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Panasonic Technics ST-CH7L Service Manual page 7

Lw/mw/fm stereo tuner
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SCH EMATIC
DIAG RAM
(Parts list on pages 17~20.)
Notes:
eS901,902
: Preset channel switch.
(S901: Up, S902: Down)
eS903
: Band select switch.
eS904
: Memory switch.
eS905, 906
: Tuning switch.
(S905: Up, S906: Down)
eS907,908
: Timer select Switch.
(S907:
Up, S908:
Down)
eS909
: Timer set switch.
@S910
: Clock set switch.
eS9i1
: Timer setting confirmatin switch.
e$912
: Timer cancel switch.
eS913
: Power switch.
indicated voltage values are the standard values for the unit 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.
(_ ): MW voltage, [ ]: LW voltage,
]: MUTING voltage
eimportant safety notice
Components identified by A. mark have special characteristics important
for safety. When replacing any of these components, use only
manufacturer's specified parts.
eThis schematic diagram may be modified at any time with the
development of new technology.
ooo00f
FMOSC
muaep
AMOSC
«Caution!
a>
IC and LSI are sensitive to static electricity.
Secondary trouble can be prevented by taking care during repair.
AM signal
AF signal lines
*Cover the parts boxes made of plastics with aluminum coil.
*Ground the soldering iron.
*Put a conductive mat on the work table.
«Do not touch the legs of IC or LSI with the fingers directly.
Positive voltage lines --=—=—
Negative voltage lines
c—>
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$11
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