Sharp DV-1600 Series - Page 6

Step
Adjust point
Connection
Procedure
(6) Close tuning control door (lid),
’
then AFT switch will turn on
automatically.
, (7) Adjust T203 to have zero beating
on oscilloscope as shown in Fig. 11.
Adjustment error:
36.875 MHz + 25 kHz
6.
RF AGC cut-in:
1 (1) R
eceive standard colour bar signal.
R209
If reception of colour bar signal
is not possible, receive VIII band
signal instead.
Input intensity:
Within 75 dB to 85 dB
1 (2) Connect oscilloscope to TP203.
Oscilloscope range: 0.2V/div.
Sweeping time: 20psec/div.
Sync operation: Horizontal
/ (3) Turn R209 until there appears
I
noise on oscilloscope as shown
I
in Fig. 10.
/ (4) T urn back R209 slowly until
there disappears noise on oscil-
loscope. At the time, horizontal
sync signal should keep on the
I
same level as before. (Fig. 11)
keep on this level.
1 (5) Set signal intensity at 90 to 95
dB, and see that there is no
black letter and sound beating
on oscilloscope.
1 (6) Set signal intensity at 60 to 65
I
dB, and see that there is no
Figure 11.
noise on oscilloscope.
I
7.
SIF detection coil:
I (1) Voltage setting of PIF AGC:
(1) Adjust T301 so that AM signal (400 Hz)
T301
Apply DC 3V to pin @ of
on oscilloscope becomes minimum.
IC20 1.
(2) Adjust sound volume to
maximum.
(3) Connect signal generator’s output
to pin $!J of IC201.
400Hz
(AM signal)
Figure 13.
!
Figure 12.
Zero
AM signal
l Frequency: 5.5 MHz
l Modulation: 400 Hz, AM 30%
Figure 14.
l Generator’s output level:
74 dB
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