Communications involves making radios and telephones work, and knowing how to contact friendly forces (or eavesdrop on enemy forces).
This is above and beyond simple things like turning on the radio, finding a frequency and keying a microphone - which just about any officer and NCO can do easily.
Sample skills include:
Rig a simple telephone system. With equipment and materials: Easy. With extemporized equipment and material: Difficult.
Figure out how to use a foreign or unfamiliar radio set: Difficult.
Overcome atmospheric interference: Average. One level more difficult in Mountains.
Improve Range of Radio Set: Difficult. This involves using antenna placement and frequency selection to increase the range of a radio by 20% (or, at referee's discretion, more if the character rolls "Formidable"). This takes time and can not be done on the move.
Successfully counter jamming: Formidable.
Repair damaged equipment. Telephone: Average. Radio: Difficult.
Extemporize simple radio equipment. Receiver: Difficult. Transmitter (Morse): Formidable. Voice: Impossible.
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