TM 11-5820-890-10-1
COMSEC KEYS (Traffic Encryption Key and Key Encryption Key): These are
variables needed for cipher text (CT) operation. A Traffic Encryption Key (TEK)
may be loaded into channels 1 thru 5. A Key Encryption Key (KEK) is only loaded
into channel 6. A KEK must be loaded into an RT before remote fill of a COMSEC
key is possible. It is possible to scroll TEK. KEK’s cannot be scrolled.
LOCAL FILL OF COMSEC KEYS: A COMSEC key is required for CT operation
and is loaded into the RT using a COMSEC fill device. Refer to page 2-38 for local
COMSEC key loading information.
REMOTE FILL OF COMSEC KEYS: A COMSEC key is required for CT operation.
The NCS may send or ERF a COMSEC key to a member RT provided a COMSEC
key is already present in channel 6 (locally loaded). Refer to page 3-16 for remote
COMSEC key loading information.
COMMUNICATING IN AN FH NET: An FH radio net must be opened by the NCS.
This synchronizes the net radios; then normal radio procedures are used for com-
municating. The procedure used to open a net is called cold start net opening.
OTHER FH OPERATIONS: These include updating FH data by ERF, passive late
net entry, and CUE and ERF late net entry. Late entry is used when you are out
of the net for any reason. CUE is used for contacting a FH radio net when you
are not an active member. CUE is also used if you missed your primary net’s
opening, or when requesting entry into an alternate net. CUE may be used if
you are operating a SC radio and wish to contact a FH net.
MAINTAINING RADIO’S MEMORY: Memory, or COMSEC and FH fills plus SC fre-
quencies, is maintained in two ways. Main power, either battery or vehicular sys-
tem, allows radio to retain all memory so long as main power is applied. A hold
up battery (HUB) serves as back up for memory retention. HUB power cuts in auto-
matically if main power is disrupted for any reason, and the HUB becomes opera-
tional whenever the FCTN switch is set to
CLEARING MEMORY: There are four ways data may be cleared from the radio.
SC frequencies are cleared by pressing FREQ and then CLR. COMSEC fill is cleared
by setting the COMSEC switch to position
and waiting for five seconds. FH
data is cleared by setting the FCTN switch to position
and waiting for five
seconds. Also, all memory is cleared by setting the FCTN switch to
and
waiting five seconds.
NOTE
When your radio has a good HUB installed, setting FCTN to causes
no loss of memory.
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