122
FT-857 Operating Manual
S
ETUP
OF
M
EMORIES
FOR
L
OW
E
ARTH
O
RBIT
(
LEO
)
FM S
ATELLITE
O
PERATION
Although the
FT-857
is not capable of “full duplex” operation (simultaneous transmission
and reception), its flexible memory system is ideal for configuring a set of memories for
LEO satellite work.
The example below is designed around the popular satellite UO-14, but the same principles
apply to operation using AO-27, 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 Dop-
pler Shift which occurs on such satellites,
which display rapid apparent motion rela-
tive to an earth-based observer. But if we
can accommodate a set of several fre-
quency 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 42.
First, press the [
FUNC
] key momentarily, then rotate the
SELECT
knob to select Multi
Function Row “a” [
A
/
B, A=B, SPL
]. Press the [
A
](
A
/
B
) key, if necessary, to select VFOa.
Now press the [
BAND
(
DWN
)] or [
BAND
(
UP
)] key to select the 70 cm band. Check the
setting of Menu Mode
No-004
[
AM&FM DIAL
]
. and set this to “
ENABLE
” to allow smaller
frequency increments to be accommodated.
Set the VFOa operating frequency to 435.0800.00 MHz. Now press the [
A
](
A
/
B
) key in
Multi Function Row “a” to select VFOb, and set VFOb to 145.970.00 MHz. Again press the
[
A
](
A
/
B
) key to return to VFOa. Be sure that both VFOs are set to the FM mode, as well.
Press the [
FUNC
] key momentarily, and rotate the
SELECT
knob one click clockwise to
select Multi Function Row “b” [
MW, SKIP, TAG
].
Press the [
A
](
MW
) key momentarily, then rotate the
SELECT
knob while the memory
channel number is blinking; select memory channel M-001, then press and hold in the
[
A
](
MW
) key until you hear the double beep. We have just stored the first downlink (earth
station receiving) frequency into memory.
A
PPENDIX
ø
Menu No-004(AM&FM DIAL) must be set to “EN-
ABLE” to set these frequencies in the FM mode.
AOS = Acquisition of Signal (Beginning of Pass)
LOS = Loss of Signal (End of Pass)
CH #
1
2
3
4
5
R
X
F
REQ
435.080 MHz
435.075 MHz
435.070 MHz
435.065 MHz
435.060 MHz
T
X
F
REQ
145.9700 MHz
145.9725 MHz
ø
145.9750 MHz
145.9775 MHz
ø
145.9800 MHz
N
OTES
AOS
Mid Pass
LOS
