Clock

I finally have a UTC clock (it does other stuff too). This is a QRP Labs Clock built from a kit of parts plus a GPS receiver, also QRP Labs. Very simple to build. It runs from 5V (pity it’s not 12V but there you are) but I recently acquired a 5V linear PSU to run the three little LoRa boards rather than the 12V/USB charger I currently use. The kit is not yet finished – I need to attach the power switch and connect those two push buttons – but it’s a neat little thing in a nice case.

I was looking for a GPS locked UTC clock and recently built a kit which is also a 10MHz source and has a 10MHz OCXO to make a really useful device. That also has a clock display as well as other dispel modes such as satellites, locator and such but the clock is always about 1 second slow. Reading through the documentation from QRP Labs it transpires that this is because the 1PPS signal and the NMEA data can overlap, so the data stream from the GPS that shows date and time is not aligned to the PPS pulse which is the actual timestamp. Thus if you feed that data to a clock display it runs slow.

A GPS locked clock from QRP Labs showing the current date and time plus satellite statistics

(being lazy and saying GPS everywhere, I should really use GNSS!)

ISS SSTV event October 2024

So far I have received two complete but very noisy pictures from the current ISS SSTV event. The first was 11:37 UCT on 9/Oct/2024 and the second was at 13:12 on the same day. Both were as the ISS passed to the south of my location and right out over Germany, for the first picture and France for the second. I could hear SSTV signals as the ISS was approaching from the west but far too weak to decode. The transmission of the second image began as the ISS passed over the west coast just south of Wales and continued across the UK and across France. I can’t remember exactly. Anyway, here are the two pictures:

A noisy picture from the ISS SSTV event of October 2024.
A noisy picture from the ISS SSTV event of October 2024.

Both images were received on a 2m QFH antenna in the loft. While waiting for the signals to become strong enough I tried other antennas: the collinear heard very little, the big wheel did better but the QFH was superior.

Antenna moves

Another Hamfest is over… 160 mile round trip for me (ok, plus a diversion where I followed the signs to a service station which were ok until the last junction and I ended up on another motorway!!) but not a bad trip. Except for the roadworks on the A1… Anyway, a 6/4/2/70cm collinear came home with me and it is now installed in the loft replacing the existing 2/70cm one. Same cable etc. I also finished off the boarding over one bedroom – surprisingly the one where the antenna is and no, that’s not the reason for completing the boarding. Honest!

It has, as one may expect very little gain at 6m and 4m but replaces the 4m ground plane that I had and was rather in the way. Plus I never had any form of vertical for 6m.

I also managed to today the antennas up a bit. The 70cm big wheel is now no longer under the 2m big wheel and has its own place farther away. The 2m big wheel has moved so I can actually walk across the loft without needing to crawl under it.

I also recently acquired 2m and a 70cm QFH antennas from ft8.co.uk. These are really well made, being constructed from copper pipe and waterproofed. I will be experimenting with QFH antennas but wanted proper ones due to (a) being too lazy to build right now and (b) even when I do build one I need something to compare it to. Currently only the 70cm one in set up, in the loft again, and replacing a discone which was also in the way. This feeds a Cross Country Wireless HF-UHF antenna splitter and provides the antenna for three LoRa modules, one for TinyGS, one for radiosondes and one is a LoRa APRS iGate (RX only). The satellite reception report via the TinyGS console shows the antenna is working really well. My plan though is to replace this with a parasitic Lindenblad (seeing I am building one) and then actually use the two QFH antennas for satellite work. The only downside there is the need for more coax feeds into the shack from the hole in the ceiling, said hole already being full. But at some stage I need to enlarge it to run the LDF4-50A up for the QO100 dish once I move that from the garage wall. That will be a major tidying-up exercise!

Server moves

Up until now I have been running 3 Raspberry Pi 4 systems all held in a metal frame with fans which makes a nice neat setup. One Pi does the home automation, one runs pi-hole (really useful!), and one is a server and has an SSD attached. Not long ago while we were out of the country (of course) the website hosted by the server failed. I did not have remote ssh access set up nor a VPN for access. When we got back home the pi had lost the filesystem on the SSD. The disk was still mounted, but not accessible. Being a server all logging was on the SSD so no errors were caught. A reboot was the only way to cure it.

I thought it was a one off until it happened again, this time while I was nearby. After that our broadband was upgraded to FTTP and with PlusNet giving a fixed IP and no blocks I moved my production websites and email server across to the Pi, saving the rental of the VPS I had been using up until then. The cost of the VPS covered the annual cost of the broadband so worked out well.

Then the Pi lost the SSD twice in three days. This time had got worse because on reboot it did not start Apache or fail2ban, even though they both started fine by hand once I had realised. So something is wrong in the setup and I cannot find out what.

So I pressed an old Lenovo miniPC into action and rebuilt the server onto it. One thing I learned ages ago was to document everything that goes onto the server (and indeed all my other systems) so I can simply run through the list, add everything back in and copy /home across. Relatively QED.

But this time round something caught me out. After everything was moved across to the Lenovo and IP addresses swapped so it became the server web access was still going to the Pi. It transpired that the PlusNet broadband router associates the port forwarding with a physical device, not a IP address. Easy enough to sort out via web access to the broadband hub, but one more thing to remember (and duly documented!)

4 lines green

Slightly random… I have a Cisco SPA504G VoIP phone which I acquired ages ago and connected to Hamshack Hotline back when the UK still got 5 digit numbers.

The phone isn a 4-line one and subsequently I got a Hams over IP number for line 2, then an extended freedom network number on line 3. After that the phone sat for ages with only the three lines in green, waiting for a fourth.

I did consider buying a VoIP service to transfer our POTS number to once we upgraded to FTTP and lost the copper line. But then, all we used the landline phone for was ignoring junk calls, only ever making calls using my mobile phone which has free minutes and SMS, or using WhatsApp. So the landline went.

And still that fourth line was dark, just sitting there.

Along came CNet. I have had an interest in all things telephony and telegraphy from an early age. I always wanted a small mechanical PABX – I still don’t have one but I do have an eye out for a couple of old dial phones from my childhood. And that’s where the interest in CNet came from. Having investigated further I realised I could use that fourth line for access, and so it happened.

4 lines green…

A photo of a Cisco 504G VoIP phone's line indicators, all are lit green.

A new clock plus 10MHz reference GPSDO

I built a thing! This is a GPSDO using a PCB and kit of parts supplied by G8CUL and a OXCO from G1OGY. It uses a Jupiter GPS module which provides the PPS signal and a 10kHz output and the completed module provides 2x 10MHz and 1x 1MHz outputs. Although there are a number of such designs this one is nice in that it also has a display and shows the current date and time as UTC.

A GPSDO system based on a GPS module and OXCO module.

This was, I think my third SMD construction and certainly the Mose SMD devices including multi-legged chips. No issues in construction especially given the quality of the PCB that G8CUL had made.

The display on the GPSDO module showing the number of satellites and quality of signal.
The display on the GPSDO module showing the current date and UTC.

The backup battery is a CR2 3.3V type and helps with warm starting. As the regulator gets hot I managed to fit a heatsink between it and the rear of the case and hopefully this will sort out heat transfer, otherwise I may need to bolt another heatsink on the rear. Construction in a die cast box would have been better maybe but the blue/white box fits in with others in the shack, plus I had it already! The bezel is cut down from a 3D printed one from Printables.com designed specifically for the 2×16 LCD displays. The button – which is not the best but I had one etc. – selects the various displays which include date and time, satellites seen, latitude, longitude, altitude and QRA locator.

Middle of nowhere

So this is my day job – well, not exactly a job and only one day a week – volunteering at a heritage railway. And here we are in the middle of nowhere… good job it isn’t raining this time.

A railway line stretching off into the distance

Latest tooling addition

I had a number of Molex pins to wire up recently. To make things easier I decided to use some 4-core signal cable I had but found that the insulation is so poor at resisting heat that soldering the Molex pins was a non-starter as it always ended up with bare wires. Of course, Molex pins are designed to be crimped… so off to eBay.

The latest addition to my toolbox arrived in a couple of days and made the job a lot easier.

A ratchet crimping tool suitable for a variety of connectors including Molex pins.

Do I need two HF transceivers?

When I first got my foundation licence I was lucky in that a friend sold me a used FT450D at a seriously good price. Since then it has been in regular use. But now I also have the TS2000X I am somewhat torn. Currently the TS2000X is plugged into three antennas, the loft wire + tuner, and the loft 2m and 70cm big wheels. I had been using an FT817 for 2m and 70cm but that is now sat on the floor all disconnected. Poor thing.

But what to do with the FT450D… I do like the radio, it’s very easy to use, nice display etc. and quite compact. Ok, not compact like the ‘817 but it’s a 100W rig. But the TS2000X does everything I need in just one set, so do I sell the ‘450D? Decisions…

I mean, I don’t need both, I won’t use both together… or will I? Well, yes actually, I can run the ‘450D on HF and the ‘2000X on VHF, especially once I finally set up my external wire (the long one not the current short one). And the ‘450D is connected to the Linux box with the ‘2000X connected to Windows. So I can run both.

And I am reminded of those photos – you know the ones, someone in the US with a 100 foot workbench and several thousand transceivers (ok, a bit of an exaggeration there).

So I am keeping both. So there.

Now… the ‘2000X does FM on 2m and 70cm so another question is do I sell the FTM100DE? I mean, I rarely use C4FM. Nah, who started this selling question anyway?!

Moving stuff about

I am surprised that I actually managed to do something useful today. For a while now I have been meaning to put a Cross Country Wireless HF/VHF/UHF antenna splitter to use and today was the day. It is now sat upside down on the top shelf above the radios, fed from the discone in the loft and feeding two little LoRa modules, one for TinyGS and one receiving radiosondes. The TinyGS receiver had been running for some time sat in the loft and was previously the only thing connected to the discone. The radiosonde receiver had a 70cm ground plane in the shack and never received anything. Since reorganising the feed it has burst into life, rather surprisingly finding a balloon quite close to this QTH which was apparently launched from somewhere to the west of the Lake District but the data does not show the launch site. Looking at the altitude figure in the data I suspect it is already sat on the ground. Pity I cannot go out right now to see if I can find it.

Now, the cabling is RG58 and so not particularly good at UHF. The next step is to put a pre-amp next to the discone, and then to run some Ultraflex 10 instead of RG58. It’s only a few metres but every little helps.

TinyGS info can be found at https://tinygs.com

The software on the radiosonde receiver is rdzTTGOsonde and information can be found at https://sondehub.org/

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