News items for tag notablog - Koos van den Hout

2017-10-20 Testing the new fibermast from a remote location
I had time this week to test the fibermast I ordered and I wanted to do this at a location away from houses. Someone suggested the location 'Trintelhaven' which is a small harbour in the dike between Enkhuizen and Lelystad. This is a harbour of refuge in which ships on the Ijsselmeer can find a safe location to spend the night or wait out a storm.

Usually I do my outdoor radio activities at cycling distance, but this was an interesting location, I had the day available and I felt like going a bit further.

The Trintelhaven is originally an island created for the construction of the dike between Enkhuizen and Lelystad, which was going to form the 'Markerwaard'. But that plan was cancelled and now it is the 'Markermeer' (lake) with a new project to bring more life into it.

In the end I learned things about the new fiber mast, played radio, enjoyed the outdoors and had fun.
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2017-10-15 Getting to play VIC-20 games again
VIC-20 startscreen Ages ago my first homecomputer was a Commodore VIC-20. I did basic programming on it and played some games. I remember the game Centipede and loading games from audio cassette.

These days games seem to be enormously complex and expensive or filled with advertisments. I don't like these, the last time I seriously invested time in a game was Pinball Dreams.

I found out about the VIC-20 emulator xvic, part of the vice package. I even bought a cheap USB joystick to use. I never had a joystick with my VIC-20 so it was about time to get one. This joystick is a DragonRise Inc. Generic USB Joystick (yes, including the spaces) and I noticed today it wasn't working right: up and down on the joystick did not work. I found out eventually the left and right on the second stick mapped to up and down, thanks to a simple joystick tester from Joystick - Denialwiki in 7 lines of Basic.

Some searching found DragonRise USB Driver Issue - RetroPie which mentions this issue in hid-dr.ko happened in Linux 4.4 - 4.9.

I did not feel like going back to compiling my own kernels for this laptop, but there is a simple solution in Ubuntu 16.04: use hwe (hardware enablement) kernels. These seem to be aimed at the long term support server versions, but they fix my joystick problem and I can play centipede.

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2017-07-21 Received slow scan TV images from ISS while I was sleeping
I read about the current ARISS Celebrates it’s 20th Anniversary through SSTV Event and noticed the planned times weren't really compatible with my day/night cyclus. I know, as a hardcore radio amateur I should be up at the weirdest hours for rare events but I also like my sleep a lot and my wife really dislikes alarms at weird hours.

Automation to the rescue: I decided to record all of a night of ISS signals on the computer with audacity and decode images from it later. The computer adjusted the radio for doppler using gpredict. Since I don't have an automatic rotor for satellite antennas I used the VHF/UHF vertical. This may seem strange but the weakest signals from ISS are when it is right above the horizon (which is when the vertical has the best reception). And as noticed on earlier SSTV events that compared to other amateur satellites the ISS has a strong signal.

So I left it running for a night and checked the results afterwards. The result was a 9 hour recording and audacity decided to hang after stopping the recording. I made a backup copy of the audio data just to be safe and restarted audacity. Luckily it recovered the project fine after restarting.

With a recent version of qsstv I decoded the recorded audio and searched for ISS passes in the recording.

The result is 13 decodes in one night. It turns out it received audio from a number of low passes that I did not see in gpredict because I have gpredict set up to skip low passes (those that don't come above a 20 degree angle above the horizon). But the strong signals from ISS make those show up in my radio anyway.

Decoded and seen the numbers sofar: 11 (partially), 12, 9, 10, 9, 10, 9 (partially), 9, 7, 8.

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2017-01-04 Reviewing my 2016 amateur radio resolutions, and the new ones for 2017
Mobile radio for 2m/70cm in radio shack, CC-BY-SA Again on reddit /r/amateurradio there was a thread HNY! What are your 2017 Amateur Radio resolutions? so I checked the results for My 2016 Amateur Radio resolutions and thought about what I want to do in 2017 with amateur radio.

So, first to review what I hoped to do in 2016:
  • Pass the exam for the full license on 2 March
  • Participate in "Mills on the air" in May
Prepared, and failed: antenna wasn't working and by the time things were fixed the 40 meter band wasn't cooperating.
  • Making amateur satellite contacts when the weather permits
No contacts made, I got an antenna rotor and built a holder for the arrow antenna on that rotor, but I only used it to receive SSTV from the ISS.
  • Participate in a few digimode contests 'seriously' (preparing, using an outside antenna, optimizing score). Sofar I usuallly go 'oh there is a contest I'll throw in my call and see if I can score some points'
Done: did better in a few contests compared to my 2015 scores. Also worked on and improved my contest macros. I even did a little voice contesting.
  • Bring some radio stuff on summer holiday (a full license makes this possible in a lot more countries around here)
Brought the radio and an endfed antenna on a holiday in northern England. Found out the endfed gets into problems when cold (which was probably also the reason "Mills on the air" failed first). And by the time the weather was nice enough for the endfed to work again the battery of the radio was drained.

So, for 2017:

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2017-01-01 Leaped into 2017!
Jan  1 00:59:59 greenblatt kernel: [2538111.748198] Clock: inserting leap second 23:59:60 UTC
I usually distribute the leap second file to all servers I control to make sure there are no strange problems around it.

I wish everyone a good 2017!

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2016-12-05 NL-Alert? Doe mij voorlopig ook maar een echt luchtalarm
Vandaag was weer een NL-Alert controlebericht en als ik zo de geschiedenis inkijk van ontvangen infoberichten op mijn telefoontoestel denk ik dat het voorlopig niet verstandig is het 'ouderwetse' luchtalarm uit te schakelen.

Ik heb een dual-sim telefoon, die op de netwerken van Vodafone en T-mobile zit. Dus in theorie krijg ik 2 keer per jaar 2 berichten.

Uit de huidige geschiedenis:
  • 2015-12-07 12:00: om 12:01 ontvangen via t-mobile
  • 2016-06-06 12:00: niets ontvangen
  • 2016-12-05 12:00: om 12:03 ontvangen via vodafone
Op 2016-06-27 was er een echte reden tot nl-alert, en die heb ik via vodafone ontvangen.

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2015-07-24 Less flash but still playable audio
I like to sometimes add audio to items here on my homepage. In a format accessible for anyone with both download and play in browser options. Until now this was done using a flash-based player but lately flash has not been the secure option.

With the latest browsers it is quite possible to have an html5 audio player, but to keep it accessible for every visitor I also want to keep the flash audio player available. So I looked up how to do that and found Using HTML5 audio and video.

The linked audio is also available as attachments to the homepage RSS feed which is the standard for podcast feeds but since the recordings of satellite passes don't have an audio explanation or introduction they are not very usable as a podcast feed.

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2015-02-23 Preparing for upgrades and testing speed improvements for my homepage
As part of a needed upgrade on my homeserver I will also have to deal with Apache 2.4 and the changes needed there. Because some other things will change completely like asterisk I used an old server with comparable packages to do the same upgrades and test the results.

As keen visitors to my page may have noticed I am interested in the performance. This test-setup also gives me room to experiment with some possible new methods. I have to establish a baseline on that server first since it has different hardware.
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2014-11-24 Updates to my homepage
With some newsitems here on my homepage getting longer I started to feel the need to make a more blog-like format possible with items with an introduction and longer text. And titles here and there to give a better title to newsitems that deserve it. So some changes to the database format, support scripts and all the scripts generating pages.

The changes were big enough to update the version number so now it is 4.5.

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2014-03-07 (#)
Brilliant xkcd recently, number 1337: Hack - xkcd.

xkcd 1337 hack
Hackers (1995) - imdb movie database

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IPv6 check

Running test...
, reachable as PGP encrypted e-mail preferred. PGP key 5BA9 368B E6F3 34E4 local copy PGP key 5BA9 368B E6F3 34E4 via keyservers

Meningen zijn die van mezelf, wat ik schrijf is beschermd door auteursrecht. Sommige publicaties bevatten een expliciete vermelding dat ze ongevraagd gedeeld mogen worden.
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