Technics ST-G3

@ DESCRIPTION OF LCD PANEL
e COMMON
e SEGMENT
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TUTTITTEIrrrirrir
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SS. PEEPLP PEPE EE EERE PEPER
< Segment ON >
Pin @ or @ of LCD and each segment terminal.
< Segment OFF >
Pin @ or @ of LCD and each segment terminal.
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2V AC/DIV, 5m sec/cm
e Each segment waveform measuring method
Note: Potential difference from COM terminal waveform
is measured for each segment output waveform.
So, do not connect the earth to other equipment on
the oscilloscope side.
If the earth is connected,
2V AC/DIV, 5m sec/cm
Oscilloscope
Connect it to each COM
terminal (probe) of 1C901.
Connect it to each
segment terminal
of 1C901.
{C901 will break down.
@ TERMINAL GUIDE OF TRANSISTORS, IC’S AND DIODES
2SA564, 250945
2801815
AN7274NS
28Pin
AN7472S-A
HPDITMGSIIA | 64Pin
SVDKV 12362
MA4062, MA4082,
MA4150
Al yy
KI A2Ke
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ST-G3
ST-G3
™@ FUNCTION OF TERMINAL (IC901: uPD1714G511)
IN/OUT
Description of terminal
Ground terminal.
OUTPUT
Not used in this unit.
EO2
The frequency is output as a result of comparison between LCD frequency and FM or AM
station frequency.
Ground terminal.
(INPUT
AM
Input for AM OSC output.
1.87V
|
of (eS
522kHz 1629kHz
Input for FM OSC output frequency divided to 1/32 or 1/33 by pre-scaler.
INPUT
cE
Power supply detection.
OUTPUT
MUTE
“H” input with it connected to home-use power outlet socket,
H— 4v, L—O0V
Ground terminal.
This is the output terminal to eliminate shock noise
due to unlocking at PLL.
4.8V
<Muting output > y
1. Pin 7 (CE) is L—*H or H—*L. a
2. Power switch “off”.
3. Frequency change. (up/down, FM «AM, REC).
4, FM IF selection.
Muting output operation
Not used in this unit.
INPUT STEREO
H (4.8V) —*AM
AM selector.
Not used in this unit.
Stereo indicator drive.
L (0) — Stereo indicator light up.
INPUT
sD
OUTPUT
MONO
STANDBY
so
OUTPUT
INPUT
xX OUT
Xx IN
26
28 ~ 39
40 ~55
58
INPUT
OUTPUT
OUTPUT
Vpp
Station detection
1, Signal received —> H (5V)
2. NO signal —>L (OV)
Not used in this unit.
Forcible monaural selection,
4.7V
a any
Forcible monaural mode
Not'used in this unit.
Connecting terminal for crystal oscillator.
The crystal connected is at 4.6 MHz.
Power supply terminal. {4,7V)
CGP
$27 ~S16
—
OUTPUT
OUTPUT iceman Z Common of LCD.
$15 ~ SO
COM 1
Clock pulse waveform output,
Segment signal output for LCD display,
LCD seg
LCD seg : LCD display data
KS : Key source data
INPUT
Vv
DD
Power supply terminal, (4,7V)
59 ~62
INPUT
K3 ~KO
Input terminal for key return signal from external key matrix.
63
INPUT
SSL
Electromagnetic field intensity level input is changed from analog to digital.
64
INPUT
Interrupt requesting signal input terminal. Band det.
Signal from control input terminal is put 125 l J U l
into this terminal. Pet lec
: , c
Detected when input is "L”. id 18msec ~200msec get
625msec 580msec