Amateur radio ⁽²⁵⁶⁾

(updated) I finally had all the bits in one place to sort out the power supplies for my QO100 box. I managed to assemble the 'filtered S-band driver/amp' and the 'QO100 5W amp' kits from AMSAT UK and learned a lot about SMDs like (a) I don't like them (!) and (b) I find it far easier, being short sighted to just look up close than use magnifiers. Anyway, the kits both went together as planned and passed the basic test relating to current draw so I was hopeful that I had actually not managed to mess them up. I also had much fun assembling the LMR600 coax with memories of central heating installation! Finally, with a 12V PSU, a 12V to 5V module and as 12V to 24V module from eBay and tie wraps to hold stuff in place I managed to get volts where needed and gingerly turned it all on. The Pluto found the Ethernet, the GPSDO lit up and SDR Console found QO100. Nothing odd in that because it was all working before but is now assembled into a box. On the left (the door) are the two voltage converters and the GPSDO, and on the right the Pluto (LHS), the bias tee (central) and the 2.4Ghz amp (RHS) with the driver/amp above. The most awkward bit is the USB to Ethernet adapter. The LNB input, 25MHz output and the GPSDO input cables enter from underneath and go out to the dish via the white conduit, and the LMR600 enters through the side into a short piece of LMR195. There is a 12V PSU mounted on the outside of the door in a separate box. But does the transmit side work? That's all new. With a Windows laptop running SDR Console and the MacBook looking at the WebSDR both sitting on the freezer in the garage (so I could see if the QO100 box caught fire!!) I managed two very short test transmissions. It works! The audio was a bit naff but that is probably down to me not yet familiarising myself with SDR Console and using the mic in the laptop. So, after ages and ages of getting bits together and everything else getting in the way it's almost done. Signals are still down compared to other, more successful setups out there but at least now it seems all I need do is properly align the dish and sort the audio side out. And tidy the wiring. Oh yes, and sort out the GPSDO locking for the Pluto.

Had my first 70MHz FT8 QSO today, and I think the third anything on 4m because there's little activity here on FM and I only just got the transverter. There was a surprising spot at -23db and 1,443km to Poland but then an actual QSO with a Welsh station at 126km. So the converted 'FM radio' dipole in the loft works, as does the transverter.

Having a stupid morning. I wanted to check the output from my new transverter off air so wired up the RSP2 and CubicSDR on the Mac. I did all this yesterday when I first installed the transverter but wanted to check again now I've been stuffing FT8 out of it for a while. Good peak, nicely on frequency. No modulation! Ah. Ok, check everything. No change. Try QSYing and SSB. No modulation. Power off and on. Nope. Shout at the rig. No change. Set CubicSDR to SSB... ugh! All fine of course, it defaulted to FM... as it did yesterday but today I forgot!

I have an Anyone AT588 4m set but currently only a horizontal dipole in the loft made out of an old FM radio dipole. But I did want to go multimode, preferably without the expense of an IC7300. Anyway, I set my sights on a Spectrum Communications TRC4-10sL transverter and one turned up on eBay. It slotted in neatly between the FT450D and the YT1200 and with an AB antenna switch (I don't like these things but hey) it's all wired up. I am hoping for at least some FT8 activity but nothing yet. WSJT-X has a configuration where you enter an offset for given frequencies so for 70Mhz this is -42 (MHz), giving 28MHz = 70MHz, so WSJT-X sets the rig correctly. Now I just need to ensure I always set things up correctly, i.e. switch to B, transporter on, rig turned down to 5W. I usually run 30W which is the maximum the YT1200 will take in data mode. I can see me leaving the rig at 5W and wondering why no-one answers, but then again I may surprise myself at how far 5W will go - after all I managed the Falkland Islands and Cuba on a PSK mode on 10W before I passed the intermediate. But I suspect a large print crib sheet will be appearing next to the rig shortly because 30W into the transverter would be a very bad idea! Now I want one for 2m! Oh and the 588 will go in the car at some stage - I really must get mobile. Edit: no reception yet on FT8 or otherwise, but 4m was always a bit dead around here. But I was spotted on FT8 via pskreporter on the 27th at 90km N and +3db and on the 28th 120km SE and -17db, both by G stations, and on the 29th 126km SW and -19db by a GW. Both stations look to have decent antenna arrays but still not too bad for my bit of wet string here. Of course, with said bit of wet string they may well have replied but not been picked up here, evidenced by a couple of unlikely decodes at -24.

So, I’ve been running the Pluto over Ethernet to SDR Console on an old but still capable laptop just to see how it performs end to end. It clearly has issues! The first test was just pinging the Pluto from my Linux box with no SDR activity. This ran for almost 7 hours and dropped out in the early hours. Then I tested it with SDR Console running to see if it would last as long. 10 minutes! Another similar test lasted about 1h45. I added ferrites to all the power leads and this time it lasted about 3h30. Nothing at all scientific in these tests and I had already read up on Ethernet issues and the need to strap ground connections together internally but wanted to just see if the ferrites made any difference. Back to the workshop and I strapped the earth end of R58 to the earth end of D3 following the instructions found in this YouTube video at 7m36. The video describes that as the ‘simplified version’ - I’ve seen another more comprehensive one but this one is straightforward. There is a detailed investigation of the issue here and here. The Pluto held up running SDR Console looking at the lower beacon for 30 hours and is still running as I type this. I’ve not gone mad like running an electric drill next to the Pluto but so far, so good. Edit: SRD Console has been running for 47 hours now with no issues. I only stopped it because I need to sort out the PSUs and coax entry for the QO100 transceiver box in the garage.