2017-12-02 Preparing gpredict for AO-91 Fox-1B RadFxSat 1 week ago
Although reports are showing up that AO-91 has the usual 'zoo' when it's over southern Europe I still want to prepare for making contacts on interesting passes. So I dove into adding satellite transponder details to Gpredict again. According to [amsat-bb] AMSAT-OSCAR 91 identified it is Norad object 43017. And when Nico Janssen finds a satellite using his methods of doppler-curve fitting it's a very good indication it's the right one. So time to create a .config/Gpredict/trsp/43017.trsp with the right frequencies and details:[Fox-1B trsp 67 Hz PL] UP_LOW=435250000 DOWN_LOW=145960000 MODE=FMNow to find a pass at a for me usable time.
2017-11-25 Portable operation close to my home 2 weeks ago
Today I had some time left and the choice was between staying at home and throwing out the endfed and making a lot of contacts in digital modes or going out and trying a nearby park and making a lot less contacts but learning about my options there. I chose the latter one: I loaded my gear in the bicycle trailer and cycled to a nearby park, just outside the city limits of Utrecht. I took the fiber mast and used two elastic straps to tie it to a parkbench. The effect was that the mast was slanted but using it with the wire of the endfed twisted around it the fiber mast stayed up fine without needing its guy wires. And I forgot to bring the tent pegs anyway so I was unable to guy the mast. I tried the endfed as a vertical with some slack at the bottom and the transformer at the bottom. This gave me a horrible standing wave ratio on 40 and 20 meters. I guess the endfed is only balanced when it is stretched. The quick fix was to add a common-mode choke in the coax to the radio. I also added a counterpoise wire to the earth of the endfed to be somewhat balanced again. On the 40 meter band reception was ok but I could not understand a lot of stations. On the 20 meter band there was local interference. In the end I logged one whole contact on the 40 meter band with an Italian special event station. He gave me a 4-4 report and I gave him a 5-9+. After a few tries I gave up making him log me as /portable so I logged it in my PE4KH log. The location is still within JO22NC so I logged in my home log. As soon as the sun set it started cooling down and the grass got wet and I went home. It's a nice location and quite reachable from home. It's 10 minutes cycling and in 10 minutes I had the mast and the radio set up.
2017-11-08 Trying to receive Fox-1A (AO85) telemetry 1 month ago
I decided to try to receive telemetry data from the Fox-1A (AO85) satellite to prepare for receiving telemetry from the new RadFxSat right after launch. The FoxTelem program is ready to receive data from all the Fox series satellites so this was a good way to test my receiving setup. This afternoon there was a reasonable pass so I decided to give it a try. With the FT-857D radio tuned to the downlink frequency 145.978 MHz in FM packet mode. While I did hear the conversations on the satellite in the noise the program did not seem to receive anything. And then I noticed the sound display in the program reacted strongly when I tapped the microphone connected to the mixing board. I chose the wrong audio device. I have two USB audio devices connected to the computer, one feeds audio from a mixing desk and one feeds audio from the radio. Normally I can keep them apart but FoxTelem was only showing one of them. The solution was to set FoxTelem to the audio device 'default' and use pavucontrol to switch the input of the application to the right USB audio device. But by the time I figured that out the satellite was already too far to receive any useful telemetry data. Time to find another nice pass with useful elevation (above 10 degrees) to try this again. And it's a good preparation for the launch of Fox-1B.
2017-11-07 Waiting for the launch of RadFxSat (Fox 1B) 1 month ago
The subset of radio amateurs that is interested in amateur satellites is waiting for the launch of RadFxSat / Fox 1B. The name 'RadFxSat' stands for 'Radiation Effects Satellite'. The primary mission is in cooperation with Vanderbilt University ISDE studying radiation effects on commercial off the shelf components. The amateur radio mission is a FM U/v repeater with CTCSS, which means it can be used by radio amateurs to make long distance contacts. As any new satellite, the first phase after launch is a lot of testing before any experiments or radio services are started. During the testing phase the satellite will transmit short radio messages (audio with data mixed in as low frequency tones) with telemetry data. By receiving the telemetry data and forwarding it to the operators radio amateurs can help the testing. This telemetry includes voltages and temperatures which allow the operator to find out if the satellite operates as designed and whether the power budget (generated power from solar panels minus used power) is good. To receive telemetry from the Fox series satellites and forward it a program has been developed named FoxTelem and I am glad to see a linux version is available. This allows me to receive the satellite unattended and forward the data. I will at least try to participate in the 'Launch and Early Orbit program' during the first few days. Current launch date is planned at November 14th. More information:
2017-10-30 I participated in the CQWW DX contest 1 month ago
This weekend was the CQ World Wide DX Contest. This is indeed another phone (voice) contest, so I connected headset, footswitch and the remote head of my radio. I had some time to participate on Sunday early afternoon and Sunday evening. On Sunday afternoon the logical band to try was 20 meters, on Sunday evening 40 meters. In the end I made 51 contacts. All I did was 'search and pounce', checking for stations calling CQ that I could understand good enough and transmit my call back to them in the hope they would hear me. Some stations had me on the first try, some took several tries and some never heard me. The DX that got away was a Kazakhstan station who could not decode my call even after several tries. I used the yfktest contest software for Linux again. This wasn't very hard as yfktest has a standard definition for the CQWW DX contest. I heard both serious contest stations and single operators just calling CQ on the air. Interesting was to work OH1LWZ/M who according to his qrz page is really contesting mobile from his car or bicycle. For next time I have to check the compression and gain settings for SSB on my Yaesu FT-857D radio when using the headset. Claimed results:Band QSO Qpts Dupes Countries Zones ------------------------------------------- 20 40 48 0 15 5 40 11 19 0 9 6 ------------------------------------------- ALL 51 67 0 24 11 =========================================== Total Score: 2,345A few times I heard the contest call PA0AA of my radio club who worked very hard to get the antenna at the club ready for contesting, but only in the background when I was trying other calls. It would have been nice to get them in the log.
2017-10-20 Testing the new fibermast from a remote location 1 month ago
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.Read the rest of Testing the new fibermast from a remote location
2017-10-10 Plotting the number of contacts (again) 2 months 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. 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.
2017-10-09 I participated in the Russian worldwide Digimode contest 2 months 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 pointsSince I operated in more than one band and with power above QRP levels I entered in the SINGLE-OP ALL HIGH category.
2017-09-25 I participated in the CQWW RTTY contest 2017 2 months 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!
2017-09-14 A portable mast for outdoor operations 2 months 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.
2017-09-08 I built a common mode choke 3 months 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.
2017-09-08 I finished the linked dipole and tested it 3 months 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.
2017-09-06 A solar flare stopping skywave propagation completely 3 months 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.
2017-08-28 I participated in the SCC RTTY 2017 contest from the radioclub location 3 months 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.Read the rest of I participated in the SCC RTTY 2017 contest from the radioclub location
2017-08-24 Operated outdoor portable at the location near Maartensdijk again 3 months 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.
2017-08-24 Uploading FT8 contacts to LoTW from CQRLOG 3 months 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: 0That's after trying most lotw related fields and values.
2017-08-22 New QSL cards ordered, again from LZ3HI 3 months 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. 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:
- License plate generated with Kenteken generator
- Dom tower Utrecht from Utrecht Center Central Houses Dom Dom Tower
- Shelf with radio, power supply: own picture, also available at Alan K205 power supply, tuner and radio | KvdHout on flickr
- Recumbent bicycle with radio on wooden table: own picture
2017-07-24 Last night receiving ISS SSTV images 4 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.
2017-07-23 Another night of receiving ISS SSTV images 4 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. 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.
2017-07-21 Received slow scan TV images from ISS while I was sleeping 4 months agoOlder news items for tag hamradio ⇒
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.