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!
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 https://ioclarity.ca/building-a-raspberry-pi-amprnet-ipip-gateway/. 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.
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…
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!
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.
Sources: https://austinsnerdythings.com/2021/04/19/microsecond-accurate-ntp-with-a-raspberry-pi-and-pps-gps/ https://www.jacobdeane.com/iot/2020/building-a-gps-based-time-server/
I now have an RSPdx which arrived today and connected it in the loft to a discone which was already there. I changed the o/s on my Pi 4 that runs an ADS-B receiver to the 64-bit flavour, reinstalled FR24feeder and installed SDRconnect. Running it as a server it communicates very nicely with SDRconnect on the Mac Mini. It will be interesting to watch this software as it develops.
One this was clear… the discone is useless! While I realise it is little use at HF it is pretty deaf thereafter. So I have moved the RSPdx down to the shack so it can be plugged into ‘proper’ antennas. It is currently pulling in 20m. Of course, my HF antenna is on a tuner so I need to tune it via one of the HF rigs and then swap leads to plug the SDR in, but that is not much of an issue because it is all done via the BNC patch panel. I also had it looking at 2m via the white stick in the loft.
My old RSP2 is destined to go into the garage with a couple of VLF antennas as it is far too electrically noisy in the house for that. More on that if I ever get round to it…
I have, more or less finished the shack reorganisation which took 4 days! There are still some audio leads to sort out and I plan to do some woodwork to mount the two HF transceivers together. But here it is…
It does surprise me how I created space out of the previous mess of wires. Now the radios and PCs are all in reach of each other, test gear is all in one place, and the Creed 75 teleprinter has joined the shack (pity it is not yet working…)
Of the 4 screens, the top two are on a Linux PC, the bottom left is Windows 10 and the bottom right is on a Mac mini. A bit of very useful software called ‘barrier’ allows theMac keyboard, mouse and trackpad to control all three systems. All audio is connected through a mixer (or will be once I add a couple more leads) which also provides inputs to the computers.
Now to mess it all up again… how long do you think?
Still sorting the shack out today, hopefully two more days and it’s done. Today’s task was to fit PoE HATs to the two Raspberry Pi systems that run things like Pi-Star, the ADSB grabber and HamClock. These were both Pi 3B’s which do not have the pins for PoE – the 3B+ or the 4 does.
So, first off, strip the cards out of the box. Not too bad. The first Pi 4 and its HAT was easy but the Pi Star one has the RF board. Installing the PoE HAT does not leave any of the Pi 4’s pins protruding. Fortunately I had a small stock of extenders, in fact, just enough. Not the neatest of constructions but it works.
One thing caught me out though. The Pi Star Pi gets a static IP address via DHCP. When it booted up it would not let me connect or get to the web interface. A scan of the network found it and only then did I remember that, of course changing the card means a new MAC address! Anyway, both cards now have their MAC addresses in pi-hole (even though the IP is static doing it that way makes pi-hole record their activity against the names) and the Pi Star one has been reconfigured with a static IP rather than DHCP.
In between various large-ish DIY projects that need to be sorted over the summer I took time out to begin to rearrange the shack. I really want to site the radios next to the screens for ease of use but with the four monitors I have too little horizontal space.
So I thought, if I had a longer support pole for one of the dual monitor stands I could put the other two above. I printed a test cylinder with a flange to see if I could make a coupling for the two poles and after using that to get the size right I printed a 100mm one. This coupled the two nicely but during test fitting the monitors it snapped. Serves me right – I had originally intended the 3D printed part to be a guide only with a metal clamp connecting the two support poles.
Anyway, Amazon had extension poles which are a lot cheaper than a 4-monitor stand (Plan B was to buy a 4-screen stand) which arrived today. Here, then, are 4 monitors all nestled together – well, sort of:
The Linux screens are across the top, Windows bottom left and Mac bottom right. I use the program ‘barrier’ to share the Mac keyboard, mouse and trackpad across the three systems so I only need toe Mac wireless business to control the lot. So far, so good.
Now to move the Linux PC and make a unit to hold the radios, tuner and Signalink boxes… that then leaves a nice corner for the spectrum analyser and other bits of gear there is currently no room for.
Fingers crossed…
