Yaesu FT-712RH, Technical Supplement

Page: 28 / 33

C. Receiver
Set up the test e q u i p m e n t as shown in
Figure 2. All adjustment points are on the
Main Unit.
d) Confirm 12dB SINAD sensitivity of
-7.5dBu (0.2 l u V ) or better on the
SINADDER.
Figure 2
RECEIVER ALIGNMENT SETUP
1) Interstage Transformers
a) Modulate the RF signal generator
for ±3.5 kHz deviation of a 1 kHz
tone.
b) Tune the transceiver and signal
generator to the same frequency
at the center of the band, and set
the i n j e c t i o n level to produce
midrange S-meter indication.
c) Adjust TC1001, L1004, T1001 and
C V I 001, in that order, for maximum
S-meter i n d i c a t i o n . Reduce the
injection level, if necessary, to
keep the S-meter near midrange.
2) S-Meter Calibration
a) At the center of the band, set the
signal generator for 30dBu (50uV)
injection with ±3.5 kHz deviation
of a 1 kHz tone.
b) Adjust VR1002 so that all S-meter
segments are just on.
3) Scanner Center-Stop
a) C o n n e c t the DC voltmeter ( 3 V
r a n g e ) b e t w e e n TP401 ( + ) and
TP402 (-) on the IF Unit.
b) Tune the transceiver to 435.000 or
445.000 M H z , and set the SQL
f u l l y counterclockwise (the BUSY
lamp should be lit).
c) Tune the signal generator to the
same frequency, and inject 20dBu
(5uV) with ±3.5 kHz deviation of a
1 kHz tone.
d) A d j u s t V R 1 0 0 1 for 0V on the
voltmeter.
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