Associations

• Österreichischer Versuchssenderverband (OEVSV) https://www.oevsv.at/
• American Radio Relay League (ARRL) https://www.arrl.org/
• Deutsche Amateur-Radio-Club (DARC) https://www.darc.de/

Radio Construction

• DX Explorer https://dxexplorer.com/
• w2aew https://www.youtube.com/@w2aew
• devttys0 https://www.youtube.com/@Analogzoo
• IMSAI Guy https://www.youtube.com/@IMSAIGuy
• M0NTV Homebrewing https://www.youtube.com/@M0NTVHomebrewing
• LC Filter Design Tools https://markimicrowave.com/technical-resources/tools/lc-filter-design-tool/
• Toroids Calulations https://www.toroids.info/
• TRX Lab https://www.youtube.com/@TRXLab

HAM Shops

• Funktechnik Bielefeld https://www.funktechnik-bielefeld.de/
• Funkelektronik.at https://www.funkelektronik.at/
• Ele Shop https://eleshop.de/
• DX Wire https://www.dx-wire.de/
• Spiderbeam https://spiderbeam.com/
• QRP Labs http://qrp-labs.com/
• WIMO https://www.wimo.com/

Morse

• Learn CW Online (LCWO) https://lcwo.net/

Indicies, Data, Logs

• HF Propagation map https://hf.dxview.org/
• VHF Propagation map https://vhf.dxview.org/
• DR2W Propagation map https://dr2w.de/dx-propagation/
• QSL net Propagation map https://www.qsl.net/4x4xm/Propagation/Live-HF-Propagation-Map.htm
• Propagation Map: HamDXMap