Vertex Standard FT-857 manual Appendix, Above frequencies are nominal

APPENDIX

SETUP OF MEMORIES FOR LOW EARTH ORBIT (LEO) FM SATELLITE OPERATION

Although the FT-857is 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-	CH #	RX FREQ	TX FREQ	NOTES
ing frequencies. For UO-14, a typical setup
	1	435.080 MHz	145.9700 MHz	AOS
table is shown at the right:
	2	435.075 MHz	145.9725 MHzø
The above frequencies are nominal, and	3	435.070 MHz	145.9750 MHz	Mid Pass
	4	435.065 MHz	145.9775 MHzø
the changing frequencies reflects the Dop-	5	435.060 MHz	145.9800 MHz	LOS

pler Shift which occurs on such satellites,	ø Menu No-004(AM&FM DIAL) must be set to “EN-
which display rapid apparent motion rela-	ABLE” to set these frequencies in the FM mode.
tive to an earth-based observer. But if we	AOS = Acquisition of Signal (Beginning of Pass)
can accommodate a set of several fre-	LOS = Loss of Signal (End of Pass)

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.

122 FT-857 Operating Manual