Technics SE-A900S User Manual

SU-C800U
Function of IC Terminals
© 1C701 (M37470M2332S)
Terminal
ho. | "Namen [VO
1 SDATA
Terminal
vA >
fl
@
/O
Data signal output for input select IC (IC201 and
2) no =) no
as
—
N VCC
RESET
i and
CLOC coe signal output for input select IC (IC201
Aa
Lo. °)
OQ
OLIO
N Nn
(an) [om]
Nol
torobe signal output for input select IC (IC201 and
STB 19 BACKUP
H
SELLED2 20 EMCON
SELLED1 Input select LED drive signal output 21 BATLVL2
N ine)
8
Y
N Motor drive signal output (Volume down) 23 MUTLED
24 SRCELED
VRUP Motor drive signal output (Volume up)
ASWMUTE Audio signal muting signal output 25 TP2MLED
0 BATLVL1 Not used, connect to GND 26 TP1MLED
“J
< |M roe ie 6 |r
=io
(on)
EYAD Power switch and Tape monitor switch signal 27 ATFLED
SWA Input selector switch (S804) signal input 28 BATELED
Not used, connect to GND
ox
O
VREF Reference voltage input 29 BATRLY
30 2) HRGRLY
Connect to the ceramic oscillator
XOUT 31 OPTRLY
Relay drive signal output
Power control signal output
32 PWRRLY
G) =
O
Connect to GND
— | —e | me fF ot fl J Do; oa; | © fw |] —
x rd
m@ Schematic Diagram
Page
MAIN CIRCUIT oii ccccccccccccsssscssssscssssscsessesvsssssesestensestenseseesstenessetaee 6~9
BEY TONE SWITCH CIRCUIT oo cccccsssssssstsssssntstntneieneetnene 7,8
VOLUME CIRCUIT oooccccccccccccsssssssssssssssssssssestessssitassusstusssiaeseee 7
Pe] BALANCE VR CIRCUIT ooioiicccccssssssssssssststssiststrstetntnesetneee 7
[5] POWER SWITCH CIRCUIT ooo ccccssesseeseee se heeeeweettie: 7
OPERATION CIRCUIT ooo cccccccccccscssssssssssssssssssssnsestssesnstsneeseese 7,8
© This schematic diagram may be modified at any time with the development of new technology.
N
Bsn, : Tone control switch (TONE -§L:DEFEAT, -:ON)
e S801 : Power “STANDBY © /ON” switch (POWER, STANDBY © /ON)
® $802 : Tape monitor switch (TAPE MONITOR)
© S804 : Input select switch (SELECTOR)
® VR201 : Volume control VR (VOLUME)
® VR202 : Balance control VR (BALANCE)
® VR301 : Tone control VR (BASS)
® VR302 : Tone control VR (TREBLE)
® 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.
No mark: Power ON
® Voltage and signal line
[———> __: Phono Signal (L-ch) Line
a : Rec Out Signal (L-ch) Line
pees © Positive Voltage Line
sssePenen - Negative Voltage Line
® Important safety notice:
Components identified by /\ mark have special characteristics important for safety.
Furthermore,
special
parts
which
have
purposes
of
fire-retardant
(resistors),
high-quality
sound
(capacitors),
low-noise
(resistors),
etc.
are
used.
When
replacing
any
of
components,
be
sure
to
use
only
manufacturer's
specified
parts
shown
in
the
parts
list.
®
Caution!
IC and LSI are sensitive to static electricity.
Secondary trouble can be prevented by taking care during repair.
Cover the parts boxes made of plastics with aluminum foil.
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.

Technics SE-A900S Specifications

General

Brand	Technics
Model	SE-A900S
Category	Amplifier
Language	English