2017-09-06 A solar flare stopping skywave propagation completely
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.
2017-02-23 Ok, not using the available wind meter readings in the neighbourhood
Today is very windy in the Netherlands, with storm with wind gusts of up to 65 km/h and average windspeed of 36 km/h. But the readings shown by the weather station readings shared in the neighbourhood show quite different values:2017-02-23 21:49:14 : HIDEKI Wind sensor Rolling Code: 15 Channel: 4 Battery: OK Temperature: 4.9 C Wind Strength: 15.29 km/h Direction: 337.5 °So I don't think those will help a lot for my Weather station Utrecht Overvecht.
2017-01-27 Nice neighbours sharing their weather readings
A posting about reading 433.920 MHz signals triggered the idea I had ages ago to decode those signals and see what weather stations are available nearby. The original posting 433,92Mhz ontvangen (Dutch) was about receiving remote controls (KlikAanKlikUit) and had a screenshot of some Linux software for receiving those signals but no name of the software (that would be useful information). But a simple google search found me rtl_433 on github which receives and decodes all kinds of signals on 433.922 MHz. I downloaded it on the raspberry pi for radio experiments, and it is working fine receiving weather information from probably nearby weather stations. At least one outside temperature and humidity sensor, one inside temperature and humidity and one wind and temperature sensor. This last one could be nice for my weather station!2017-01-27 21:00:27 : HIDEKI Wind sensor Rolling Code: 15 Channel: 4 Battery: OK Temperature: 3.6 C Wind Strength: 5.31 km/h Direction: 67.5 °and a rain sensor:2017-01-27 21:01:05 : HIDEKI Rain sensor Rolling Code: 0 Channel: 4 Battery: OK Rain: 648.2 mmThanks for sharing, neighbours!
2016-12-30 The weather confirms antenna theory
Last afternoon I hung up the endfed antenna outside to make some contacts on different radio bands. This morning I noticed it was all covered in frost due to a night with temperatures below freezing and with lots of mist. So I took the camera for some pictures of the frost on different parts of the antenna, gathered at flickr: img_3365 | Coil in endfed antenna with ice growth | Koos van den Hout | Flickr. After I took a set of pictures I started transmitting PSK31 on the 20 meter bands at 50 watts power. And my antenna theory tells me that the part of the antenna radiating the best is where the most current of the standing wave happens which is right after the transformer in an endfed antenna. Which I got confirmed: img_3380 | Endfed antenna with ice growth on transformer | Koos van den Hout | Flickr was taken before I transmitted and img_3378 | Result of using the enfed antenna: ice vaporized | Koos van den Hout | Flickr after. The ice is gone on the first part.
2016-06-23 A serious thunderstorm somewhat counted
Last night a serious lightning storm passed and it got counted, but clearly with the same problems in counting as seen before in counting thunderstorms from the shed while radio activity causes a lot higher counts. Looking at the graphs for thunderstorms counted from the attic before I was active on HF radio there is quite a difference in numbers. I think I want the lightning strikes counter back up in the attic but with a low-pass filter somehow to filter out false counts from amateur radio traffic.
2015-08-31 A serious thunderstorm counted
We finally had a serious thunderstorm last night, making us almost jump from the bed at one moment. And the lighting strike counter saw that thunderstorm nicely. It's quite clear the counts are lower now the sensor is closer to the ground. I'm not sure what to do to get a "good" count again. Last week I placed the 10/20/40m endfed antenna outside for part of the day and noticed that setup also influences the lightning detector in the shed. Raising the end of the antenna helped a bit, I noticed I can use the back gate of our house as the low end of the antenna.
2015-07-29 Finally a nearby thunderstorm
Finally a thunderstorm passed our house today, and it got counted on the lightning strike detector! The downside is that switching the light on in the shed a few times causes more 'hits'.
Lightning strikes counted today
2015-07-05 Moving the lightning detector to the shed and testing
I thought of this ages ago: Moving the lightning strike detector to the shed but only today got around to it because we had some serious chances of a thunderstorm earlier today which showed up on the lightning strike detector but the graph was completely screwed up again after I tried some psk31 digital mode transmissions on the 20 meter amateur band (14.000 to 14.250 MHz for me). So now it is in the shed. Moving it to a lower position does mean I will not get readings for thunderstorms as far away as I used to but I'd rather have usable readings at this moment. First tests with transmitting psk31/psk63 on 20 the meter amateur band after I changed it look like it doesn't count the transmissions anymore. Now to wait for the next good thunderstorm to see how that gets counted. Some blips are showing up. Update 2015-07-14: The first result seems to be that using the lights in the shed (tubelights with starters) shows up clearly. Using the radio still has no effect. I now await the first thunderstorm for more results. Update 2015-07-28: No thunderstorm has been reported by the KNMI weather institute thunderstorm archive within a short distance of my sensor. I guess the maximum range is quite limited now.
The last year in counted lightning strikes, showing clearly that I got active on 20meter psk31 in October 2014. The 'blips' before that are real thunderstorms.
2014-11-16 A wet roof and radio transmissions from the attic don't get along
The current rainy weather is reasonably deadly for any transmitting, given the report from Digital mode reception maps at pskreporter.info which states:Monitoring PD4KH (last heard 20 hrs ago).while I am quite sure I transmitted PSK31 CQs and answers more recently than that and the 10 meter band being open according to the same site. The attic dipole is right under the roof so any rain making the roof tiles wet is probably dampening the radio signals. This may get interesting when there is snow on the roof. I imagine some raised eyebrows when there is an antenna shaped hole in the snow on the roof.
2014-07-19 (#)Items with tag weather before 2014-07-19
The heat is on: the Weather station Utrecht Overvecht in our backyard is showing a temperature of 36.0 °C at the moment. Compared to official observations like the ones published at Actuele waarnemingen KNMI the temperature at my weather station is a few degrees too high. This can be explained by the fact that the sensor in the backyard is in an area between houses and the fact that we live in an area with a definite 'urban heat island' where temperatures are higher than the surrounding open country.