Operation Manual

77FT-817ND Operating Manual
SETUP OF MEMORIES FOR LOW EARTH ORBIT
(
LEO
)
FM SATELLITE OPERATION
Although the FT-817ND is not capable of “full duplex” operation (simultaneous transmis-
sion and reception), its flexible memory system is ideal for configuring a set of memories
for LEO satellite work.
The example at the right is designed around
the popular satellite UO-14, but the same
principles apply to operation using AO-27,
SO-35, and other such satellites.
First, set up a table of the required operat-
ing frequencies. For UO-14, a typical setup
table is shown at the right:
The above frequencies are nominal, and the changing frequencies reflects the Doppler Shift
which occurs on such satellites, which display rapid apparent motion relative to an earth-
based observer. But if we can accommodate a set of several frequency pairs in our memory
system, frequencies that reflect the frequency relationships encountered during a typical
pass, we will have a good chance of having our frequencies properly aligned when it is time
for making a QSO.
So we need to store the above frequency matrix into memories. Note that the receiving
frequency and transmitting frequency are on different bands. Therefore, we will use the
“Split Frequency Memory” storage technique described on page 43.
First, press the key momentarily, then rotate the knob to select Operating Func-
tion Row 1
[
A/B, A=B, SPL
]
. Press the
(
A/B
)
key, if necessary, to select VFOa.
Now press the or key to select the 70 cm band. Check the setting
of Menu #04 (AM&FM DL). and set this to “ENABLE” to allow smaller frequency incre-
ments to be accommodated.
Set the VFOa operating frequency to 435.080.00 MHz. Now press the
(
A/B
)
key in
Operating Function Row 1 to select VFOb, and set VFOb to 145.970.00 MHz. Again press
the
(
A/B
)
key to return to VFOa. Be sure that both VFOs are set to the FM mode, as
well.
Press the key momentarily, and rotate the knob one click clockwise to select
Operating Function Row 2
[
MW, MC, TAG
]
.
Press the
(
MW
)
key momentarily, then rotate the knob while the memory chan-
nel number is blinking; select memory channel M-001, then press and hold in the
(
MW
)
key until you hear the double beep. We have just stored the first downlink (earth station
receiving) frequency into memory.
APPENDIX
AOS = Acquisition of Signal (Beginning of Pass)
LOS = Loss of Signal (End of Pass)
CH #
1
2
3
4
5
RX FREQ
435.080 MHz
435.075 MHz
435.070 MHz
435.065 MHz
435.060 MHz
TX FREQ
145.9700 MHz
145.9725 MHz
145.9750 MHz
145.9775 MHz
145.9800 MHz
NOTES
AOS
Mid Pass
LOS