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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

2017-09-14 A portable mast for outdoor operations 1 week ago
As noted the last time I operated portable from an outdoor location it would be easier to deploy outside with a portable fiber mast. I borrowed a fiber mast for supporting an antenna earlier and it was really nice to have this option. It takes a bit of work to set it up, but it makes HF antenna work easy.

So I wanted one myself. The advice from fellow club members was to look at the offerings at DX-Wire which includes fiberglass telescopic poles and accessories to set them up. I ordered the 11,5m GRP pole "MIDI" complete with a spool of guying wire, a guying ring and other material to be able to set it up.

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2017-09-08 I built a common mode choke 1 week ago
After the problems with the laptop controlling the radio when I participated in the SCC RTTY contest 2017 I decided to build a common mode choke. This is a filter that should keep the radio frequency signals at the side of the antenna.

Based on the simple design with a piece of PVC pipe with 8 windings of Aircell-7 coax I still had lying around. The PVC pipe was donated by a fellow radio amateur who had it in his junkbox.

I drew a pencil line on the pipe, decided where to drill holes for the coax cable (using a 16 millimeter drill) and where to drill holes for tiewraps to hold the coax. After drilling the holes it was a matter of winding the coax correctly, mounting the cable with tiewraps and soldering the connectors to the cable.

In the first testing the filter worked fine, completely stopping the interference to the keyboard of my "shack computer" and even reducing incoming noise on the 10 meter band.
Common mode choke: materials - KvdHout on FlickrCommon mode choke: materials
Common mode choke: finding where to drill holes - KvdHout on FlickrCommon mode choke: finding where to drill holes
Common mode choke: holes drilled - KvdHout on FlickrCommon mode choke: holes drilled
Common mode choke: cable mounted - KvdHout on FlickrCommon mode choke: cable mounted
Common mode choke: connectors done - KvdHout on FlickrCommon mode choke: connectors done

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2017-09-08 I finished the linked dipole and tested it 1 week ago
I realized today I never wrote an article about finishing the linked dipole kit I bought a year ago and started making my own dipole from Linked dipole portable HF antenna kit.

I used the SARK100 antenna analyzer to test it on each band: first 15 meter, after that 20 meter and I finished with 40 meter. I did 15 and 20 meter on two separate meetings at my radio club and 40 meter in a park near our home. As mentioned by others you need to take the time to tune this antenna to the right length. Each band took me about 2 hours which turned out to be what I could do in one evening at the radio club.

The proof is always the first contact and that happened when I brought it on our holiday to Germany and Austria. The tree behind our tent at the campsite in Austria was not high enough to support the 40 meter length of the antenna but I just set it up for 20 meters and that worked fine. It's remarkable how forgiving this antenna is after tuning. I just set up something resembling an inverted V and my radio found it near perfect, very little reading on the SWR meter.

First completed contact was with a radio amateur at the same campsite so that wasn't very hard. I did hear a Dutch radio amateur using a serious amplifier to try to reach me but lacking output power he did not hear my answer.

Anyway, project officially finished.

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2017-09-08 VDSL tijdelijk met ADSL2 snelheid 1 week ago
Ik had een hik vandaag met de DSL verbinding en toen was ineens de snelheid 15 mbit downstream en 1.2 mbit upstream in plaats van 103 mbit downstream en 27 mbit upstream wat ik meestal gewend ben. Het leken wel ADSL2 snelheden. Ook met maar 512 carriers van de 4096 in gebruik. Toch was het DSL profiel nog wel 17a, wat een VDSL profiel is.

Na een tweede hik was de snelheid weer gewoon wat ik gewend was met vectored VDSL.

Update 2017-09-11: De snelheid blijft toch inzakken. De verbinding is nog stabiel maar ik verwacht eigenlijk problemen in de komende tijd. Het regent veel de laatste dagen dus het kan zijn dat er ergens water in de telefoonkabels terecht komt.

Update 2017-09-12: VDSL downstream week 20170912 En na een nieuwe hik is de snelheid weer terug. Het blijft magie, maar omdat het radiofrequenties zijn verwacht ik dit soort magie.

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2017-09-06 (I was reading about a solar flare maybe coming in the direction of earth on several places related to...) 2 weeks ago
Google+Koos van den Hout : I was reading about a solar flare maybe coming in the direction of earth on several places related to amateur radio (including this community).

By chance I had wsjt-x running decoding FT8 signals this morning but I was busy with other stuff. When I returned to the radio shack the last decode was at 11:55:30 UTC and not a single decode after that, and I just heard the local noise on the radio.
2017-09-06 A solar flare stopping skywave propagation completely 2 weeks ago
I was reading about a solar flare maybe coming in the direction of earth on several places related to amateur radio. Propagation via the ionosphere is affected by solar flares: a solar flare will change the ionization of the ionosphere seriously.

By chance I had wsjt-x running decoding FT8 signals this morning but I was busy with other stuff. When I returned to the radio shack the last decode was at 11:55:30 UTC and not a single decode after that, and just the local noise on the radio.

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2017-09-01 The right to be forgotten versus keeping history 2 weeks ago
For ages the whole 'right to be forgotten' issue was something happening to other people for me. The worst I do on my website is name spammers that keep sending me unsollicited e-mail.

This changed when I started playing with old files from BBS Koos z'n Doos including old BBS lists.

A few years after I started putting these on-line I received a request to remove a name from the lists. This person advertised running a 'hardcore sex' BBS in the 1990s. But in 2013 the rather unique name of this person showed up with a decent company and in this BBS list.

I could imagine that this person had no idea in the 1990s what someone might do years later with that information. At the same time it felt bad to 'change history'. Those were original files, it felt bad to change them. But after consideration I changed the name to spaces.

I also received notice from the google webmaster program that some search results are hidden on bbs.idefix.net. I have no idea which ones or what names I should mask.

The whole 'right to be forgotten' is a typical 'shades of gray' subject.

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2017-08-28 I participated in the SCC RTTY 2017 contest from the radioclub location 3 weeks ago
Again this year had the SCC RTTY contest in the same weekend as the barbeque of the radio club so the solution was to work in the contest from the location of the radio club. I set up with the endfed antenna in the available field.

That field is close to some houses so I had some interference. And the main problem was that the computer control between the laptop running fldigi (the contest logging software) and the radio regularly gave problems, usually leaving the radio in transmit mode. The laptop and the computer interface aren't shielded very well which is probably a reason, combined with the use of the endfed antenna which is known for causing interference since it's an asymmetric antenna.

In the end I made 53 contacts. Less than the number of contacts in previous SCC RTTY contest but I had limited time and local noise was higher than I expected. For a next time I am working on a common mode choke to limit interference to the computer and maybe some noise. And probably next time I contest at the radio club I will try to use a different antenna location.

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2017-08-25 (Cooling down after a nice barbecue) 3 weeks ago
Google+Koos van den Hout : Cooling down after a nice barbecue
2017-08-24 Operated outdoor portable at the location near Maartensdijk again 4 weeks ago
This morning I had some time and a good reason to leave the house. So I packed the radio, batteries and headphones and loaded all of it in the trailer of the recumbent and cycled to the bend in the road with a table and some trees where I operated portable before.

The local noise was very low again, about S1 on the 20 meter amateur band and about S4 on the 40 meter band. But conditions made the 20 meter band very quiet so I tried answering some calls on the 40 meter band first. In total I had 5 contacts, three of which were activations in the world wide flora and fauna program. Some of the contacts later in the morning were on the 20 meter band after it opened up.

All in all a nice way to spend the morning. Things noticed:
  • My newest lead-acid battery is failing already. It has trouble charging and when the charger thinks it is full it will drop output voltage way too fast. Time for a new battery with more capacity. 20 to 25 amp-hours would be a good value.
  • Getting a rope up in a tree is still annoying, I had to try way too many times. I am looking at fiber poles for portable operations. That would also mean there are possible locations for operating outdoor portable a lot closer to our home. Just a parkbench and some way to tie the fiber mast to something vertical is enough.

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2017-08-24 Uploading FT8 contacts to LoTW from CQRLOG 4 weeks ago
Other people from my radioclub were reporting they uploaded FT8 contacts to LoTW so I wanted to try this too. I uploaded earlier contacts as 'DATA' (and got some confirmations) but FT8 is the correct mode so I wanted to re-upload them.

After my earlier experiences uploading FT8 contacts to eQSL I expected some database work to be able to upload those contacts again. Finding the right field to set to the right value was a bit of work since I expected the approach to be similar but it wasn't. In the end:
$ mysql -S /home/koos/.config/cqrlog/database/sock cqrlog002
mysql> update cqrlog_main set lotw_qsls = '' where mode='FT8';
Query OK, 77 rows affected (0.01 sec)
Rows matched: 78  Changed: 77  Warnings: 0
That's after trying most lotw related fields and values.

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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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