1. HF QRP End Fed Half Wave - https://vk1nam.wordpress.com/2021/03/07/antenna-project-hf-qrp-end-fed-half-wave/
2. K4SWL Antenna Plus - https://kk4z.com/2022/06/05/k4swl-antenna-plus/
** Frankentenna - https://kk4z.com/2022/06/15/frankentenna/
3. Mini Whip - Active HF Antenna - https://gerritvinkies.wixsite.com/pa3dwc/post/mini-whip-active-hf-antenna
4. VDA 30m (antenna) - https://dx.to/vda30/
** VDA 20-17-15m - https://dx.to/vda20-17-15/
5. RSP Spectrum Analyser - https://www.spectrumanalyser.co.uk/index.html
73 de UT2AB
