Yaesu FT-902DM, Instruction Manual

Page: 48 / 55

V R 7 0 1
Q703
Q 7
o
9
Carrier u n i t ( PB - 1 706
A)
7.
A LC LEVEL ADJU STMENT
Q701
X7o3
X7D2
Xrn1
VR,02
Q7os
Q707
Q705
Q705
S e t the M ETER swi tch to ALC, the
�
ODE switch
to U S B or LS B , the MIC GAIN
con trol coun ter­
clockwise , and the VOX GAIN con trol to MOX.
I f
the meter reading is not fully deflected to the
right, adjustment of the A LC l evel con trol VR 2 0 1
on PB- 1 9'9 4 will be required . Adjust VR2 0 1 for a
reading o f
3 5 0
(full scale) and return the VOX
GAIN control to PTT.
8 .
R F SPEECH PROCESSOR ADJUSTMENT
Tune up the transceiver on U S B at 1 4. 2 MHz. Set
VR2 0 2 and the PROC LEVEL controls to the .
center of their range. Apply a
I
kHz audio signal
to the microphone input and adjust i ts level to
the p oint where p ower outpu t levels off after
reaching its maximum value ; d o not advance the
input level past the saturation poin t . Adjust V R2 0 3
so as to ob tain the same power outpu t when the
RF Processor switch is in the ON and OFF posi­
tions.
9.
IF PAS SBAND TUNING ADJUSTMENT
Tune the receiver to J 4.2 MHz in the USB mode
an d set the
WI DTH
con trol t o the 1 2 o 'clock
p osition. Set the R F GAIN control fully clock­
wise.
Change the MODE switch from USB to LSB . The
receiver background noise at the speaker should
not change in pitch.
I f there is any difference ,
adjust VR2 3 0 1 located adj acent to the MODE
switch below the chassis until the noise is of the
same pitch when switching b etween USB and
LSB.
T207
Q207
V R 203 V R202
V R 2 0 1
N B /PROC unit
(PB- 1 994)
VRs, b
V R 2 3 0 1 Mode swi tch
R ej e c t /W i d t h board
( P B - 1 722)
1 0. APF SELECTIVITY
X F2 0 1
T z o z
T z o 1
Q203
M e m o r y un i t
The selectivity of the APF (Audio Peak Filter)
can be adjusted by varying V R 5 0 1 , located on
PB- l
70SIA.
Clockwise rotation of V R 5 0 1 will yield
sharper selectivity of the filter.
AF
u
n
i
t
(PB- 1 705A)
-
4 6
-