More ISS SSTV

I managed a couple of rather poor grabs from the ISS SSTV event of the 28th and 29th January. Nothing to write home about, my setup is not suitable being simply a loft mounted colinear. However, this one fragment was interesting because when received the ISS was over the middle of Poland.

Not too bad for around 800 miles or so. In fact, I received another fragment after this…

And two further grabs on the 29th, the first over the English channel and the second as it passed over Poland.

Snow effect

It’s snowing fairly heavily here today and I wondered what effect, if any this would have on my QO100 reception. Very little it seems. There is no loss of signal strength when viewing the lower beacon, but the noise floor has raised a little.

There’s not a great deal on the dish but then it’s pretty much vertical. There is a wedge of snow at the bottom of the POTY rain cover.

Clearing the snow off made no noticeable difference to the signal. It’s snowing less now and still nothing noticeable. I need to compare with a clear sky… which we had the next morning. There is actually very little difference, the noise floor appears better but it’s very hard to say by how much and indeed if this is even real. The signal strength appears very slightly better. Without proper measuring methods it seems the snow and ice made hardly any difference.

SSTV, DRM and QO100

A combination of things finally came together. I’ve never played with digital SSTV before, plus I had some time to fiddle about and wanted to see if I could decode some of the digital stuff from QO100. Finally, I received a couple of nice digital pictures of the Dakar rally from F6HA, neatly incorporating my previous main love of motorsport! My setup is far from perfect (read, a series of accidentally cobbled together bits): Windows 10 laptop running the excellent SDR Console and connected to my QO100 transceiver via Ethernet, audio mixer feeding from the laptop and to the Linux PC, and QSSTV on the Linux PC. There is a lot of noise in my QO100 setup that I need to figure out because it really messes up analogue SSTV and seems to have made these digital modes even more fiddly. This is probably not helped by the audio running round the shack. In an ideal world I’d have a decent Windows PC with two screens and a virtual cable. That needs to wait until we sort out what is to happen with an older PC desktop here as if it is to be replaced I will nab it and repurpose it as the shack PC, dual-booting Windows and Linux.

Next step will be to try and transmit, though I will start with analogue SSTV. And this will definitely wait until I get a Windows desktop because running transmit audio around the desk will make a further mess. KISS rules here.

More ISS SSTV captures

Two good captures early this morning, again on the FTM100DE and its co-linear. These are pictures 12 (received at 04:30 UTC) and 1 (04:47 UTC) of the series:

There was another pass just now and I wanted to try the FT450D plus its 144/28 transverter and loft mounted horizontal dipole. A bit disappointing but the pass was a lot further south and the pic was received with the ISS still over the Atlantic. Anyway, this is number 9 of the series, received at 09:33 UTC:

ISS SSTV event 2020

I am rather late for this event which runs from the 24th to 31st December 2020. Due to all manner of things, Christmas included, I only managed to have a go at receiving the images on the night of the 28th. The ISS pass was in the early hours so I just left things running. Among several partial images including identifiable bits of 3 of the 12 images I found this one:

Not too bad for a co-linear mounted inside the loft with a snow covered roof. I actually saw another image arriving from the ISS while approaching Spain at around 10:25 on the 29th.

Typically, in my rush last night to set everything up I forgot to tick the ‘Auto slant’ setting in QSSTV…

PiBox progress…

The PiBox is almost completed. It’s taken far too long due to all sorts of silly things like having to get fans because a dry run indicated the poor little boards were getting a bit hot, having to get bolts for the fans because I had none long enough, and having to get a connector for the 1-wire (actually 3 wires!) lead from the central heating sensors.

So, there is is. Two fans on the left, 5V PSU bottom right, gigabit Ethernet switch above that, then the Pi’s: top is the PiStar with the DVMega board which has coax to the rear panel and then a dummy load, middle is the ASD-B and central heating monitor Pi, and the bottom is a general purpose one with various bits on such as rtl_tcp. The lower two boards have USB-A sockets on the rear of the case for the two SDR sticks, one for the ADS-B antenna and one to attach to a Discone for general use.

But there is an issue. I had originally intended this to sit in the shack but those fans are just too annoying. Not loud, but constant. I suspect the box will end up in the loft. Or maybe a re-think. I may fiddle with running the fans from one (or two) of the Pi’s and set up some temperature control to turn them on and off. It may even be that I am rather too ‘sensitive’ to the temperature range as others seem happy running their boards a lot hotter than I do mine.

The full exam

Well I passed the full licence exam a couple of weeks ago now. The RSGB were particularly quick with things as Ofcom knew the Tuesday after my Friday exam, meaning I could chose a callsign, and the pass certificate arrived from the RSGB in the post the next day.

Here are a few notes while I remember in case they are useful to anyone. YMMV of course and different things work for different people, you need to do what works for you.

As you should know by now you need two cameras, the one on the laptop (or attached to a PC if that’s what you use) showing your face, plus another off to the side looking across. I used a MacBook and an iPhone as second camera. Positioning the phone was something I had thought out but got wrong on the day. I borrowed a phone stand for this but it proved impossible to get the angle right. This second camera needs to look across at you and the keyboard and screen and I ended up propping the phone against the stand having placed the stand on its side. It only fell over once which made me jump as I was deeply concentrating!

The Internet proved a bit of an issue as well due to some pauses. What would have helped was for me to make two WebEx calls to a friend to see what issues there might be. Also, having thought it through putting the phone on 4G could have made a difference, but there is only on bar of 4G in the room I was using. Anyway, I dashed out before the start of the test and grabbed a long Ethernet cable and plugged the MacBook in but there were still some short pauses, fortunately not sufficient to worry the invigilator.

Being mid-afternoon and approaching dusk I closed the curtains and put the lights on, put a sign on the door saying ‘keep out’, had two calculators (just in case), a table light, both the Mac and phone on charge, and a glass of water and two cough sweets. But that’s just me! However, I think it worth considering your environment – a view out to the street might be distracting, as might the sun if it tracks across and ends up in your eyes.

The TestReach software works well. You log in with the supplied credentials and can run through a demonstration beforehand. Do so, it shows you what to press etc. For the exam we started a WebEx conference 5 minutes beforehand and I used the phone to sweep the room. The invigilator then gave me the code to get into the test and I was away. I took time on each question, answered the ones I was sure of, and put an answer for and marked for review those I was not so sure about or didn’t know. Doing this meant that had I run out of time there would at least be an answer. I ended up flagging about 40%! Of those, I changed the answer on about 5 of them. In any event I passed, thankfully.

At the end of the test you have the option to download a PDF of the scores per section. You do not see the questions or answers but the sections and score. I had a few zeroes, areas I need to swot up on for the fact that, really I should know and I want to carry on learning. I did forget about this PDF of course, but I managed to log in again afterwards and download it.

Sources of advice were most welcome including the club I am a member of who held a few Q&A sessions on random test questions, and the Facebook group https://www.facebook.com/groups/fullradiolicense. I took some advice and did the two RSGB mock tests in the morning of the exam. I passed test 1 and failed test2! Anyway, I then dived into the manual cramming up on all the questions I got wrong. As others mentioned it did seem to me that the RSGB mock questions are actually harder than the real ones, but that is rather subjective.

Oh yes and if you are not a member of the RSGB do consider joining. I have been a member since 1975, in fact back then I joined as an associate because I was under 18. Yes you have to pay for the exam but do remember someone has given their time to sit and invigilate you for as long as it takes. And in my case I finished with just 20 minutes to spare.

So what now? For me, passing the full exam isn’t about extra power – for starters I’d set the roof alight as all the antennas are in the loft, and I can get most places on the 30W max that the YT1200 allows on digimodes. No, it’s two things, it’s the end of the journey (and the beginning of another) to a ‘final’ callsign that I can eventually work into a decent QSL card, and it’s the ability now to use the radios abroad, either under the CEPT agreement or a reciprocal or some other agreement. That last point is, sadly rather moot these days but hopefully we will be able to travel when things get better.

Good luck!

Raspberry Pi and SDRs

I had an idea that my RSP2 SDR could sit in the loft driven by a Pi in the shack. The Pi in question had DireWolf and a DVB-T stick watching APRS traffic. Ideal, I though. Hmmm.

I really thought this would be easy and a web search suggested that it should all work, my plan being to use the Pi to serve the SDR remotely from one of the laptops. 

My first attempt was to install a fresh Raspberry Pi OS and install SoapySDR and SoapySDRPlay. However, various bits of SoapySDR failed to compile due to some things not being found, even though I followed the instructions to the letter. A web search found only two identical but unanswered questions, so no help there.

More searches. SDRPlay have a useful looking image for the Pi where it will run in a number of modes, including soapy remote. This seemed just what I wanted. It all went in and the Pi throws open port 1234 which web searches indicated as the right thing for it to do.

However, SDRPlay refuses to play whatever I try. I have again followed what instructions I can find regarding remote operation, some of which point to the SoapySDR package so I downloaded those onto the Windows laptop. Again, no go. Trying a different mode results in – nothing.

There was also a claim that SDR Console will see a remote SDRPlay but it won’t for me and given my setup works really well for the Pluto / QO100 transceiver I have no intention fiddling with that further.

CubicSDR made promises as it at least mentioned Soapy Remote but will not find the Pi. Stuffing bits in by hand results in nothing.

Trying different modes in the SDRPlay Pi image yielded nothing further.

There seems no way to progress, so I have, for now at least given up and gone back to using the good old DVB-T dongle which at least has a simple plugin that works for data bits like APRS via DireWolf. At least it works.

Now, I’ve been fiddling about with software all my career and I would / should be able to figure this out. But thinking as a beginner all it would lead to is frustration. If this kind of facility is viable then more thought needs to go into documentation, simple step-by-step guides with problem solutions, and simple one-click installations rather than sending the user chasing around the globe finding bits that end up not working. Yes, I know the software is all provided as-is and someone has spent a lot of effort in building each bit for free. And yes, if I make the time to figure it out I will produce such a guide,  but don’t hold your breath as many other projects are calling for attention.

There is light at the end of the tunnel though (and it’s not just someone with a torch bringing more work!) – using the guide at https://www.2m0sql.com/2012/10/10/remote-sdr-using-raspberry-pi-rtl_tcp/ and SDR# on the Windows laptop at least the DVB-T dongle is working fine. Something to build on pending me sorting the SDRPlay out.

Of course, the nice thing about the Pi is it is so easy to copy a new image if you make a mess, and keep several SD cards with various ‘experiments’ on them.

FT450D MARS modification

In preparation for me receiving a full callsign (having just passed the full licence exam – yay!) I wanted to get the FT450D ready for 60m. Out of the box it comes with several pre-set frequencies that do not cover the available band slots and so the only recourse is to perform the MARS modification to the radio (aka ‘widebanding’). I uploaded the latest firmware first (v 244). Note that the firmware upload resets all the various settings so in my case I had to wind the power back down, set the CAT baud rate, and set the data type (‘D Type’) to USB.

I found two different sets of instructions on the Web, one referring to jumper JP4002 but another had a different number. However, one page had photos as well which tied in with what I could see. The instructions there are clear and are what I followed, the URL is https://radioamateur.us/ft-450d-mars-mod/

Following those instructions I took photos of each stage and have added a few notes below. Note that you do any modifications at your own risk and very probably voiding any warranty – I believe Yaesu will carry this modification out for you but this is just from what I ave read on the Web which may well be fake news!

The top and bottom cover need to be removed because you need to remove the front panel and this is held by the case screws. Each has 8 screws, 4 at the sides and 4 on top (or bottom). Note that the speaker is on the top cover and attached by a lead and plug to the front panel.

It was at this point that I got rid of the fluff which was everywhere!

The front panel is removed by easing off the 4 tabs that clip to the screw holes that can be seen at the bottom of each photo above. However, there is a ribbon cable that needs to be carefully removed – I found that it pulls out of the socket relatively easily (and went back similarly so). The socket can be seen on the right of the photo below.

There is a screen that needs to be removed in order to access the control board – this is in the radio and accessible after the front panel is removed. 6 screws hold it in place and I used a magnetised screwdriver here so as not to lose the things.

The photo above shows the control board. The front panel ribbon cable is to the left. The jumpers of interest are to the right of the largest chip. In my case the jumpers are all 0 ohm SMD resistors.

The instructions are to remove jumper JP4002. However, the labels do not actually seem to be next to the jumpers but given the photo on the other website I removed the same one, as seen above. https://radioamateur.us/ft-450d-mars-mod/ has a very helpful photo with tweezers pointing at the right one.

It was then just a matter of putting it all back together, remembering to carefully push the ribbon cable back into the front panel, and carefully easing the tab back into place to hold the panel to the body. Oh yes and not forgetting the speaker lead!

The next step requires some dexterity. One needs to press the IPO/ATT, NB and AGC buttons together and keep them pressed while turning the radio on. My method was rather crude, holding the radio with my left hand thumb above the power button, pressing each of the three buttons above making sure each clicked, then turning on with my thumb. The radio powered up and displayed SMADJO. Note that the photos below are each what happened in my case and I have no way to know if other radios show something different.

Next, you rotate the DSP/SEL knob counterclockwise until TYPE appears. No need to press the knob in first. I have no idea what ’38’ indicates.

Now press the F key briefly, just a quick click. This will be indicated by the usual F being displayed. The instructions do not show what the ‘c’ indicates, but see below as this changes.

Then, press NB – again just a click. The upper left segment of the currently illuminated frequency digit lights, changing it from a ‘c’ to a ‘t’.

The final step is to press and hold the F key for at least 3 seconds after which there will be a long bleep and the radio will reboot. This is, at least how it worked for me.

One final note. The websites I found list the modification as 1.8 to 30MHz and I was worried that it may somehow knock out 50MHz – but it still works, in my case anyway! In fact, the radio now seems to tune from 0 right up to 56MHz but not cleanly. I found that tuning from 29.999 took it back to 29 unless the MHz step is set (by pressing Dsp/Sel and rotating to select MHz) one can get to 32.999. Pressing Band to get to 50MHz permits tuning, again via the MHz selection, from 33 to 56MHz. YMMV!