5
5
SECTION 4
DIAGRAMS
4-1. CIRCUIT BOARDS LOCATION
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
1
/
4
W or less unless otherwise
specified.
• 2 : nonflammable resistor.
• C : panel designation.
For printed wiring boards.
Note:
• X : parts extracted from the component side.
• x : parts mounted on the conductor side.
• b : Pattern from the side which enables seeing.
• 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
IC802 qf
Note: The components identified by mark 0 or dotted line
with mark 0 are critical for safety.
Replace only with part number specified.
• Indication of transistor
• 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
SECTION 3
ELECTRICAL ADJUSTMENTS
FM Signal Level Adjustment
Adjustment Location:
[TUNER BOARD] — Component Side —
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.
2
IC701 qs
FM RF signal
generator
set
FM ANTENNA
75 Ω coaxial
(TB101)
Carrier frequency : 98 MHz
Modulation : 1 kHz, 40 kHz deviation
Output level : 6.3 mV (76dBµ)
(75 Ω open)
IC201
RV201
FM SIGNAL LEVEL
AC SW board
ENCODER board
TRANSFORMER board
DISPLAY board
TUNER board
C
These are omitted
EB
4.8Vp-p
4.332MHz
www.freeservicemanuals.info
Digitized in Heiloo Netherland
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