Technics ST-G470 Service Manual

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R305 82K
R335 3.9K] | &
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TUNING
SWITCH
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REGULATOR
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| SCH EMATIC DIAG RAM (Parts list on page 19~21)
(This schematic diagram may be modified at any time with the development
of new technology.)
Notes:
S701: Power switch in “‘on’’ position.
e$901~S910: Preset tuning (39 channel random preset tuning) switches. Judd obcaranibilerean pais
sed ou penis oe pa path The ceramic filters (CF101, CF 102) for FM-IF circuit are available in three
$907: CH7, $908: CH8, $909: CH9, ranks. For this circuit, be sure to use the ceramics of the same rank in a pair.
$910: CHO At repairing and replacement, pay close attention to the diodes (D907, D908)
e$911, $912 Band selectors (band selector) switches. for use as different diodes must be used depending on each rank of the
$911: FM, S912: AM ceramic filters.
S914: FM mode selector (FM-mode) switch.
eS915: FM signal-strength indication (FM-signal) switch.
S916, S917: Preset channel (preset channel) switches. Color marking
$916: DOWN, S917: UP (Red, Blue or Orange)
eS918: Memory (memory) switch.
$921, $922: Tuning (tuning) switches.
$921: UP, S922: DOWN SFE
measured by the DC electronic circuit tester (high-impedance) with
the chassis taken as standard. Therefore, there may exist some
errors in the voltage values, depending on the internal impedance
of the DC circuit tester.
Note: © mark: Diode is used.
x mark: Diode is not used.
o( aa ): AM voltage +Caution!
| muting voltage IC and LSI are sensitive to static electricity.
° Positive voltage lines (+) Secondary trouble can be prevented by taking care during repair.
Negative voltage lines (—) _“""* AF signal +Cover the parts boxes made of plastics with aluminum coil.
cae FM OSC FM signal «Ground the soldering iron.
saab AM OSC => AM signal +Put a conductive mat on the work table.
e|mportant safety notice *Do not touch the legs of IC or LSI with the fingers directly.
Components identified by A, mark have special characteristics
important for safety. When replacing any of these components, use
only manufacturer’s specified parts.
m@ TERMINAL GUIDE OF IC’S, TRANSISTORS AND DIODES
AN6554F
M7001
M50941-421SP
AN7274NS
| AN74728 |
MA4062, MA4082M
MA4140M, MA4051M
MA4300M
2SA1309, 2SC3311
2SD1450,
DTC144ES,
2SA1253RSTAC
>
cg
28C1310, 2SC3940 MA165, MA150FV
1SR35200
Anode
Anode
Cathode
Cao—tq-—0 A
Cathode
Cac—fe-—o A
—12—
ap vials —a FREQUENCY
e\|ndicated voltage values are the standard values for the unit a ae 10.67 MHz

Technics ST-G470 Specifications

General

Brand	Technics
Model	ST-G470
Category	Tuner
Language	English