The purpose of this project to provide small lightweight personal secure digital communication for a local group in an environment where wireless communication services are not provided by commercial cellular corporations (in the mountains, in disaster region with no electricity, in extremely lightly environments >80000 lux, outer space, moons and other planets). The main advantage of this device is extremely low power capability (can be actively used up to a week of communication or in ‘ready to be used’ up to decades from two AAA explosion-free accumulators from one recharge), good practical range, advanced communication security (strong cryptographical encryption and authentication), radiation immune/aware electronics (can detect by hardware soft-errors due to high-radiation particle events), GSM 100% compatible (voice packets optionally can be routed to and from any remote mobile phone without transcoding or archived for later playback on any personal computer or mobile device), communication is addressable and is possible in one-to-one or one-to-many scenarios. Voice intelligibility is good preserving authenticity with no synthetic voice, noticeable artefacts, distortions or parasitic noise.