More QO100 progress…

After ages I finally made a rain cover for the POTY and led cables into the garage. Big delay there because the garage was a tip. It still is a tip, but the mess has been rearranged so I have access to the air brick where the cables come in!

It’s nice that when they built the house in the 1930’s they put an air brick right there knowing it would be needed for a satellite dish…

The rain cover is made from a sheet of plastic that came out of a smashed LCD monitor. I bent it round a bit of 110mm drain pipe using a hot air gun. it didn’t quite come out as intended but it’s near enough. The front is from the same piece of plastic and is epoxy glued on – yes there is a gap where the glue was less gluey, I’ll fix that later. Nylon threaded bar and nuts hold it in place. And it rained an hour after I made it so it does actually work.

After all the messing about everything still works. There is a nice box on order to take the gubbins – ok, the Pluto, bias tee, Leo Bodnar GPSDO, power supplies, oh yes and the pre-amp and amp I have yet to build. I’ve got Ethernet into the garage and I have tested SDR Console over Ethernet to the Pluto and all seems to work ok.

More QO100 work

I finally mounted the dish. It’s been cluttering up the workshop for months now. My original plan was to mount it on a pole by the workshop which would have needed a concrete base and regular trimming of the apple tree and hedge. So, it’s mounted on the garage wall with a TK bracket.

Aligning it wasn’t too bad except I managed first to find the Astra satellite at 19.2 degrees thinking it was the one at 28.2. After I found the second one it was not too difficult to find a satellite carrying Qatar TV using the GTMedia V8. With bolts tightened a bit and after rigging all the gubbins up I found the beacon via an SDRPlay SDR and SDRUno but the levels were well down. The Pluto and SDR Console did a far better job so there will be some setting I overlooked. I copied a couple of QSOs but working outside on a Sunday with the whole estate doing gardening made it rather hard, even with headphones! Anyway, the Pluto is the one that will be used so good to see the whole RX chain working. I have some decent WF100 cable for the LNB feed but will need to make something up for the GPSDO feed.

Next step is to mount the Pluto, bias tee and PSUs inside the garage and use Ethernet back to the shack. There is a convenient air brick next to the ironmongery.

The POTY is back inside for now and I’ll need to make a rain cover too, but it feels like progress finally.

Minitioune progress

Well I finally got some WF100 cable (CT100 replacement) to get a feed from the now unused Astra dish to the shack. My remaining CT125 is about 10 feet long and would get me nowhere. So I can finally test the Minitiouner on air and it works. No luck with trying to receive GB3YT though, it should be close enough and I have a small 23cm Yagi but our neighbours house is in the way. I will have to go mobile one day and see if it works, which is going to be hard given the rather old Windows laptop has a battery that lasts about 5 minutes and the XYLs laptop is locked down to a work image so no installing Minitioune. Anyway, for now at least it all works. It could us a switch maybe to switch the 12V feed to the antenna socket on and off.

Yes it is indeed in a box. This must be the second project I ever built that ended up in an actual decent box looking finished.

QRP Labs CW transceiver

I finally got round to starting to build the QRP Labs CW txvr kit which I’ve had since the 2018 Hamfest. Well, no sense in rushing things. I mentioned before the quality of the kit and the really excellent documentation PDF. I think I’m up to page 25. The documentation is all step by step and easy to follow, with a drawing on each step showing what goes where.

The one I got is for 40m – the kit comes with a low pass filter and components specific to the band you request. Of course I do still need to learn Morse! That’s still on my list of things to do which includes finish the QO100 project which now has two more kits of parts to build, and read up on the full licence for when, hopefully they release the online exam.

Here is a shot of the wound components which, although time consuming was actually quite fun.

And finally the completed board with the LCD in place. I went through the alignment process which all went according to plan using the built-in menus. The first pic is of the board powered and aligned and the second a bit of CW decode but this is on an 11m wire dipole with no ATU.

It is possible to mount this in a case and there is a wiring diagram included showing what goes where etc. once the various components are taken off the board – or, rather, not put on the board in the first place. But I will keep mine skeletal, at least for now.

Wet string effect

My bit of wet string in the loft, or rather, my fan dipole has been doing quite well of late, albeit only on FT8 and FT4.

By fan dipole you are no doubt thinking of a dipole made up of several, i.e. more than two, dipoles cut to various bands and all terminated on one coax. Well, yes, but I only ever got round to making it for 20m and 6m. But even there it has been doing well these past few weeks with all of Europe in easy reach and forays into USA as far as the west coast, Canada, South America, the top of Africa and the Middle East, plus occasional contacts in Turkey, Russia, Oman and Kazakhstan. Not too bad at all given the 20m wires are far from straight, being bent at the ends to fit and not straight horizontally either. I mean it’s sort of an inverted vee with a level bit in the middle and does seem fairly omnidirectional, probably by accident but hey.

It will tune on all bands from 40m to 6m thanks to the YT-1200. Since I passed the Intermediate I’ve set the FT450D to 30W, the maximum for the tuner, but even before that as an M6 I had PSK QSOs as far as Chile and the Falkland Islands at the maximum permitted 10W, and goodness knows how little of that actually got out of the loft. And tonight a -16 FT8 report to central Brazil at over 5,500 miles.

I keep meaning to put up a random wire and a suitable un-un to see how much better an external antenna will be. No chance of a beam or anything excessive here as we stick out a bit and there would be complaints. But wires should be ok. Of course, the shack is in the spare bedroom, so upstairs and the other side of the house from where the wire would attach, so quite a run of coax…

MiniTioune software

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.

MiniTiouner hardware

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.

More on order from eBay… serves me right.

Edit: typical. So the new ones arrived and the unit is working. Today I found the ones I ordered previously inside the envelope that the PCB came in, clearly placed there by me so I would not lose them! I now have 5…

Creed 444 progress

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…!

More PC blues

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.

Spanish pipe

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.