUBSUK firmware. It’s skipping entries based on ordering. I realized I was missing most of simplex channels, but seeing the GMRS channels, when I enabled my “simplex” scan list in combo with primary repeaters. There’s an existing issue logged, but it’s hard to describe and to reproduce, I think.

Trying the Next Firmware, F4HWN 3.7

F4HWN is available on GitHub. I loaded it on both radios in place of AUBSUK to see how I get along. I’ve found a few features I really like:

  • Scan on start: if it’s scanning when I switch it off, it’ll scanning when switched on.
  • 3 scan lists: 1, 2, 3, 123, 0, all
    • they don’t recombine as freely, but I have:
      • simplex, repeaters, satellites on 1
      • GMRS on 3
  • scan is just as fast as others, so we’ll see if it’s tolerable.
  • “main only” display is nice, much easier to read.
  • spectrum analyzer with scan range, but I can’t assign it to a button.
    • Fn-5 is only way to activate it.

I think the S-meter is calibrated much differently from AUBSUK, and other firmwares I’ve loaded, calibration for VHF/UHF vs HF, The S-meter seems to read higher than I expect with lots of S9+.

The spectrum analyzer with a range seems wonky at times: it may be scanning the entire range, but the graph doesn’t seem all there. I noticed it with the scan of 144MHz-148MHz.

F4HWN 3.3

I loaded F4HWN 3.3 onto my UV-K5 to have a look. It only has 3 scan lists, and it’s awkward to cycle through them. I found starting the spectrum analyzer to be cumbersome as well, since i couldn’t attach it to a long-press of a button. The single VFO view is pretty nice; it puts lots of nice info on the screen, and it’s big. Ultimately, I went right back to AubsUK for the scan features.

Tape Measure Yagi

There are easy instructions to build your own yagi on Instructables. I had just picked up some hose clamps and had the other necessary pieces: a broken tape measure and some 3/4-inch schedule 40 PVC and connectors; so I was ready to build.

The wiring on mine is held in place by the clamps and banana clip adapter. I always like those for prototyping. As directed, I tuned the antenna by moving radiators in and out and measuring with the NanoVNA.

The antenna is noticeably directional, so I can use it to find directions of signals. The S-meter and dB signal strength numbers on AUBS firmware make it easy to evaluate strength and direction.

I transmitted with it to the K3IR repeater as a test during a net.

Aubs Firmware

I’m trying out the Aubs 00.07 firmware on my Quansheng radios. It’s based on the latest egzumer, and so far has kept up-to-date, and it has its own plugin for Chirp.

It has some really cool features for scanning:

  • scan on start, a feature I requested of egzumer, but was denied by egzumer.
  • 10 scan lists. I organized mine as:
    • 1 = local repeaters and popular simplex
    • 2 = all simplex, Ham and GMRS
    • 3 = non-local repeaters and other listening
    • 4 = satellites
  • press * to lockout a frequency from scan.
  • fast scan like egzumer
  • frequency spectrum analyzer, but no memory spectrum analyzer like nunu.

This is my daily driver now on both my radios.

FM Bandstop Filter

I posted to Facebook and got lots of discussion about the FM bandstop filter. When I started adding better external antennas, I could reach further (tx and rx**, but I also found that some VHF frequencies got much worse. It turned out I was overloading the receiver with the strong FM broadcasts in my area and increased sensitivity of the better antenna. I found a bandstop filter helped bring back those signals I was losing. [Read More]

NUNU Firmware UV-K5 & K6

I’ve installed the NUNU fork of the egzumer firmware on the uv-k6. It has a cool channel spectrum analyzer for super-fast scanning that can see all the active channels at once in the graph. There’s no good way to proceed to the next channel, but that’s not a huge problem.

The firmware also includes some unneeded “NUNU” mesh messaging protocol.

Egzumer on UV-K5

I installed a new firmware, egzumer, on my Quansheng UV-K5. The firmware has some handy features:

  • It displays name and frequency at once
  • It leaves the backlight on all the time at a lower level