Sony SRF-18 Service Manual page 8

SRF-18
THIS NOTE IS COMMON FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed in each block.)
For Printed Wiring Boards.
Note:
• X : Parts extracted from the component side.
• Y : Parts extracted from the conductor side.
• W : Indicates side identifi ed with part number.
• : Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
SRF-18
SECTION 3
DIAGRAMS
For Schematic Diagrams.
Note:
• All capacitors are in μF unless otherwise noted. (p: pF) 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
specifi ed.
• C : Panel designation.
• A : B+ Line.
• H : Adjustment for repair.
• Power voltage is dc 3 V and fed with regurated dc power
supply from TP (BATT+) and TP (BATT–) on the MAIN
board.
• Voltages are dc with respect to ground under no-signal
(detuned) conditions.
no mark : FM
( ) : AM
* : Impossible to measure
• Voltages are taken with VOM (Input impedance 10 M).
Voltage variations may be noted due to normal production
tolerances.
• Signal path.
F : FM
f : AM
: AUDIO IN
E
• IC Block Diagrams
– MAIN Board –
IC101 CXA1129N-T4
30 29 28 27 26 25 24 23
OVER LOAD LOCAL
AGC
OSC
FM/TV
FM/TV
0
RF AMP
1/2
/2
COUNTER
FM/TV MIX PSN
MIX 1
1
PSN
MIX
2
2
FM/TV
FM/TV
1ST LOCAL
OSC
AGC AFC
AM AF AMP
RF AMP
LPF
1 2 3 4 5 6 7
IC201 CXA1522N
16 15 14 13 12 11 10 9
VOLUME
PRE/POWER 1
REGULATOR
PRE/POWER 2
1 2 3 4 5 6 7 8
8 8
22 21 20 19 18 17
FM/TV
38KHz
VCO
FM/AM
FM/TV R CH
VCO LEVEL
SELECT AMP
CONTROL
FM
DISCRI
SEP
BUFF
FM
CONTROL
AMP
FM
LIMITTER
LPF
AMP 38KHz
MUTE
AM AM IF AMP
ST. DC
BPF (FM TUN IND)
DECORDER AMP COUNTER
19KHz
/2
PD
AM
INPUT
19KHz
DET
BUFF
SYNC 0
DET
AGC
FM/AM
SELECT
DETUNE TUNING
DET IND
M/ST.SW
ST.IND
8 9 10 11 12 13 14
16
L CH
AMP
LOAD
SELECT
1/2
FM/AM
15