VARICAP ALIGNMENT
FM RF
FM IF
VCO
AM IF
AM RF
3)
108MHz
87.5MHz
(65.81MHz)
87.5MHz
(65.81MHz)
87.5MHz
(65.81MHz)
279kHz
153kHz
1602kHz
531kHz
5130
check
5122
check
5123
check
8V –0.2V
4.3V –0.5V
(1.2V –0.5V)
8V –0.2V
1.1V –0.4V
8V –0.2V
1.1V –0.4V
1494kHz
558kHz
560kHz 5102
1500kHz
5103198kHz
1494kHz
558kHz
560kHz
1500kHz
198kHz
2106
5102
2106
3142 152kHz –1kHz
1)
98MHz
5112
MAX
FM
87.5 - 108MHz
(65.81 - 74, 87.5 - 108MHz)
LW
153 - 279kHz
MW
FM/MW/LW- version, 9kHz grid
531 - 1602kHz
1700kHz
530kHz
5123
check
8V –0.2V
1.1V –0.4V
1602kHz
531kHz
5123
check
6.9V –0.2V
1.1V –0.4V
108MHz
108MHz 2155
5131
MW
FM/AM-version, 10kHz grid
530 - 1700kHz
FM
MW
LW
98MHz, 1mV
continuous wave
450kHz
connect pin 6 of
IC 7101 (AM Osc.)
with 3.3k‰ to Vcc
Use Service Testprogram. By selecting the TUNER TEST test frequencies will be stored as preset frequencies automatically.
4
1
3
5
5
A
A
5119FM
10.7MHz, 45mV
continuous wave
2D
mod=1kHz
6f=–22.5kHz
1)
If sensitivity of frequency counter is too low adjust to max. channel separation
(input signal: stereo left 90% + 9%, adjust output on right channel to minimum)
ECO6, Sys + PA with frame aerial, 070799
TUNER ADJUSTMENT TABLE ( ECO6 FM/MW- and FM/MW/LW - versions with AM-frame aerial )
6f=–10kHz
V
RF
= 0.5mV
C
see
remark
2)
220R
100nF
36
IC 7101
220R
100nF
40
IC 7101
2141
shortcircuit
to block AFC
21
IC 7101
max.
symmetric
f
o
AM AFC
MW
C
continuous wave
V
RF
= 2mV
5111
5114
2
0 – 2 mV DC
0 – 3 mV DC
MW
4)
FM/MW/LW- and FM/MW-version
( 9kHz grid)
531 - 1602kHz
B
6f = –30kHz
V
RF
as low as
possible
max.
symmetric
f
o
MW
FM/AM-version, 10kHz grid
530 - 1700kHz
3)
2)
RC network serves for damping the IF-filter while adjusting the other one.
4)
Waverange Input frequency Input Tuned to Adjust Output Scope/Voltmeter
FM
87.5 - 108MHz
(65.81 - 74, 87.5 - 108MHz)
FM/MW-version, 9kHz grid
531 - 1602kHz
(as low as
possible)
TAPE ADJUSTMENT & CHECK TABLE
^ 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
PLAY
mV-meter
check
125mV +/- 3dB
(see fig.1 for freq.
response)
PLAYBACK LEVEL
& FREQ. RESPONSE
TEST
CASSETTE
RECORDER
MODE
MEASURE
ON
READ ON
ADJUST
with
MOTOR SPEED
SBC420
3150Hz
PLAY
frequency
counter
check
PLAY
PLAY FWD
PLAY REV ^
W&F-meter
mV-meter
left hand screw
right hand screw
max. output level
& left=right
WOW & FLUTTER
ADJUST AZIMUTH
3150Hz +/- 2%
< 0.4 % DIN
to
1
2
or
LEFT
RIGHT
Inject 3mV signals
100Hz, 250Hz, 1kHz,
10kHz, 12.5kHz
1
2
or
LEFT
RIGHT
Inject 1kHz 8.85mV
3
4
or
via
3
4
or
via
1
2
or
LEFT
RIGHT
RECORD
RECORD
PLAY
PLAY
mV-meter
THD-meter
check
check
limits see fig. 2 *
< 3% *
RECORDED
CASSETTE
RECORDED
CASSETTE
figure. 1
f(Hz)
level(dB)
8dB
6dB
12.5k
4k
250
80
8dB
f(Hz)
level(dB)
8dB
6dB
10k
4k
250
100
8dB
figure. 2
check
SBC419A : 4822 397 30069
SBC420 : 4822 397 30071
SBC420
3150Hz
SBC420
10kHz
SBC419A
or
SBC420
SBC419A
or
SBC420
SBC420
315Hz
CHECK RECORD/PLAYBACK FREQUENCY AND DISTORTION
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