Sony NTM-30, Service Manual

Page: 12 / 17

NTM-30
– 15 – – 16 –
4-5. SCHEMATIC DIAGRAM – RX Board –
Note on Schematic Diagram:
• 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.
•
¢
: internal component.
• C : panel designation.
•
U
: B+ Line.
•
H
: adjustment for repair.
• Power voltage is dc 9 V and fed with regulated dc power
supply from battery terminal.
• Voltages and waveforms are dc with respect to ground
under no-signal conditions.
no mark : RX
• Voltages are taken with a VOM (Input impedance 10 M
Ω
).
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.
N
: RX
• IC Block Diagrams
IC201 TA31136FN
LOCAL
OSCILLATION
RSSI
QUADRATURE
DETECTION
1 2 3 4 5 6 7 8
9 10 16 15 14 13 12 11
NOISE
AMP
FILTER
AMP
IF AMP
BUFFER
MIXER
DETECTOR
NOISE
COMPARATOR
MIX IN GND N-REC N-DET RSSI IF OUT QUAD AF OUT
OSC IN
OSC OUT MIX OUT
VCC
IF IN
DEC
FIL OUT
FIL IN
L.P.F
IC202 CXA1522M
PRE/POWER 2
PRE/POWER 1
VOLUME
REGULATOR
IN1 REG VOL NF1 GND1 P-GND1 OUT1 VCC
IN2
NC NC
NF2
GND2
P-GND2
OUT2
RIPPLE
16 15 14 13 12 11 10 9
1 2 3 4 5 6 7 8
• Waveforms
1
IC201
2
(OSC OUT) (CH A) (RX mode)
500 mV/DIV, 50 nS/DIV
2
IC201
2
(OSC OUT) (CH B) (RX mode)
500 mV/DIV, 50 nS/DIV
3
IC201
2
(OSC OUT) (CH C) (RX mode)
500 mV/DIV, 50 nS/DIV
640 mVp-p
60.76 nS
500 mVp-p
60.723 nS
500 mVp-p
60.686 nS