1. Tektronix 491 step attenuator - http://qrp.gr/atten/
** Simple and effective HF preselector - http://qrp.gr/hfpreselector/
2. How to add a band to antenna (Як додати діапазон до антени) - http://dl2kq.de/ant/3-140.htm
3. The Communicator March - April 2025 - https://ve7sar.blogspot.com/2025/02/the-communicator-march-april-2025.html
4. OL-SDR - https://www.olliter.com/download-en.html
5. Magnetic Return SOTA Paddles CW - https://www.thingiverse.com/thing:6827582
73 de UT2AB
