Radio and rails...

M0RVB

Stupid connectors

So, new TV, empty space in bedroom, TV point and Ethernet points nearby, all I had to do was finish the wiring (left unconnected as it was not needed 15 years ago!) and scan for channels. Simple. OK. So I had a splitter and then found a smaller one so used that. Stuck it to the wall in the airing cupboard, wired in the CT125 coming down from the loft and two TV coax runs to the two bedrooms, and connected the other end of the CT125 to the aerial distribution amp in the wiring closet. Turned the TV on and it began scanning. And found very little. Hmmm. Well, it found the HD channels but would not receive them. Out with the meter. Connectivity fine from the splitter to the TV, so blamed the splitter and wired in the larger one. Rescanned. Same thing. Got a barrel connector and bypassed the splitter. No difference. Went to the wiring closet and checked the connection there... which I had plugged into the DAB aerial feed input, rather than a TV output! Put the smaller splitter back in and fitted the cables again and all is well. Ugh.

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M0RVB

50MHz

I can see the fascination with the 6m band these past few days. Lots of sporadic activity waxing and waning. Bearing in mind all I have is a wire dipole in the loft running roughly east-west I see plenty of FT8 activity from Europe and sometimes the Middle East, plus almost copied some SSB this morning. Now it has drifted off with only a couple of strong EU stations left. For a week or so I've tended to leave the PC on running FT8 on 50.313 just to see how things go. It should be firing data off to PSKReporter.

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M0RVB

GNURadio fun...

I have a had a real hard time trying to get GNURadio installed. The distro failed every time when running gnuradio-companion. This isn’t GNURadio’s fault, it may well be because my Ubuntu desktop has been upgraded a few times via dist-upgrade without it being a fresh install. Perhaps there is some old crud left in there even though I tried my best to remove all old versions of GNURadio and associated files and folders. After constant errors no matter what I tried it seems that my Ubuntu 18.04 installation somehow grabs GNURadio compiled against a previous boost library 1.58. So I resorted to the pybombs method which has installed a functioning GNURadio-companion despite errors with apache-thrift. Sadly, when installing gr-iio via pybombs it failed, again seemingly trying to refer to boost 1.58, rather than the 1.65 that the 18.04 distro has. So… I purged libboost and grabbed the 1.58 code from sourceforge and set it off building. There are lots and lots of warnings but it did compile and install. Trying again to install gr-iio failed - it seemed to try to install boost itself and then whinged that the version is wrong. All deleted and purged again, still using…

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M0RVB

Project 444...

...the slowly ongoing saga. Typical. I wired up the 50-way D connector and connected it all up and ... nothing. On checking voltages half was missing, i.e. -80 was there but no +80. The barretter was open circuit on one side. Huh. A new barretter arrived via eBay and so I now have the PSU fully working. A quick check of the 444 showed it to be no better than before, which I'd expected but I really wanted the correct power supply to verify that. So I connected up the TDMS to send data to the 444 and with the keys set to SMSMS it reliably prints Y - pity that should be R! Fiddling with switch combinations is equally confusing. So, progress, of sorts. However, the TDMS itself needs work yet because the circular trace is far from a circle, or indeed not even close to anything which might be imagined to be circular.

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