Morse telegraphy

Field telephone

Shortwave radio communication

"Dom" satellite antenna

Handy statt Smartphone

Robust technology

Othernet

Hand crank generators

Hybrid-Smartphones

Network radios

Freenet radios

GMRS - General Mobile Radio Service

Starlink

Knife and tool

Wood to electricity

Outdoor Smartphones

Internet via balloons

Portable solar cells

Satellite radio

Special radio for hikers and mountaineers