Electrical Adjustments; Diagrams; Circuit Boards Location - Sony ST-SE520 Service Manual

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ELECTRICAL ADJUSTMENTS

FM Signal Level Adjustment
FM RF signal
generator
Carrier frequency : 98 MHz
Modulation : 1 kHz, 40 kHz deviation
FM ANTENNA
Output level : 6.3 mV (76dBµ)
75 Ω coaxial
(75 Ω open)
(TB101)
Procedure:
1. Tune the set to 98 MHz.
2. Push the DISPLAY button for digital signal meter indication.
3. Adjust RV201 to the place where level and "70dB M" indica-
tion lights on fluorescent indicator tube.
SECTION 3
Adjustment Location:
[TUNER BOARD] — Component Side —
IC201
set
RV201
FM SIGNAL LEVEL

4-1. CIRCUIT BOARDS LOCATION

AC SW board
THIS NOTE IS COMMON FOR PRINTED WIRING
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed
in each block.)
For schematic diagrams.
Note:
• All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.
• All resistors are in Ω and
specified.
• 2 : nonflammable resistor.
• C : panel designation.
Note: The components identified by mark 0 or dotted line
with mark 0 are critical for safety.
Replace only with part number specified.
• U : B+ Line.
• V : B– Line.
• H : adjustment for repair.
• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
no mark : FM
∗
: Can not be measured.
WAVEFORMS
1
4.8Vp-p
4.332MHz
IC802 qf
5 5
Digitized in Heiloo Netherland
SECTION 4

DIAGRAMS

TRANSFORMER board
DISPLAY board
• Voltages are taken with a VOM (Input impedance 10 MΩ).
Voltage variations may be noted due to normal produc-
tion tolerances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
• Circled numbers refer to waveforms.
• Signal path.
F : FM
1 / W or less unless otherwise
4 For printed wiring boards.
Note:
• X : parts extracted from the component side.
• : parts mounted on the conductor side.
x
• b : Pattern from the side which enables seeing.
• Indication of transistor
B C E
These are omitted
2
4.3Vp-p
4.19MHz
IC701 qs
7/23/2017
TUNER board
ENCODER board