Grundig CDM 800, Руководство по обслуживанию

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2 - 4 GRUNDIG Service
Abgleichvorschriften / Adjustment Procedures CDM 800
Adjustment Procedures
1. Tuner
Measuring Instruments: Signal generator, Sweep generator, Oscilloscope, Digital voltmeter.
Adjustment Preparation Adjustment Process
1. AM IF
2. MW Oscillator
3. MW Aerial
bandpass
4. FM IF
5. FM Oscillator
6. FM Aerial
bandpass
7. 19kHz Filter
Adjust to
maximum with T101.
At
522kHz adjust to 1.7V
±
0.1V with T163.
Check: At 1611kHz <10V.
At
588kHz
adjust to
maximum with L110 (move MW aerial
coil).
At
1440kHz
adjust to
maximum with TC161.
Repeat this adjustment alternately.
Adjust to
maximum with T100.
At
87.5MHz adjust to 2.7V
±
0.1V with L101 (bend).
At
88MHz adjust to maximum with L102 (bend).
At
106MHz adjust to maximum with TC101.
Repeat this adjustment alternately.
Adjust to
minimum with T103 (left channel) and T104
(right channel).
Couple in a
sweep signal of 450kHz to L110 (ferrite aerial)
via a loop aerial.
Oscilloscope to testpoint TP4 (IC102 Pin 18).
Band switch: MW
MW, 522kHz
Digital Voltmeter to Testpoint TP3 (C104).
Band switch: MW
MW 588kHz, MW 1440kHz
Couple in a
standard signal to L110 (ferrite aerial) via a
loop aerial, f
mod
= 1kHz, m = 30%, U
a
as low as possible, so
that the signal is just visible.
Oscilloskope to AF output.
Band switch: MW
FM, 88MHz
Couple in a
standard signal to Testpoint TP1 (CN101A),
f
mod
= 1kHz,
∆
f = 22.5kHz, U
a
as low as possible, so that the
signal is just visible.
Oscilloskope to AF output.
Band switch: FM
FM, 87.5MHz
Digital Voltmeter to Testpoint TP3 (C104).
Band switch: FM
FM 88MHz, FM 106MHz
Couple in a
standard signal to Testpoint TP1 (CN101A),
f
mod
= 1kHz,
∆
f = 22.5kHz, U
a
as low as possible, so that the
signal is just visible.
Oscilloskope to AF output.
Band switch: FM
FM 88MHz
Couple in a
standard signal to Testpoint TP1 (CN101A),
f
mod
= 19kHz.
Oscilloskope to TP5 (left channel) and TP6 (right channel).
Band switch: FM
IC102
T163
TC161
T103 T104
CN101A
T101
FE101
C104
TP1
TP3
Pin19/TP2
Pin18/TP4
TP5 TP6
CD80-01-09
CN102 CN101
L101
IC101
TC101
L102
T100