A couple of weeks ago I started to gather my first experiences with software defined radios (SDR) and active antennas. I started with low investment, using the RTL SDR dongle, but I quickly realized that using the direct sampling mode for HF is not an ideal solution and added the Spyverter HF up-converter.
For my first trials I used a Mini Whip from RA0SMS as antenna, but the results were quite disappointing.
![mini-whip](https://klsin.bpmsg.com/wordpress/wp-content/uploads/2021/02/IMG_20201017_071329-1024x1024.jpg)
Finally, I ended up with an active loop antenna (see featured image), using the Cross-country Wireless Loop antenna pre-amplifier (10 kHz to 30 MHz version). The pre-amplifier is powered with 13.8 V via a bias-tee. Common mode chokes on the antenna line and all power lines helped to reduce noise, especially on the low bands. This is final hardware setup setup:
![](https://klsin.bpmsg.com/wordpress/wp-content/uploads/2021/02/IMG_20210219_134754-1024x764.jpg)
The setup is now running 24/7 on a Raspberry Pi 3B+ using GQRX and WSJT-X. I was surprised, how many stations and countries can be decoded down to 80 and 160 m.
![](https://klsin.bpmsg.com/wordpress/wp-content/uploads/2021/02/Screenshot-2020-12-19-at-21.56.49-1024x640.png)
![PSK-80m](https://klsin.bpmsg.com/wordpress/wp-content/uploads/2021/02/Screenshot-2021-02-12-at-07.21.40-1024x640.png)
Further Information
Talk given during SARTS monthly meeting
PSK reporter link to stations currently received by 9V1KG