Radio and rails...

M0RVB

RF invasion

Something leaks here, not always, just sometimes when the autotuner has an issue. RF gets into the Bluetooth stuff in the Mac and it goes mad. The net result is the cursor moves very sporadically making it very hard to maneuver the cursor. In the past I have resorted to rebooting the Mac - switching Bluetooth off and on is a no-go because I only have a Bluetooth keyboard and mouse so I'd not be able to turn it back on. Helpfully, the current MacOS knows this and won't let me turn it off anyway. So I reboot. However, yesterday I had the other systems turned on with MMSSTV and wsjt-x running on them so rebooting the Mac would have been rather awkward given I use Barrier to control the other systems via the Mac. So a bit of searching turned up a simple console (terminal) command 'sudo pkill bluetoothd' which did the trick. Apple has info at https://discussions.apple.com/docs/DOC-250003311 One to remember but YMMV of course... also, serves me right for letting RF in the shack in the first place.

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M0RVB

70cm FT8

I managed one 70cm FT8 QSO today. I had the TS2000X on 70cm randomly and answered a CQ. That was around 50 miles out to the southwest across the Pennines, so not so bad for my loft 70cm Big Wheel and with the rig set to 10W. A little later I put out a CQ, no replies but it did indicate I was heard in Wales at 78 miles and Northern Ireland at 179 miles.

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M0RVB

"A man with two clocks..."

You know the saying, a man with a watch knows the time but a man with two watches has no clue. Well, my GPS clock plus 10MHz source has decided it no longer wants to be a clock. It was a nice idea, came as a kit of parts from three sources and worked well up to a point. But the GPS module always seemed a little deaf. I had it connected to one of those little magnetic pucks but it struggled, often loosing all sight of any satellites. I tried it on an external antenna (sat on the windowsill) and on the puck placed outside with no difference. With a splitter inline a Leo Bodnar unit was happy so I had to assume the antenna was fine. Anyway, it has spent all day with no satellites in view whereas the QRP Labs clock is fine as is the NPT server. So it has been switched off and assigned to the 'box of abandoned projects' where it resides, alone. (edit: that one is now outside in the workshop with a small GPS antenna on the workshop roof and is working just fine - except the LCD is very sluggish with…

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M0RVB

Railway homework

Another of my hobbies, if you can call it that is that I volunteer at a heritage railway in the Signal and Telegraph (S&T) department. We maintain the signalling along the 4.5 mile railway which includes three signal boxes and numerous signals, points and telephones. Occasionally I get homework. This week it is working out the resistance needed to drop the voltage across the track at one point to a level suitable to power a relay. This is for a track circuit, in the case in question across a set of points. With the track circuits we use the section of track concerned, which is isolated from the rest of the railway by insulated block joints separating the bits of rail, power is fed to the rails at one end and a relay is connected at the other. The voltage needs to be sufficient to keep the relay up and this indicates that there is no train on that section of rail. When a train is on that track the voltage is shorted out across the wheels and the relay drops to indicate the presence of a train. The relay concerned is similar to the one shown below and has…

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M0RVB

Bye bye Wordpress

So... Wordpress has gone to war it seems. Now I don't use WP Engine but moves like the current ones do make me worry about maintenance of Wordpress itself, especially as I run it on my own server. When I consider that along with the fact that there is a constant stream of hacking attempts against my server many of which are attempts to get into the Wordpress installation I had to re-think my use of it. To make matters worse since we got upgraded to FTTP I ditched my rented VPS and moved all of my IT stuff to here. So my Wordpress runs on a box downstairs and I would rather it did not become a doorway for tinkers to get in and tinker. Plus the fact that for my little blog a full installation of Wordpress and its associated mysql database, where every page is rendered after the data is fetched from the database server is rather wasteful on resources. Also the theme I used incorporated Google fonts and I then needed a plugin specifically to get rid of those fonts. I would rather not be the reason someone's browser connects to Google for anything. So here…

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