English / News / Aktualności / Tropo / Wi-Fi DX

5 GHz Wi-Fi DX record – Denmark logged in Poland @ 745 km

by kkonrad1

A remarkable tropospheric ducting occurred on August 11 and 12, 2020 between Poland, Sweden and Denmark. The propagation forecasts, which use color hue to scale their intensity, featured red shades over the Baltic Sea. Such a propagation strength is very rare, if ever seen on a forecast for this area. I was looking forward for something extraordinary, especially on the microwave bands. My stationary Wi-Fi DXing setup has been damaged three months ago. I could not miss such an opening, so a DX-pedition was the only option. In the evening of August 11 I made an opportunistic decision to visit the Dylewska Góra in north-eastern Poland. A few hours later, I was standing there with an antenna inside a lookout tower. 

With its tip at 312 m ASL, Dylewska Góra (Dylewska Mountain) near Ostróda is the highest hill of the whole north-eastern Poland. There is a wooden lookout tower atop which provides fantastic unobstructed views between 175° to 340° azimuth with optical visibility up to around 50 km. The driving distance from my location is 135 km and I arrived there in two hours, in the middle of the night (2 AM). I knew that place as I have visited it already once with my friend. Back then in the 2018 we encountered a typical morning inversion without any notable long-range ducting (see the report: Early morning on Dylewska Góra).

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English / News / Aktualności / Tropo / Wi-Fi DX

New Year 2020: Excellent inversion over Poland

by kkonrad1

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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News / Aktualności / Tropo / Wi-Fi DX

Nowy Rok 2020: Rekordowa inwersja nad Polską

by kkonrad2

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.

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English / Hardware

Laptop upgrade: Dell Latitude E7440 → E7270

by kkonrad7

I have been using my Dell Latitude E7440 laptop (i7-4600U / 16 GB RAM / 480 GB SSD) literally every single day for almost 6 years. I still say this is one of the best laptops ever built. I’ve been looking for a upgrade for quite a long time though. However, I could not wait any longer, because my current laptop would require some expensive investments, including new:

  • High-capacity battery – that would be the third one (original $100).
  • Keyboard – that would be also the third one (original $50).
  • LTE Cat 6 miniPCIe module – to replace the Cat 4 modem ($100).
  • Some case elements – e.g. bottom cover with rubber feet, but also palmrest w/ touchpad in the near future…

In fact, no wonder that I could not find anything suitable for a very long time, because my requirements for a new laptop were very detailed and specific. 

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English / Hardware

MikroTik RouterBOARD hardware disappointment

by kkonrad0

I’ve been lately looking for a small 10/100M Ethernet switch with a USB and both PoE input and output port (Power over Ethernet). The MikroTik RouterBOARD hAP (RB951Ui-2nD) looked pretty good, so I ordered one. The 2.4 GHz Wi-Fi interface was unnecessary, but the price was acceptable anyway, as I found a used device in excellent condition at just $25 including shipping.

As usually, the first thing I did after receiving the package was the teardown. The PoE ports are usually dedicated for some remote devices connected with long Ethernet cables and located outdoors. Therefore, a special protection should be included in the front of the controller (QCA9531 SoC in hAP). Unfortunately, this is not the case of RB951Ui-2nD. Although the engineers designed the PCB of this device with TVS diodes on both PoE input and output ports, the final product does not contain them. Protection for other ports was not planned at all.

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