New Year 2020: Excellent inversion over Poland

Ten wpis jest dostępny także w języku polskim: Nowy Rok 2020: Rekordowa inwersja nad Polską

This year’s winter in Poland has been very mild so far and it does not resemble this season in our country at all. In fact, it is more like late autumn with possible light frosts. The forecasts for January are still in line with current weather, so this month will be definitely warmer than average. Starting from the end of December 2019, subsequent high pressure systems began to move to Poland. Such weather favors good propagation conditions, which can significantly increase the range of radio emissions. An inversion in the troposphere can enhance the reception within a wide frequency range, starting from the lower VHF (typically 50-70 MHz), through broadcast radio, television, microwaves and finally even… optical waves.

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Nowy Rok 2020: Rekordowa inwersja nad Polską

This post is also available in English language: New Year 2020: Excellent inversion over Poland

Tegoroczna zima wcale nie przypomina tej pory roku w naszym kraju. W rzeczywistości nadal trwa późna jesień z możliwymi słabymi przymrozkami. Obecne prognozy nie pozostawiają złudzeń i w większości styczeń ma być bardzo łagodny. Od końcówki grudnia 2019 roku z zachodu zaczęły nadciągać nad Polskę kolejne wyże. Taka pogoda sprzyja podwyższonej propagacji, która potrafi w znaczny sposób zwiększyć zasięg emisji radiowych. Inwersja w troposferze może wpływać na odbiór w szerokim zakresie częstotliwości, zaczynając od dolnego UKF-u (typowo 50-70 MHz), przez pasma radiowe, telewizyjne, mikrofale, a nawet… widmo optyczne.

Mój zestaw odbiorczy to antena RocketDish 5G31-AC + DBII F52N-PRO na maszcie 18 m n.p.t. z rotorem w okolicach Płocka (114 m n.p.m.).

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Warflying (Wi-Fi scanning) in an airplane up to 450 km

Recently I was traveling by plane over Europe. Of course, I could not resist to check what could be received on 5 GHz there, at an altitude of over ten kilometers…

I took the following equipment for Wi-Fi scanning onboard:

  • Mikrotik Routerboard SXT 5HPnD (AR9280),
  • Raspberry PI 3B with GNSS receiver, RTC and 10 V PoE output – see more: Wardriving @ 5 GHz,
  • USB power bank (5V/2.1A),
  • Nexus 7 tablet.

I was scanning using MikroTik SXT antenna with a built-in radio module. This device is as small as 14×14 cm. The dual-polarization antenna rated at 16 dBi is even smaller, at just 11×11 cm. It was connected to Raspberry PI single board computer.

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June 2019: London, Manchester and Cardiff via tropo in Poland

Ten wpis jest dostępny także w języku polskim: Tropo: Londyn, Manchester i Cardiff w Polsce

The early morning of June, 27th 2019 brought one of the biggest tropospheric propagation from Western Europe we have ever observed from Poland. Looking at the results, it can be stated that it was the strongest tropo on the VHF FM band 87.5-108 MHz from the territories of England, the Netherlands and Belgium for at least 15 years (probably since ever), with many transmitters and areas received for the first time. The received signals reached the stereo and even RDS quality on many frequencies, and the maximum distances exceeded 1500 km.

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