Sony HCD-D790 Service Manual page 22

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FM Polar Adjustment (East European, CIS model only)
Connection 1:
FM RF SSG
Carrier frequency: 69 MHz
1 mV (60 dB µ ) (at 75 Ω open)
Output level :
Modulation: AUDIO 1 kHz, 10 kHz deviation
Connection 2:
AF OSC
FM RF SSG
Audio 31.25 kHz
external
modulation
terminal
Carrier frequency: 69 MHz
1 mV (60 dB µ ) (at 75 Ω open)
Output level :
Modulation: AUDIO 31.25 kHz, 10 kHz deviation
(EXTERNAL MODULATION)
TE
L 13942296513
Adjustment Location: TCB board
[TCB BOARD] (Conductor Side)
Frequency counter
TP1701
(FILTER)
Level meter
TP1702
(VCO)
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75 Ω coaxial
set
FM antenna
terminal (75 Ω )
75 Ω coaxial
set
FM antenna
terminal (75 Ω )
IC17
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Procedure:
1. Set the modulation of FM RF SSG to AUDIO 1 kHz, 10 kHz
deviation according to "Connection 1".
2. Tune the set to 69 MHz.
3. Adjust the RV1702 so that the reading of frequency counter
connected to TP1702 (VCO) becomes within 31.25 kHz ± 0.05
kHz. (VCO adjustment)
4. Then record the reading of the level meter connected to TP1701.
5. Set the modulation of FM RF SSG to AUDIO 31.25 kHz, 10
kHz deviation according to "Connection 2".
6. Tune the set to 69 MHz.
7. Set the CT1701 to be mechanical center.
8. Adjust the L1701 so that the reading of the level meter connected
to TP1701 (FILTER) becomes maximum. (SUB CARRIER
PEAK Adjustment)
9. Adjust the RV1701 so that the level at the moment becomes 14
dB higher value than the level recorded in step 4. (SUB CAR-
RIER LEVEL Adjustment)
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[TCB BOARD] (Component Side)
IC1701
RV1702
VCO
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2 9 9 4 2 8
1 5 0 5 8 2 9 9 4
L1701
CT1701 Sub Carrier Peak
RV1701
Sub Carrier
Level
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2 8 9 9