Tapedeck Wiring; Variation Table For Analog Circuit; Tape Mechanism Electronics; Tape Adjustment And Check Table - Philips MC-50/22 Service Manual

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Tapedeck wiring (Single deck)
TO ETF6-FE BOARD 1760
REC
REC
REV
FWD
CRO2
MODE
SW
TO ETF6-LE BOARD
CONNECTOR 1710

TAPE MECHANISM ELECTRONICS

+
Motor
-
Photo Sensor
R1 = 680R
Rec/Pb Head wire
Head connector pcb
1. +L ch (White)
2. Earth (Black)
3. +R ch (Red)
4. E Head (Blue)
5. E Head (Yellow)
9-3

Variation table for Analog Circuit

Item No. Autoreverse (FR)
3723 12k
3724 12k
3743 1k2
3744 1k2
3769 12k
3772 4k7
3774 10k
Solenoid
_ +
TAPE DECK
MOTOR
NC
NC
8. Gnd
7. Mode SW
6. Vcc 12V
Mode
5. Sol.
CrO2
4. Photo Out
3. CrO2 SW
2. Rec SW Forward
1. Rec SW Reverse
Rec-F
Rec-R
Solenoid
TAPE ADJUSTMENT & CHECK TABLE
Non-Autoreverse (FF)
15k
15k
MOTOR SPEED
1k
1k
WOW & FLUTTER
8k2
5k6
ADJUST AZIMUTH
8k2
PLAYBACK LEVEL
& FREQ. RESPONSE
ADJUST BIAS
CURRENT
CHECK RECORD/PLAYBACK FREQUENCY AND DISTORTION
Inject 3mV signals
100Hz, 250Hz, 1kHz,
10kHz, 12.5kHz
via or
3 4
Inject 1kHz 8.85mV
via 3 or 4
SBC419A : 4822 397 30069
SBC420 : 4822 397 30071
level(dB)
80
9-3
TEST MEASURE
RECORDER
READ ON
CASSETTE
MODE ON
frequency
SBC420
PLAY
counter
3150Hz
SBC420
PLAY W&F-meter
3150Hz
or
1 2
PLAY FWD
SBC420
LEFT RIGHT
mV-meter
10kHz
PLAY REV ^
SBC420
PLAY mV-meter
315Hz
SBC419A
or 6
5
mV-meter
RECORD
SBC420
LEFT RIGHT
SBC419A
or RECORD B
SBC420
RECORDED
1 or 2
PLAY B mV-meter
CASSETTE
LEFT RIGHT
SBC419A
or
RECORD B
SBC420
RECORDED or
1 2
PLAY B THD-meter
CASSETTE
LEFT RIGHT
^ For Auto-reverse version only
* If high frequencies are not within limits, decrease bias and re-measure.
If distortion is too high, increase bias and re-meaure
level(dB)
8dB
6dB 8dB
f(Hz)
250
4k 12.5k 100
figure. 1
It`s Free
ADJUST
with to
check 3150Hz +/- 2%
check
< 0.4 % DIN
left hand screw
max. output level
& left=right
right hand screw
125mV +/- 3dB
(see fig.1 for freq.
check
response)
3773 995mV
check
750mV +/- 1.5dB
check limits see fig. 2 *
check < 3% *
8dB
6dB 8dB
f(Hz)
250
4k 10k
figure. 2