channel and its LSET code to be displayed. Valid LSET
channels are I through 6. Other possible messages are
ERROR and NO LSET (no LSET loaded for that chan-
e L5. In FH mode, this function is used to
time FH operations. If the scratchpad is blank,
depressing L5 will change the display of time stored in
the transceiver. If time is not available from the
transceiver, the display remains blank. If valid data is
scratchpadded, the data will be displayed adjacent to L5
and sent to the transceiver. Valid time data is day (0
through 99), hours (0 through 23), and minutes (0
through 59). Data fields not entered are considered
f R1. Depressing RI will cause the legend
at RI to be boxed and the transceiver to be put into the
LATE NET E (entry) mode. The late net mode can be
used to re-synchronize the radio if communication has
been lost due to drifting of the clock.
g R3. The function key R3 of the 2-FM
SETUP page (FH format) is the CLEAR function key.
Pressing R3 with a valid hopset (1-6) or lockset (L1-L8)
channel number in the scratch pad will cause the
associated hopset or lockset to be cleared from the
h R5. R5 is used to store hopsets and
locksets from a fill device into the transceiver. When
depressed, the legend at R5 will be boxed and will load
the HSET or LSET channel entered into the scratchpad
with the data from the fill device. Valid HSET entries are
1 through 6 or Hi through H6. Valid LSET entries are L1
through L6 or the single character L. ERROR or BAD
can be displayed for unsuccessful or bad fill attempts.
In the air. The legend at R4 and R5 will
be blanked in 66 air because the TSEC FILL and FILL
function is only available when the aircraft is on the
FH/M (frequency hopping - master
mode). This mode is the master/controller versus the
member mode of the frequency hopping mode of the
VHF-FM transceiver. The data at the top center of the
Top line - 2-FM SETUP
Second line - The currently selected
channel; and the text NET and the net number
Third line - CONTROL or CONTROL/NO TSEC,
but can read FAIL, EMER, or TUNING if appropriate.
The display formats vary somewhat depending upon
whether the aircraft is on the ground or in the air.
1 On the ground.
a L1. Successive depressions of
L1 will cause the mode to change from SC to FH to
FHIM, with the active mode boxed.
The differences between the FH/M and FH
mode display formats are:
FH/M mode - L2 allows the operator to send
(versus receive) frequency hopping data
R1 (LATE NET) - Blanked.
If a TRANSEC variable has not been
loaded, the text NO TSEC will appear
on the third line of text at the top
center of the display.
b L2. The ERF SEND key is used to
initiate transmission of frequency hopping data from the
NET controller's radio. When data is in the scratchpad
and L2 is depressed, the text SENDING HSET CH X or
SENDING LSET CH X (where X is the HSET or LSET
channel in the scratchpad) is displayed. Valid
scratchpad data is I through 6, HI through H6, or L1
through L8. The sending legend is displayed for 12
seconds or until the radio has finished sending.
2 In the air. The on-ground and in-air
display formats for the FH/M mode are the same except
that the legends TSEC FILL (R4) and FILL (R5) keys are
blanked (these functions are not available in flight).
c. FM FREQ List Page. The FM frequency list page is
accessed by depressing R4 on the COMM control page
when FM FREQ is displayed at R4. This page is used to
enter/delete preset frequencies and hopsets/locksets for
the VHF-FM transceiver. On power-up, all data
displayed in the frequency list box (right side of the
display) at shutdown is recalled, and the hopset/lockset
information stored in the radio is recalled and displayed
in the hopset/ lockset box (left side of the display).
Leading zeroes and zeroes in the hundredths and
thousandths position are not displayed.
ADD NET function key. Function
key L1 of the UHF frequency list page is the add net
function key. The ADD NET key is used to add data to
the AJ NET list. Entering valid data in the scratchpad
and pressing LI causes the data in the scratchpad to be
entered into the AJ NET list. Valid data consists of a
valid net channel (1-20) followed by a valid net number (I
to 5 digits with an optional decimal point whose final