1. K4SWL Antenna Plus - https://kk4z.com/2022/06/05/k4swl-antenna-plus/
** QRPGuys 40m-10m Mini UnUnTenna - https://kk4z.com/wp-content/uploads/2022/06/mini_ununtenna_021422.pdf
2. ELECRAFT KH1 hand-held, 5-band CW transceiver - https://ftp.elecraft.com/KH1/Manuals%20Downloads/KH1%20Owner's%20Manual,%20rev%20B4.pdf
3. Lynovation Radio Control Products - https://ctr2.lynovation.com/announcing-the-ctr2-micro/
4. A prototype 50:75 RF transformer (Прототип радіочастотного трансформатора 50:75) - https://owenduffy.net/blog/?p=35345
5. HF Signal Enhancer for SDR: A Hands-On Build by Steve Allen (KZ4TN). (Підсилювач ВЧ-сигналу для SDR) - https://swling.com/blog/2025/01/hf-signal-enhancer-for-sdr-a-hands-on-build-by-steve-allen-kz4tn/
73 de UT2AB
