Yaesu FT-901DM Maintenance Service Manual page 26

Split-frequency control may be obtained with the
memory system or the FV-901 synthesized scan-
ning VFO. The switches involved in frequency
control are as follows:
MR
TX MR
RX MR
VFO
EXT
Note:
This button recalls the memorized fre-
quency for control of the transceive
frequency.
This button recalls the memorized fre-
quency for control of the transmit fre-
quency.
This button recalls the memorized fre-
quency for control of the receive fre-
quency.
Frequency control is by means of the
internal VFO as controlled by the main
tuning knoh.
This switch selects the FV-901 synthe-
sized scanning VFO for frequency con-
trol as follows: with the EXT and MR
buttons pushed, transceive frequency
control is by means of the external VFO.
With the EXT and TX MR _ buttons
pushed, the external VFO controls
the transmit frequency while the internal
VFO controls the receive frequency.
With the EXT and RX MR buttons
pushed, the external VFO controls the
frequency while the internal
VFO controls the transmit frequency.
receive
This button is used to store a frequency
in memory. THE FREQUENCY DIS-
PLAYED ON THE DIGITAL READ-
OUT WILL BE THE FREQUENCY
STORED WHEN THE M BUTTON
IS PRESSED. When the M button is
pressed. the frequency previously stored
in memory will be destroyed. When the
power is turned off, the frequency is
lost from memory.
GENERAI
Operation of the memory system is perhaps best
described by the use of some examples:
(2)
1-21
(1) You are operating on a net on 3970 kHz and
must QSY down 10 kHz to handle a piece of
traffic. With the VFO button depressed and
the main dial on 3970 kHz, press M; 3970 is
now memorized. Move the main dial down
to 3960 kHz to handle the message. When
finished, press MR for instant return to 3970
kHz. The main dial may be left at 3960 kHz
if further QSY to that frequency is antici-
pated. To return to 3960 kHz, simply press
VFO.
You are operating split frequency on 40
meter phone, and you hear DXIDX on 7090
kHz, listening for calls on 7205 kHz. With
the VFO button depressed and the main
dial on 7090 kHz, press M to store 7090 kHz
in memory, and press RX MR to lock the
receiver on 7090 kHz. Turn the main tuning
dial to 7205 kHz: you will now be transmit-
ting on 7205 kHz and listening on 7090 kHz.
To listen to the pile-up on 7205 kHz of
stations calling DX1DX, push VFO; you will
now be listening and transmitting on 7205
kHz, and another press of RX MR will return
you
to 7090 kHz for receive. If DXIDX
should begin to drift slightly in frequency,
push TX MR and M to store 7205 kHz in
memory and lock the transmitter on that
frequency. Place the main dial on 7090 kHz
for precise tracking of the unstable DXIDX
signal.
(3)
You find DXIDX on 21270 kHz, working
stations by order of call area. By pressing the
M button, 21270 kHz may be stored in
memory and the operator may periodically
check to see if his call area is being acknowl-
edged by pressing MR or RX MR.
Note:
After the M button is pushed, the VCO
requires 10 seconds to stabilize on the
memorized frequency. If one of the MR
buttons is pushed during this 10-second
period, some "drifting" of the memorized
frequency may be observed.