Adjustment Procedures; Main Board - Grundig EC 4600 RDS Serviceanleitung

EC 4600 RDS

Adjustment Procedures

1. Main Board

Test equipment: DC Voltmeter, Test Generator, AF Voltmeter, Sweep Generator, Test Cassette 448A (Part-No 35079-023.00)
Adjustment
1. MW Oscillator MW;
Connect a DC Voltmeter to FMP639.
2. LW Oscillator LW;
Connect a DC Voltmeter to FMP639.
3. MW Band Pass Connect a Test Generator to aerial input; MW; Frequency
1404kHz; f
Connect an AF Voltmeter to Loudspeaker Output.
4. LW Band Pass Connect a Test Generator to aerial input; LW; Frequency
153kHz; f
Connect an AF Voltmeter to Loudspeaker Output.
5. AM IF Connect a Test Generator to aerial input; MW; Frequency
1008kHz; f
Connect an AF Voltmeter to Loudspeaker Output.
6. FM Oscillator FM;
Connect a DC Voltmeter to FMP24.
7. FM Stop Generator Connect a Sweep Generator to aerial input; FM; Center
frequency 93.5MHz; ∆f = 100kHz; E´ = 1mV (60dBµV); no
modulation.
Connect an Oscilloscope to FMP115.
8. FM Band Pass Connect a Test Generator to aerial input; Frequency
87.8MHz; f
Connect an AF Voltmeter to Loudspeaker Output.
8. FM IF Connect a Test Generator to aerial input; Frequency
93.5MHz; f
Connect an AF Voltmeter to Loudspeaker Output.
10. Field Strength Connect a Test Generator to aerial input; Frequency
Level 93.5MHz; no modulation; E´ = 100µV (40dBµV).
Connect DC Voltmeter between FMP121 (+) and
FMP122 (-).
11. Dolby Play Test Cassette 448A (315Hz Dolby part).
Connect AF Voltmeter to FMP1119 (left channel) resp.
FMP1124 (right channel).
2. Cassette Drives
Test equipment: AF Voltmeter, Frequency Counter, Test Cassette 448A (Sach-Nr. 35079-023.00)
Adjustment
1. Tape Speed Connect Frequency Counter to Loudspeaker Output.
Play Test Cassette 448A (3150Hz part).
GRUNDIG Service
Preparation
= 1kHz; m = 30%; E´ = 30µV (30dBµV).
mod
= 1kHz; m = 30%; E´ = 30µV (30dBµV).
mod
= 1kHz; m = 30%; E´ = 30µV (30dBµV).
mod
= 1kHz; dev. 22.5kHz; E´ = 3µV (10dBµV).
mod
= 1kHz; dev. 22.5kHz; E´ = 3µV (10dBµV).
mod
Preparation
Abgleichvorschriften / Adjustment Procedures
Adjustment Procedure
2
Align with L612 at 531kHz for 1.2V
±
Check at 1602kHz for 7.5V 0.5V.
3
Align with L613 at 135kHz for 1.0V
±
Check at 279kHz for 5.0V 0.5V.
4
Align with L603 for maximum AF Voltage.
5
Align with L604 for maximum AF Voltage.
1
Align with F601 for maximum AF Voltage.
7
Align with L04 at 93.5MHz for 2.85V
!
Align F105 for a symmetrical stop impulse.
93.5MHz
+5V
0V
∆f = ± 25kHz
0
Align alternating with L03 and L01
AF Voltage.
8
Align with F101 for maximum AF Voltage.
±
Align with CR105 for +425mV
Adjust CR1109 for the left channel resp. CR1133 for the
right channel for 490mV.
Adjustment Procedure
With Motorpoti adjust for 3150Hz.
±
20mV.
±
20mV.
±
20mV.
9
for maximum
20mV.
Motorpoti
PCB
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