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Koos van den Hout

Welcome. This is my homepage where I write about my opinion, projects, things I note, things I try and other random stuff. Newsitems have tags for a bit of structure.

Latest news/thoughts/geeking/rants/notablog

2014-09-19 (The other side of network abuse: try to make it doable to report it to you!) 7 hours ago
Google+Koos van den Hout : The other side of network abuse: try to make it doable to report it to you!
2014-09-17 (#) 1 day ago
This evening I tried some amateur radio contacts in the 10 meter band in psk31 mode. And I got lucky, there were openings to North America, which was a new country for me and new distances!

Amateur radio psk31 mode in fldigi
Amateur radio psk31 mode in fldigi
I made psk31 contacts with KR4UA at a distance of 7069 kilometer, PA3FJE at a distance of 17 kilometer and W1AW/4 in North Carolina in the USA at a distance of 5731 kilometer. W1AW is the callsign of the US Amateur Radio Relay League which is currently 'on tour' of the US to celebrate the 100 years of the ARRL.

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2014-09-17 (Amusing moments in incident handling: After dealing with a compromised webserver and instructing the...) 1 day ago
Google+Koos van den Hout : Amusing moments in incident handling: After dealing with a compromised webserver and instructing the admins on research cleanup one came back with: "I registered for a workshop secure web programming to be held in November this morning, I did not know it was going to start today!"
2014-09-17 (#) 2 days ago
New messages in the wifi system logs, probably caused by the new TP-Link TL-WDR4300 access point:
[339796.577998] wlan0: associated
[339796.578154] cfg80211: Calling CRDA for country: NL
[339796.614689] cfg80211: Regulatory domain changed to country: NL
[339796.614711] cfg80211:  DFS Master region: ETSI
[339796.614722] cfg80211:   (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[339796.614739] cfg80211:   (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[339796.614754] cfg80211:   (5170000 KHz - 5330000 KHz @ 80000 KHz), (N/A, 2000 mBm)
[339796.614769] cfg80211:   (5490000 KHz - 5710000 KHz @ 80000 KHz), (N/A, 2700 mBm)
[339796.614785] cfg80211:   (57240000 KHz - 65880000 KHz @ 2160000 KHz), (N/A, 4000 mBm)
[339796.795070] wlan0: Limiting TX power to 23 (23 - 0) dBm as advertised by ..:..:..:..:..:..

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2014-09-14 (#) 5 days ago
Vandaag heb ik weer vanaf thuis de jaarlijkse landelijke ballonvossenjacht gevolgd. Hierbij wordt een peilbaken wat radio signalen uitzend aan een helium ballon opgelaten wat uiteindelijk ergens weer neerkomt, mensen kunnen dat signaal volgen en er zijn prijzen en eeuwige roem voor de eersten die aankomen bij de plek waar het geheel neerkomt.

De ballonvossenjacht is een van de bijzondere jaarlijkse evenementen voor radioamateurs. Dit jaar werd dit evenement voor de 36e keer georganiseerd, en voor mij was het de tweede keer dat ik het geheel gevolgd heb.

Eigenlijk is het in die 36 keer gegroeid tot een evenement wat multimediaal te noemen is. In ieder geval komen er allerlei aspecten van de radioamateur hobby aan te pas, zoals:
  • In ieder geval Amateur Radio Direction Finding (ARDF), de sonde zend een signaal uit wat met een peilontvanger en een richtantenne te localiseren is.
  • Amateur Televisie (ATV), de sonde heeft een kleine camera bij zich en zend dit uit en dit is te volgen via de PI6ATV repeater.
  • De sonde heeft ook een repeater aan boord zodat radioamateurs via die repeater verbindingen kunnen maken over langere afstanden.
  • Het controlecentrum is actief op twee repeaters in Nederland en op een korte golf frequentie. Heel de dag was het daar best leuk verbindingen maken maar het is ook een belangrijke manier van het controlecentrum om de radioamateurs die meedoen te bereiken.
Maar het evenement is eigenlijk multimediaal te noemen tegenwoordig, ook via andere wegen is het mee te beleven:
  • Via de ballonvossenjacht website en de ballonvossenjacht facebook community en de ballonvossenjacht twitter account worden ook alle statusberichten van het controlecentrum verspreid en kan het evenement op het web gevolgd worden.
  • De ATV repeater PI6ATV leverde ook een videostream via Internet met beelden van de ballon zelf, van het controlecentrum en van de hand van de held die in de Gerbrandytoren met een richtantenne zat om het signaal van de videozender in de ballon zo goed mogelijk op te vangen.
Mijn complimenten aan alle mensen 'achter' het evenement wat er vast meer zijn dan op het eerste gezicht lijkt. Er was een goed strakke regie zodat via alle communicatiemiddelen tegelijk hetzelfde status bericht over de voortgang de deur uit ging. Al met al een geslaagd evenement, ook voor mij als thuis meeluisteraar!

Update 2014-09-15: Direct na afloop is de GPS data ballonvossenjacht 2014 gepubliceerd. Daar heeft Remco PA4TW een mooie google maps visualisatie ballonvossenjacht 2014 van gemaakt. En met die .gpx file en GPS Visualizer kon ik weer een hoogteprofiel ballonvossenjacht 2014 maken (afstand versus hoogte). Het profiel 'tijd versus hoogte' was een stuk minder spannend: de ballon stijgt lineair op en in de daling is de invloed van de parachute zichtbaar.

Beelden bij deze post zijn uit de PI6ATV livestream en komen van Ballonvossenjacht 2014 - PA4TW met toestemming.

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2014-09-13 (The future in information distribution, as envisioned in 1980 from the US, when the teletext standard...) 6 days ago
Google+Koos van den Hout : The future in information distribution, as envisioned in 1980 from the US, when the teletext standard was growing in Europe. It has been tested in very limited areas in the US, but never grew beyond a test. Found via http://www.wired.com/2014/09/ceefax/
Ceefax is the 'brand name' used for the teletext service by the BBC in England.
2014-09-10 (I expected better from #wikipedia than an overlay ad. It may be a request for donations but it is still...) 1 week ago
Google+Koos van den Hout : I expected better from #wikipedia than an overlay ad. It may be a request for donations but it is still in the way. My reaction is the same as for any site that tries this on me: back button.
2014-09-06 (#) 1 week ago
I had a chance Thursday to listen to a pass of the AO-7 satellite. Passes of this satellite take longer than those of the SO-50 satellite. The AO-7 satellite has an inverting transponder for SSB operation so I have to search for downlink signals. I heard some: mostly CW (morse code) but even some weak SSB. To weak to make out callsigns (for me) so this will need practising too, just like I had to learn to hear callsigns on SO-50 in FM mode.

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2014-09-05 (#) 2 weeks ago
Oh and another interesting thing about the new TP-Link TL-WDR4300. It does IPv6. If I read the docs correctly it can do DHCP6 with prefix delegation or tunnels. It even gives itself an IPv6 address on the LAN side when that side runs address advertising. But ...
$ telnet -6 ap 80
Trying 2001:980:14ca:2:ea94:f6ff:fe91:21b3...
telnet: Unable to connect to remote host: Connection refused
the webinterface isn't available via IPv6. Nothing in the device is available via IPv6 according to nmap.

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2014-09-05 (#) 2 weeks ago
I am used to new access-points showing up at home which make us change the channel from time to time, but after getting hickups in youtube video on a tablet for the second time in a week I decided it was time to go dual-band and higher speeds. Good advice was to look at the TP-Link TL-WDR4300 which is dual-radio dual-band with 802.11n support with mimo. The advertised 750 megabit is when you add 802.11n at 300 megabit on 2.4 GHz and 802.11n at 450 megabit on 5 GHz. I'm not setting up extra wide channels on 2.4 GHz since it is busy enough, so I won't be seeing 300 megabit on 2.4 GHz anyway. I set up the network SSID and security on 5 GHz exactly the same as on 2.4 GHz so devices can switch automatically.

Week of wifi signal statistics showing access-point upgrade The weather station computer in the shed also measures wifi signal strength, the difference is clear so the TP-Link also has a stronger signal on 2.4 GHz. The wireless card in the weather station computer can do 5 GHz, but its antenna is tuned for 2.4 GHz and there are multiple walls between the access-point and that antenna.

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2014-09-03 (#) 2 weeks ago
I had an appointment today at a to me new address. I have an Android phone so I use the car navigation available from google. The 'Car' application has the (extra?) option to navigate to my next appointment, which made the fact the invitation had the right address information very useful. I used that and found the location fine. After I arrived people asked me if I had any trouble finding it since it is in a somewhat unusual location. I would have had more problems with a map!

HTC One Tip: How to use Car mode video explaining HTC Car mode and navigating to appointments.

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2014-09-02 (#) 2 weeks ago
Lag in DNS changes: I stopped hosting a domain for someone, the last 'regular' traffic was on 20 August 2012. But some web robots have a memory of their own, the last access by a search bot was 25 October 2013.

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2014-08-29 (#) 2 weeks ago
This evening I had a bit more luck with the 10 meter band dipole I made earlier. In the log this evening: 3 PSK31 QSOs with SQ2OIC in Poland and OM1AKD in the Slovak Republic and eQSL card from EA3HCE EA3HCE in Spain.

For me the first PSK31 QSOs and the first HF contacts.

PSK31 is a data mode, so I type stuff on the keyboard. The big advantage is I can do this all remote, controlling the PC and the radio from the couch in the living room.

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2014-08-28 (#) 3 weeks ago
Tuesday evening I was at the Veron region A08 club meeting and I watched as someone else played with the radio for a while. We noticed some interesting activity on the HF bands: people making DX contacts from as far as Costa Rica mixed with people clearly having a very local contact. People working distant stations (DX) usually just want to exchange callsigns and a signal report and maybe some niceties and get on to the next contact, people having a very local contact can chat on for a while talking about the weather, their car, the upcoming visit to the dentist and other items, usually called 'ragchew'. It's very funny to hear the different styles mixed.

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2014-08-27 (Did anybody record this contact? I missed it because of work and it seems it was a bit hard to receive...) 3 weeks ago
Google+Koos van den Hout : Did anybody record this contact? I missed it because of work and it seems it was a bit hard to receive this contact in the Netherlands (telebridge was via Italy) so a few fellow amateurs who I tried to get interested in space communications were a bit disappointed.
2014-08-25 (#) 3 weeks ago
I created the simplest possible antenna for use in the 10 meter HF bands: a dipole from recycled utp wire using some turns of coax as 'ugly balun'. I used this Wire antenna calculator to calculate the needed lengths. The choice for the 10 meter band was for a purely practical reason: this is the length I can put up under our roof easily. So I am trying PSK31 on the 10 meter band, around 28.120 MHz.

The first results the past evenings was a constant S6/S7 noise level, which leaves little space for other signals. And absolutely no response to my CQ calls.

But conditions can change, and this evening I am hearing some PSK31 traffic, and IZ3ZOW managed to copy my callsign in Italy but we couldn't make it a whole QSO. I also tried various setting for the noise reduction in the FT-857 radio to see whether that has a positive or negative influence on PSK31. I am seeing other traffic, so the 10 meter band must be opening a bit. I spotted OM0AST calling CQ from the Slovak Republic but he could not hear my signals.

Update: For me that opening didn't last longer than about 20 minutes.

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2014-08-23 (Bob Witte K0NR compares the Yaesu FT-817 with the Elecraft KX3 specifically for portable/SOTA operations...) 3 weeks ago
Google+Koos van den Hout : Bob Witte K0NR compares the Yaesu FT-817 with the Elecraft KX3 specifically for portable/SOTA operations. An interesting article, there is more to compare than just the price.
2014-08-21 (#) 4 weeks ago
In a few documents about the FM transponder on the SO-50 I noticed the use of the term PL tone where I expected the term CTCSS, for example in Operating SO-50 by Howard Long, G6LVB. I started wondering about the origins of PL tone and read the explanation on Continuous Tone-Coded Squelch System - en.wikipedia.org:
CTCSS is often called PL tone (for Private Line, a trademark of Motorola)

In amateur radio, the terms PL tone, PL and simply tone are still used somewhat commonly.
I'll keep calling it CTCSS.

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2014-08-21 (I haven't seen this mentioned in this group before, so I thought I'd mention it once: the fundraiser...) 4 weeks ago
Google+Koos van den Hout : I haven't seen this mentioned in this group before, so I thought I'd mention it once: the fundraiser to help Amsat launch the Fox-1C satellite which will include an FM transponder.

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The person

Father, cat owned/owner, Unix/Linux fan, Internet user, reader, recumbent byciclist, snowboarder, ipv6 fan. For those who don't speak Dutch: how to pronounce Koos van den Hout.

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Specialist information security at Utrecht University with a modern Profile page.

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Meningen zijn die van mezelf, wat ik schrijf is beschermd door auteursrecht. Sommige publicaties bevatten een expliciete vermelding dat ze ongevraagd gedeeld mogen worden.
My opinions are my own, what I write is protected by copyrights. Some publications contain an explicit license statement which allows sharing without asking permission.
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