URR-R389. Figure 2-3 illustrates a typical vlf
receiving system, using the AN/BRR-3 receiver. Most
surface ships no longer receive vlf broadcasts.
However, you will probably find one of these receivers
mounted somewhere in your message center or radio
room.
LOW-FREQUENCY COMMUNICATIONS
The low-frequency (lf) band occupies a very small
portion of the radio frequency spectrum. However, the
Navy’s requirement to provide the best possible
communications to the fleet requires operation on all
frequency bands. The low-frequency band is used for
long-range direction finding, encrypted medium- and
long-range communications, and aeronautical radio
navigation.
Lf Transmit
The low-frequency transmitter is a part of the Fleet
Multichannel Broadcast System, operating at high
Figure 2-3.—Typical vlf receiving system.
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