TM 11-5820-890-10-3
FUNCTIONAL DESCRIPTION Continued
3. Hopset. The hopset is the set of frequencies that the RT hops on (changes frequency) during FH. The radio
hops on more than 100 frequencies per second.
4. Lockout set. A lockout set is a series of frequencies that are not used during FH operation. When a lockout
set is loaded into the RT, the frequencies that are contained in the lockout set are no longer part of the
hopping pat- tern. It may not be necessary to load a lockout set (check SOI). However, if one is required, it
MUST be loaded into the RT prior to loading the hopset. Otherwise, the keyboard display will show "L7", "L8",
or both. This means that your RT is missing mandatory lockout sets.
5. FH sync time. This is needed to synchronize FH communications. FH sync time is loaded by transmission
from the net control station radio during ERF. It can also be loaded into the RT by keyboard actions. During
cold start net opening, the member radios receive FH sync time at the same time that the ERF is received.
CUE FREQUENCY: This is a single channel frequency. It is loaded into the CUE channel by keyboard actions. It enables
someone not in a FH radio net to "CUE", or con- tact, the FH net. When CHAN is set to CUE, MODE to SC, and handset
push-to-talk is pressed, "CUE" is displayed at NCS or designated RT display. The CUE frequency is listed in the SOI.
Only the NCS, alternate NCS, and designated members should load the CUE frequency.
LOADING FH DATA: Two methods can be used for loading FH data. One is called "local fill"; the other, "electronic
remote fill (ERF)." Both load the data first into the RT holding memory; the holding memory is a temporary memory, so the
data must be moved to the RT permanent memory. It is stored in the permanent memory. Both make use of the RT
keyboard. When a button is pressed, the display responds. It shows what has been done. It also shows when another
keyboard entry is needed. An underline (_) on display means another entry is needed.
LOCAL FILL OF FH DATA: Local fill makes use of an ECCM fill device. There is little difference between lockout set and
hopset loading. When a hopset is being loaded and Sto/Ent is pressed, the display shows "Sto_". The line on the display
means another keyboard entry is needed. The operator must press a number button (1 - 6) to indicate in which channel
the hopset is to be stored. The line on display then changes to the channel number. The hopset is then in the permanent
memory.
ERF (ELECTRONIC REMOTE FILL): ERF does not make use of a fill device. Instead, the net control station (NCS)
transmits lockout sets and/or hopsets to net member radios. There is little difference between a hopset ERF, and a
lockout set ERF. When the NCS sends a hopset, the following are sent at the same time: Hopset, net ID and FH sync
time.
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