GMDSS: Element 7

1. A 16 or 22 MHz when daylight at each end and 8 MHz when dark at each end.
2. B 12 MHz during daylight at each end and 2 MHz when dark at each end.
3. C 8 MHz during daylight hours and 16 MHz during darkness.
4. D 6 MHz during daylight hours and 8 MHz during darkness.

Tip: press A-D to answer