Packet progress…

I actually achieved something. Makes a change!

At this stage I must state that I overlooked the fact I have an FTM100 and it has a suitable interface! Ok, no way I am going to fiddle soldering a 10-pin mini-DIN plug even if I had one, so I ordered a CT167 cable from  which arrived within two days. I already had a stock of D9 plugs. With the NinoTNC connected to the Windows PC the APRSIS32 software could send and receive APRS to/from my FT2D (no APRS activity round here other than a receive-only igate).

But packet was a tad more problematic. I wanted to use the Windows PC + Signalink + FT817 setup which means using QtSoundModem on the PC, but I also needed a program to talk to the TNC. QtTermTCP will via KISS but neither the Mac or Linux version had KISS anywhere to be seen, only AGW. And any mix of QtSoundModem and QtTermTCP on the Windows PC generally resulted in nothing talking to anything, which is probably my fault but it definitely got in the way.

So… I set up an old Pi 3B with the LinBPQ software, connected the NinoTNC / FMT100 to that and set up a test configuration. I then ran up QtSoundModem on the Windows PC talking to the FT817, and QtTermTCP on the Mac talking to the Windows QtSoundModem via AGW. And… nothing! The node sent broadcasts which were picked up by QtSoundModem etc. but connects to it all failed.

I noticed that if I sent APRS from the FT2D the OK LED on the TNC would light, but if I sent anything via QtSoundModem only the DCD flashed, no OK. Data issues then. It was then that I realised that in my earlier fiddling about with QtSoundModem I had all the various options in weird modes. Turning off FX25 and IL2P in the modem setting cured it (and no, I have no idea why I had them switched on!), and I could then connect. Success.

So, packet radio across the shack, using two radios, three computers and a NinoTNC.

Next steps… in theory anyway… I have a Tait TM8110 on order via eBay and a cable on order, I already have the programming lead and software. If all goes to plan I may even be able to build a packet node and get a NoV for it. As there is nothing at all round here then this may be a start if I can get others interested. I am to far away from other nodes in the progressive national packet network, but, early days…

Back on WordPress…

After a brief expedition to Write Freely I have moved back to WordPress. I had kept a copy of the old WordPress site so actually moving was not that bad other than adding in 4 or 5 posts and associated images…

Yet another project…

Note to self… stop collecting bits for projects and start building instead!

Just in, this PCB and chip for the TARPN NinoTNC. Described as a multi-speed, multi-protocol USB-KISS packet radio interface this comes as a very nicely made PCB and PIC plus a bill of parts complete with Mouser part numbers and a spreadsheet that loads into Mouser to make a complete order.

This will be a fun build.

The TARPN website also has full ordering and step by step construction details. Neat!

Packet radio

Messing around with packet today via the FT817 and Windows 10 PC. I’m getting used to two programs, WinRPR which supports Robust packet, and, of course, UZ7HO’s SoundModem.

There was a lot of APRS activity via RP on 10.1473MHz USB and it all decodes nicely in WinRPR.

Then on to SoundModem on 14.105MHz LSB (Network105). There were a few more decodes since I took the screenshot.

My next step is to find a client to tx APRS.


I have an allocation within 44net (aka AMPRnet) and so I set up a gateway based on a Raspberry Pi 4B – well, I had one unused one! My allocation is a /29, so 6 IP addresses. The Pi setup is the Pi 4, a PoE HAT, an Ethernet USB dongle for the second Ethernet interface, and a neat 3D printed case that I have used before and which has the height for the HAT.

Software-wise it’s just Raspberry Pi OS, plus a daemon called ampr-ripd which listens for gateway announcements and sorts out routing tables. My link is to the IPIP mesh so I am not doing BGP or anything fancy.

My initial experiment used the wifi interface and I could connect to 44net via the phone / wifi AP software running on the Pi. That worked ok but really I wanted to be able to connect a couple of systems and not bother with wifi. As I had an Ethernet dongle left over from the dismantled QO100 transceiver that did the job nicely. The plan is to connect this to a small network switch offering a couple of Ethernet ports to be used on 44net. So far, the only system connected is my ageing Samsung Netbook which is is horribly slow even with Lubuntu and has a weird screen xy format. But it works nicely using telnet to access a chatroom on 44net.

The basic configuration and ideas came from In particular, the scripts there set up the IPIP tunnel and add iptables rules.

The Pi has been set as the default DMZ host via the ISP broadband router (at which point it began to get hammered with ssh attempts which reminded me to disable password authentication!).

I have yet to get DNS names allocated so I cannot route over the wider Internet, not that this matters in particular as I can access other 44net services anyway.

RF interference…

Tidying up the whole shack make life easier to reach stuff but did not completely cure one issue, that of RF flying about the place and getting into things where it was not wanted.

I tried 10m this morning and two things happened. First, it set off the house alarm. Second, wsjt-x would not hold a tx cycle or tuning. The autotune was happy but that acts quickly. Using wsjt-x’s tuning for a few seconds, or transmitting a CQ and the FT450D would tx, then off, then try again etc. This has happened before.

First off, yes there is RF in the shack and it’s due to the rather naff antenna wire in the loft. I need to live with that until I get some wire in the air outside. And yes, I’ve been saying that for ages! But before it was really down to the mass of cables all entwined and those have been completely tidied up now. So I was rather annoyed that the same issue has returned.

And then I discovered that my attempts to dust round the desk had moved the serial cable between the FT450D and the Signalink and it was now laid across the antenna cable. Moving it cured the issue. For some reason when I fitted ferrites to that cable I only put one at the Signalink end, not the rig end. Fixed that too.

Some leads are still too long though. No sense really in tidying the place up but leaving long leads, so some soldering is planned…

Zigbee randomness

Recently the outside lights here decided to switch off at random intervals for no apparent reason. There are 5 different controllers, two being Zigbee bulbs and the others Zigbee switches. All use 2.4GHz. All had been running reliably for maybe a year. On/off cycles are controlled by scripts on the server as well as manually via an app.

In each case whichever set of lights had gone out did report as being off and would turn back on via the app. Some days there was no issue, on others at least one would go off at some point. The Zigbee bulbs never failed, just the switches.

There was no evidence of any commands being sent to turn the lights off, but there was the occasional error being reported. Rebooting the server made no difference. A power cycle of the server seems to have cured the issue so I am considering it likely to be the Zigbee transceiver itself.

This is now nagging at me to figure out what happened and presumably it will reoccur some time in the future. Too many other things to sort out though!

Shack networking

It’s surprising just how many things one gathers that need Ethernet. Having just made an NTP server out of a Raspberry Pi that took the last port in my 8+2 port PoE switch I needed more ports. The switch is a Netgear GS110TP, 8 Ethernet ports and up to two SFP modules for interlinking.

So I have added a second GS110TP linked to the original one via a short fibre lead and two SFP transceivers. The house now has 4 Ethernet switches, all Netgear, making 48 Ethernet ports in total but not all in use, plus 3 wifi access points, Netgear again and all PoE powered.

Actually I could have settled for a non-PoE switch as the additional one but this one came cheap, and new in box.

All the switches and access points do SNMP too, centrally monitored using MRTG. Why? Because they can!

A GPS based Raspberry Pi Stratum 1 NTP server

I decided to make my own Stratum 1 NTP server for the home. No, I don’t need the accuracy, but localising stuff like that is always interesting. So, I recently purchased an Uputronics GPS HAT from Pi Hut which is marked Raspberry Pi GPS+RTC Rev 6.4. It arrived next day along with some other bits. I also got another PoE HAT and already had a Pi 4. Raspbian installed on an SD card – this time I remembered to first set it up to work via ssh – and the Pi booted ok with the GPS board flashing it’s ‘time pulse’ LED once per second.

I followed instructions on the web, in particular from the two websites shown at the bottom of this post. Initial setting up of the Pi involves the use of raspi-config to stop the serial port login shell but leaving the port enabled, and disabling serial getty and bluetooth. At this point, doing cat /dev/ttyAMA0 should return data from the GPS receiver but all I got was garbled characters. More on that later.

The next step was to enable PPS support which involves modifications to /boot/config.txt and a module adding to /etc/modules, plus downloading pps-tools. Running sudo ppstest /dev/pps0 looked ok but again, more on that later.

Next was to install gpsd and modifying /etc/default/gpsd plus setting it up to run at boot time. After a reboot running sudo service gpsd status returned valid information.

The gpsd-clients package was installed which includes gpsmon. Running gpsmon showed that all was not well. It generated a few lines but nothing that meant any sense.

I then returned to sudo ppstest /dev/pps0 and noticed this time that all it was giving was timeouts. I may well have missed this in my haste earlier as it reports ok, but then gives timeouts. An, unfortunately not recorded web page suggested adding arm_64bit=0 to /boot/config.txt and after rebooting sudo ppstest /dev/pps0 now produced a valid line, once per second. Ok.

Retracing my steps I ran gpsmon again to take a closer look and noticed that in the few lines it managed to display was the entry ‘”bps”:9600’.

That was the lightbulb moment.

The GPS board defaults to 115200. Stopping gpsd and running minicom -b 115200 -o -D /dev/ttyAMA0 produced valid GPS data. Modifying /etc/default/gpsd to set the baud rate to 115200 (GPSD_OPTIONS=“-n -s 115200”) fixed the issue.

But, gpsmon still does not produce all the output that I had expected, in particular it does not populate the time and date fields. Running cgps does show valid information and suggests that all is well and there is something I am missing regarding gpsmon. At the end of the day it all appears to be working fine.

The next package installed was chrony. This all went to plan and running chronyc and its sources and sourcestats options showed valid data after the system had settled down for a couple of minutes after boot.

The final leg of this journey was to set up various systems to use the new NTP server. On the Pi systems this is typically done via /etc/systemd/timesyncd.conf and then restarting systemd-timesyncd; the Mac was done via System settings –> General –> Date & Time, and the various network switches and wi-fi APs each had their own way but each was obvious. Of course one thing to remember is these are all static systems that never leave the house. Setting a local IP into a mobile system would not be that great an idea.

The final thing that tripped me up was that in chronyc options such as clients would give an error. Running chronyc under sudo fixed those.

And there it is in a tall metal Pi case also from Pi Hut and rather unceremoniously chopped with some cutters to enable the SMA connector to fit. This case has plenty of vertical space for the Pi, the PoE HAT and the GPS HAT.




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