Fixing Airspy HF+ Discovery VHF interferences issue

A few years ago I bought the original dual port Airspy HF+ and was amazed by it’s reception quality. I’m using this sdr receiver up to this day for both HF and FM DX-ing and couldn’t find any other affordable yet so good receiver. Back in 2021 I bought Airspy HF+ Discovery as a replacement in case my dual port receiver is struck by ESD during lightning storm or something else.

Airspy HF+ Discovery

Most noticeable differences are lack of metal casing which if present, could be useful in noise and interference reduction, and it has only a single SMA port which is fine for simple setup with single wideband scanner antena, but it’s definitely problematic for someone using separate HF and VHF antennas for better gain and performance. Similarly to dual port model, this device also uses micro-USB port which can potentially cause some troubles. If you stumble upon a connection problem when your computer doesn’t detect a device, or does detect but for some reason SDR software can’t connect to it, please check your usb cable. In my experience even good looking cables with no visible damage to the plug can be faulty, that’s why I’m using my trusted high quality cable filled with ferrite chokes/beads.

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Dell Wyse 5070 – Home Server

Recently I have upgraded my home server to Dell Wyse 5070 Extended. This is a very interesting low power computer in a small form factor. My unit came with Pentium J5005 CPU, 8 GB DDR4 RAM (2 × 4 GB), an Radeon E9173 PCIe graphics card and a M.2 SATA SSD drive. The case is really nice, but the Windows sticker is not. There are many ports around, but I’m not going to use most of them anyway.

My previous setup based on Celeron J1900, 16 GB RAM and Intel 730 SSD has been working fine for 7 years with many services, including website. I decided to build a new Linux home server, which could also be sufficient for such a long time, while still keeping the power consumption at a low level.

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Nowa era telewizji cyfrowej w Polsce

W momencie pisania artykułu jesteśmy dosłownie na półmetku wdrożenia nowego standardu nadawania naziemnej telewizji cyfrowej DVB-T2 HEVC. Parę tygodni temu zakończył się drugi etap, którego sam mogłem doświadczyć, a już wielkimi krokami nadchodzi kolejny trzeci. Co oznacza ta cała zmiana standardu? Jak się przygotować do zmian lub jak przywrócić możliwość oglądania telewizji, gdy okazało się, że niestety nie byliśmy przygotowani do zmiany standardu. Wszystko postaram się Wam opisać w tym artykule o nietypowej jak na stronę tematyce.

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Bandscan w Barcelonie – 2022-05-02

W związku z wyjazdem służbowym postanowiłem zabrać ze sobą radio Xhdata D808. Radio to cechuje się nadzwyczaj dobrą selektywnością na UKF, możliwością przestrajania o 10kHz oraz posiadanym RDS, w dodatku jest kompaktowe oraz lekkie, także świetnie nadaje się do podróży. Przy okazji zabrałem również ze sobą zwijaną antenę Sony AN-71 zapinaną na antenę teleskopową, która ze względu na potworny QRM na niższych pasmach KF raczej się nie przydała.

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Raspberry PI 4: PoE with LM2596

During last Black Friday I bought Raspberry PI 4 on Aliexpress for just $36. After initial tests I’ve found out that a good cooling case is definitely a must have. The SoC quickly reaches 80°C under a full load and then throttles from 1.5 to 1.0 GHz per ARM core to maintain the temperature limit, so I ordered a very nice Chinese aluminum case. I love PoE devices – my new toy must also support Power over Ethernet – and it does!

I took a cheap LM2596 DC converter and installed it together with the board in the aluminium case.

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