So… the buck converter module arrived and I soldered it in and set the voltage to 3.8V. One of the voltages was wrong. It transpired that I had a resistor of the wrong value, not far out mind, just a few ohms… ok, 560K instead of 56K! Ahem. Right, fixed that and the voltages are all correct so the serit module got soldered in and the USB module fitted. It was now that I realised that one needs to first register on the VivaDATV forum for access before you can download the software. Yup, read everything first… Anyway, the pause allowed me time to go back to the workshop and add the resistor needed for the V0.8 and newer versions of the software. Did I mention reading everything first?
I got the software today and ran the test program. This came up with two errors to do with the USRC and LAV filters and fixed by running packages that come as part of the MiniTioune ZIP. And success, all tests passed.
I have a box on order but otherwise it’s a matter of testing on-air now, or testing using the feed from a satellite dish. But now it’s raining and the project QO100 dish is still in the workshop.
Typical! I finally made time today to build up the Minitiouner hardware (https://wiki.batc.org.uk/MiniTiouner_hardware_Version_2) which had been sitting in various bags in a tray for a year now. Everything went well (the PCB is very finely made) right up to installing the step down buck regulator of which I had two from eBay.
So… step down buck regulators… they were right here in the rubber component mat. Where is the rubber component mat. Yup, the workshop has been tidied up and rearranged twice since all the components arrived and for some unknown reason I put the darn buck regulators on the bench and not in the same tray as the rest of the bits. And they are now nowhere to be seen.
After ages of it sitting there taking up bench space and having been moved about the workshop 3 times I finally made time to check the output waveform from the 444 today. Seeing I have a nice new shiny ‘scope what better test? Failed miserably of course…
After 5 minutes reading the ‘scope manual (!) I can now capture the keyboard output from the 444 and apart from a lot of ringing it appears to be generating the correct codes and spacings. No surprises on the distortion given it is switching between + and – 80V in quick succession with no form of conditioning. But, given the teleprinter refuses to print the correct letter for the pressed key it does suggest this is down to adjustment in the receiving setup and not the keyboard transmitter. Here are the characters R and Y:
I also checked the output from the TDMS5BV which is creating a nice, usable stream. Here it is repeating the character R:
Now, feeding the stream of characters from the TDMS5BV into the 444 and checking what it is trying to print out is somewhat enlightening. Y comes out fine, but R comes out as G and I as P. When I checked the bits for R, adding bit 5 makes G; similarly from I to P. Y already has bit 5 set, so it looks like bit 5 is stuck on. I am going out on a limb somewhat here given the first 4 bits of the code appear ok to think this is more a mechanical issue rather than the receiver electromagnet.
Fiddling by hand (a very scientific application of slight finger pressure on the transfer levers) does turn a G into an R when the R key is pressed. Given the mechanical hypothesis it probably just needs a really good clean! Onwards…!
I finally decided to rebuild the shack PC given that just about everything was going daft. I suspect this is a result of various software installs while testing new stuff that were not fully deinstalled. Yeah I know I should test in a VM…
Anyway, a complete fresh install of Ubuntu 18.04 with it formatting the disk has got the PC back to normality. Almost. Networking works again with the inbuild (un)helpful config rather than me setting it up by hand each boot via a script. And I remembered to sort Gnome out so I can get the classic view rather than the daft dock setup.
But there are two oddities… first off, the rather annoying way the screen layout changes (un)helpfully (!) when you touch the to left corner with the mouse. This can be disabled but when done so the Applications menu – the leftmost top bar menu – is no longer accessible. No amount of permutations of the toggles via gnome-tweaks will sort that.
But more annoying I have lost almost all decode highlights in wsjt-x. The only ones that work are CQ, tx and my call, nothing else. I’ve tried every combination. It’s not wsjt-x (I installed a previous version just to check, same result) and I am rather stuck with that now. It will be something obvious but I just can’t see it… hmmm.
Propagation on 6m is fascinating at times. These past few days there has been a pipe between here and southern Spain, hopping over France with no French stations seen on FT8. It has appeared at various times through the day, and on occasion has been wider at the other end, extending in an arc to parts of Italy. My 6m bit of wet string in the loft is fairly level and runs east-west so perhaps it will favour Spain (whereas the 20m bit is practically an inverted Vee and covers generally well)
As I type this Spanish pipe has been shut off again but it has been there three days in a row at various times of day.
I have been looking for a frequency counter for some time now and split between buying a kit that goes well into microwaves or seeing what comes on eBay. Finally a decent range one was advertised and I won it; it arrived today.
This guy counts from 10Hz to 2.7Ghz and the reason I got something with this range is it will hopefully prove that I am at least outputting something from the Pluto when I finally get round to setting up my QO100 station. Otherwise it is generally useful. It has a 10MHz internal clock running from an oven-ready crystal (sorry, a crystal in an oven!) so there is scope for feeding in a GPSDO signal if needed, although for my purposes that is probably not a requirement. Thus far, for a quick check it reads test transmissions on 2m and 70cm from a handheld accurately.
I have a digital oscilloscope on order (and will then sell my two CRT based ‘scopes), I have power supplies (only to 30V DC though), so I just need a waveform generator for general messing about. Not sure I need any RF source as I can use the Pluto.
The Unión de Radioaficionados Españoles (URE) ran an event to commemorate the 95th anniversary of the IARU with was founded on 18th April 1925 – 18th April is also World Amateur Radio Day each year. It ran from the 15th to 30th April. I had to have a go! There were 10 callsigns of the form AMxWARD and 9 bands in use, from 160m thru 6m. And as you might imagine there are quite a few pileups. I only used FT8 with the occasional FT4 but the stations were active on SSB, CW and digi-modes (I spotted them on RTTY, PSK31, FT4 and FT8).
After I made sufficient contacts for the Silver award I was going to stop, but after a short breather decided to go for Gold, finally making that on the penultimate day. I made myself a personal target of at least one contact on all the bands I can operate on, so 40m thru 6m, but I never managed 12m due to pileups. I also never managed to get the 10th station – pskreporter showed that they were receiving me but again, the pileups.
While I came nowhere really on the ‘score board’ (apparently 251st in the UK) this event was a lot of fun, if actually quite hard at times. My bit of wet string in the loft clearly lets me down but then again I did see some relatively decent spots of my calls via pskreporter, just not quite when and where I needed them.
I did also manage a couple of contacts with another Spanish special event station as well as one contact with GB2ARD (just a few miles away), both operating for World Amateur Radio Day.
Of course, during all of this I was struggling with my possessed PC which almost floored my final contact for the Gold award, but after beating it into submission and leaving everything turned on for 3 days it worked out. Time to rip it apart.
This was awkward. I found some info on the Web where someone had used a USB to Ethernet adapter and a Y-splitter cable to connect their Pluto to their LAN. So I got the exact same bits off eBay. Nope, no go. I resorted to asking on the very helpful Facebook group and tried all the advice, for example powering it via the separate USB power socket, but still no go. So, a process of elimination – the USB adapter worked fine on the Mac so no issues there, nor with the CAT5 cabling in use. But I did not have a separate mini-USB to USB socket cable, only the splitter cable. Back to eBay…
A cable arrived today and the Pluto appears on the LAN just fine. So it’s the Y-splitter cable that is at fault. Not tested it yet but it’s only a couple of quid so no biggie. Serves me right for not keeping things simple and using a splitter.
Anyway, one step closer to my QO100 project! All I need now is a decent way to get Ethernet out to the workshop. I do need a LAN out there anyway, not just the house wifi, so either a cable or a wireless bridge.
So the Ethernet interface on the shack PC decided not to work at all today. It’s managed by the network-manager stuff so no ideas why it had decided to go funny. Actually, it has been off colour for a few weeks now as at boot it does not see the Internet i.e. it fails to find a route but does see locally.
Anyway, I’ve never liked network-manger, I would far rather get control of it all myself. I realise it’s there for a reason but I favour a more handraulic approach. After battling it into submission and removing it from the startup scripts editing /etc/networks/interfaces has cured its tantrum. For now anyway!
But I am wondering what is up with the PC now as USB failures yesterday and then a collapse of networking today… everything important is backed up so no worries there. However, I am not of the camp that these things fail slowly as I have had PCs running for years and years before. I may well use this as an excuse to get a midi-tower system I can dual boot (Windows and Linux) and get a couple of PCI cards into.
This morning the rig would not go into transmit via wsjt-x. It worked fine last night up to when everything was shut down and there were no changes to anything, hardware or software. Rebooting the PC made no difference. CAT control was working both ways and it was receiving FT8 fine. I noticed that transmitting would sometimes change the rig settings e.g. from data to non-data.
I tried the flrig / fldigi combination but transmitting via this messed the FT450D’s settings up in that it was rapidly triggering tx and the rig decided to engage its internal tuner.
Plugging the two USB connectors into the front USB sockets on the PC made it work but the transmit levels are mad – ALC is triggering and the rig does not generate any decent power with this turned down. ALC is on a knife-edge where it goes from very little power / no ALC via the SignaLink TX control to 50% ALC and proper power output with nothing in between. Fiddling with the audio settings on the PC and in wsjt-x makes little difference.
But changing the Mode to Data/Pkt in Settings -> Radio does improve the ALC business. This was set to None and I cannot remember if this is a change or not.
The audio settings via pavucontrol are set to 100% for the USB audio. This was 120% before as otherwise the rig would keep falling out of Tx on 40m. Wsjt-x’s tune function is holding up on 40m at 100% so there is a change there for no apparent reason.
All the PC USB ports are USB2.0 so there is no difference there. Trying a few CQs on 17m shows that FT8 is being received across Europe so it is all working. The same is true to 40m.
Weird. The only physical differences between it not working at all this morning and now are the two USB cables are plugged into the front sockets and the USB leads are away from the antenna coax. But the latter, i.e. the cable routing has always been along the same path as the coax and it has worked every day without issue.