News items for tag hamradio - Koos van den Hout

2017-10-10 Plotting the number of contacts (again) 1 week ago
After working through the results of my participation in the Russian worldwide digimode contest 2017 I decided to run a graph again of contacts per month as I did in Februari 2017. And remember how I made those graphs this time and save it in a plot script. qsl count plot

And the plotscript:
set output "qslcount.png"
set terminal png size 440,300 fontscale 0.7
set timefmt "%Y-%m"
set xlabel "Month"
set ylabel "Number of contacts"
set xdata time
set style data lines
set xtics format "%b %Y" 
set xtics rotate
plot "dataset-qsocount" using 1:2 title "Contacts/Month"
The interesting peak in January 2017 is still visible, it was caused by two contests I participated in: the ARRL RTTY roundup 2017 and the UBA PSK63 prefix contest 2017.

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2017-10-09 I participated in the Russian worldwide Digimode contest 1 week ago
Past weekend was the Russian worldwide digimode contest edition 2017. I mounted the endfed antenna outside and participated when time was available.

Thinks went good in search and pounce mode, there were multiple instances of making more than one contact in the same minute according to the log. Calling cq gave less response but I also got some contacts logged that way.
Band  QSOs Dupes Points Mults
160      0     0      0     0
80       0     0      0     0
40      46     0    280    32
20      41     0    129    35
15       0     0      0     0
10       0     0      0     0
Total   87     0    409    67
Claimed score is 27403 points
Since I operated in more than one band and with power above QRP levels I entered in the SINGLE-OP ALL HIGH category.

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2017-09-25 I participated in the CQWW RTTY contest 2017 3 weeks ago
This weekend was the CQ WW RTTY Contest 2017. I participated when possible in an otherwise very filled weekend.

In the end I made 81 contacts, 32 on the 20 meter band and 49 on the 40 meter band. One station in the US, KI1G in the state of Rhode Island (a new state). And the counter of worked DXCC's went up one, so I was browsing the log trying to find out which was the new country and it turned out that I made the first contact with Luxembourgh, LX7X. I will put that call on the list for a QSL card.

Finishing the log took a while. I set fldigi to contest style "CQWW RTTY" and used that template to export the log. But the logged CQ zone and state did not show in the Cabrillo export. I had to do that all by hand. Next time prepare the macros to log this correctly!

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2017-09-14 A portable mast for outdoor operations 1 month 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 month 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 month 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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2017-09-06 A solar flare stopping skywave propagation completely 1 month 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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2017-08-28 I participated in the SCC RTTY 2017 contest from the radioclub location 1 month 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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2017-08-24 Operated outdoor portable at the location near Maartensdijk again 1 month 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 1 month 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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2017-08-22 New QSL cards ordered, again from LZ3HI 1 month ago
Almost two years after I ordered QSL cards for PD4KH they ran out. I had to print stickers with the PE4KH call sign for a while to update the cards.

PE4KH qsl card front PE4KH qsl card back Now I had time to make new cards and see what the options where. I promised myself nicer cards with not just the standard data but nice colour pictures on the front side so I looked at ideas, drew some things on paper and worked a few evenings in the Gimp to get the ideas into something that would survive being printed. I created files for printing at 600 dots per inch so there should be no strange printing artefacts.

Image credits:

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2017-07-24 Last night receiving ISS SSTV images 2 months ago
And a third night. I used the timed recording option of audacity, which in the current linux version does not offer the option to set in advance how to save the project. This time I 'only' recorded for 7 hours, and was able to save the project afterwards without needing a recover. But on reloading the saved project audacity complained about some internal error in it, and it still had the problem of assuming 44.1 kHz sampling while showing the project sample rate as 48 kHz. Anyway, images decoded from the audio and I even recieved a few new ones.

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2017-07-23 Another night of receiving ISS SSTV images 2 months ago
On the night from Friday to Saturday I had the whole setup ready to receive more ISS SSTV images. And nothing was received since I had the antenna unplugged during Friday because of thunderstorms and forgot to plug it back in.

So when I found that out I put a note on my desk with 'Antenna unplugged?' which can be a reminder to unplug it when I'm done or plug it in when I want to receive something.

ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image ISS SSTV image On the night from Saturday to Sunday I plugged the antenna in and let the whole setup run again like on the earlier run on Friday Received slow scan TV images from ISS while I was sleeping. To make sure I had the antenna plugged in I tuned to 145.750 MHz where I can hear a distant repeater faintly.

Again audacity hung after the recording, and this time on recovery it had some issues with the saved project. At first I could see and hear audio of SSTV passes but qsstv could not decode anything. In the waterfall display of qsstv it looked like the frequencies were too low. I had a thought that maybe something decided the samplerate was back to 44.1 kHz so I simply speeded the audio of an image pass up by 8.8435% and suddenly it decoded fine.

In the end I decoded 11 images from the ISS SSTV project. Numbers seen 8, 10, 9, 6, 7, 8, 6, 4, 5, 6.

And 2 images from nearby radio amateurs who weren't operating according to the bandplan... but at least did not interfere with the ISS SSTV transmissions.

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2017-07-21 Received slow scan TV images from ISS while I was sleeping 2 months ago
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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2017-07-16 Uploading FT8 contacts to eQSL 3 months ago
This evening I noticed incoming FT8 QSO's in eQSL, so the mode is now recognized there. But I needed to retry uploading all FT8 contacts to get them to upload. It took a bit of experimenting, but finally the right SQL command to mark the contacts as not uploaded was:
$ mysql -S /home/koos/.config/cqrlog/database/sock cqrlog002
mysql> update cqrlog_main set eqsl_qslsdate = NULL where mode='FT8';
Query OK, 24 rows affected (0.02 sec)
Rows matched: 26  Changed: 24  Warnings: 0
And now they are all uploaded.

That is about a week between first seeing mentions of FT8 in radio amateur news and the first confirmed contacts.

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2017-07-16 I participated in the DMC RTTY 2017 contest 3 months ago
Or maybe I should use the word 'played' again: 6 contacts. It was a weekend with not much time for radio and when that time did happen propagation wasn't cooperating very well. The advantage of contests is that there are a lot of stations who want to hear every other station, so I used the last 20 minutes of this contest just to answer a few calls and get in the log.

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2017-07-12 New digital mode for amateur radio FT8 3 months ago
This week there was a sudden 'buzz' about a new digital mode for amateur radio from Joe Taylor, K1JT. It's like JT65, with a very minimal exchange (callsign, locator, signal report) but with a lot faster timing: each turn is 15 seconds and from what I can see somewhat more than 13 seconds transmitting. I made the first few contacts today after downloading wsjtx from WSJTX-Development : Greg Beam as Ubuntu package.

Screenshot waterfall display WSJT-X with FT8 mode They are now in my log, but uploading to eQSL / Logbook of The World is not possible yet as 'FT8' is not seen as a valid mode yet. The solution for LoTW seems to be to change to 'DATA' but this solution does not work for eQSL. I'll have to upload those contacts later when the mode is recognized.

First contact was with IZ8GNR and I also had contacts with club members PA2RG and PD3RFR.

With JT65/JT9 I sometimes get distracted waiting 50 seconds before it's my turn to react again, with FT8 it's more high-speed work (somewhat less than 2 seconds to react to a CQ or an answer). WSJT-X now has an auto-sequence feature which will step through the exchange automatically.

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2017-07-09 I participated in the IARU HF Championship 2017 3 months ago
My activity in radio contesting has been in digital mode contests, with one exception in a mixed-mode contest where I also made some voice contacts: the ARI International DX Contest in 2016.

But this weekend I seriously entered the IARU HF Championship in 'phone' (speech) mode. I made 59 contacts, 50 on the 20 meter band and 9 on the 40 meter band. I managed to work a lot of the HQ stations I heard active for the various national radio clubs. I heard no serious DX, but the local noise at home is prohibitive for voice contacts anyway. My personal reason for entering this contest was reading about its role in the world radio team championship in the book Contact Sport: A Story of Champions, Airwaves, and a One-Day Race around the World by J.K. George.

Screenshot yfktest with large font I used yfktest for the contest logging and found the biggest fixed font I can use which makes the 25*80 xterm almost fill the entire screen. See the screenshot.

Claimed results according to yfktest:
Band    QSO    Qpts   Dupes   Mult1   Mult2
  20     50     112       0      23       0
  40      9      13       0       8       0
 ALL     58     124       1      31       0
 Total Score: 3,875

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2017-07-03 Reboots of the FT-857 radio 3 months ago
The last week I had a problem with the FT-857 radio rebooting when I started transmitting in digital radio modes (PSK31 or JT65). The reboot showed as the radio giving the standard beep and the display and backlight switching off and on. Searching for clues suggested that some form of radio frequency interference would probably be the source.

So I wondered what I changed recently around the radio and remembered I changed something in the power distribution to have connectors available for powering my SARK100 antenna analyzer with a 12 volt battery.

Reseating all those power connectors and fixing some wires seems to have stopped the problem.

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2017-06-18 I participated in the Ukranian DX Classic RTTY Contest 2017 4 months ago
I participated in the Ukranian DX Classic RTTY Contest 2017 this weekend. I prepared the antenna and the contestmacros Friday evening, but I knew most of Saturday afternoon and Sunday morning would be unavailable.

Local noise was bad, it seems interference from solar panels is on the rise and it was a quite sunny day.

On the other hand, there was a 10 meter band opening Sunday afternoon, giving me some new multipliers with 8 contacts on that band. But no serious DX in the whole contest, I just saw Eastern Europe and Asiatic Russia active, unlike when I participated in the Ukranian DX Classic RTTY contest 2016.

The end result is that I made 70 contacts in somewhat less than 6 hours of operating time. So I participated in the SINGLE-OP ALL 6-HOUR RTTY category.
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