3 ms·
They use VLF/ELF to send "message pending" and/or some other very short predefined signals. Russian military transmitter (ZEVS) is still operating on 82Hz frequ
by ruslan 16y ago
They use VLF/ELF to send "message pending" and/or some other very short predefined signals. Russian military transmitter (ZEVS) is still operating on 82Hz frequency and uses Earth as an antenna.
http://en.wikipedia.org/wiki/Extremely_low_frequency http://en.wikipedia.org/wiki/Extremely_low_frequency