EC 4000 RDS
Abgleichvorschriften / Adjustment Procedures
GRUNDIG Service
2 - 2
GB
Adjustment Procedures
1. Electrical Adjustment
Test equipment: DC Voltmeter, Test Generator, AF Voltmeter, Stereo Coder, Sweep Generator
Adjustment
Preparation
Adjustment Procedure
Tape Speed
Connect Frequency Counter to Loudspeaker Output.
Play Test Cassette 448A (3150Hz part).
With Motorpoti adjust for 3150Hz.
Motorpoti
2. Adjustment of Cassette Drive
Test equipment: Frequency Counter, Test Cassette 448A (Sach-Nr. 35079-023.00)
1. MW Oscillator
2. LW Oscillator
3. MW Band Pass
4. LW Band Pass
5. AM IF
6. FM Oscillator
7. FM Stop Generator
8. FM Band Pass
9. FM IF
10. Field Strength
Level
Adjustment
Preparation
Adjustment Procedure
MW;
Connect a DC Voltmeter to FMP639.
LW; Frequency 153kHz.
Connect a DC Voltmeter to FMP639.
Connect a Test Generator to aerial input; MW; Frequency
1404kHz; m = 0.3; f
mod
=1 kHz; E´
≈
30
µ
V (30dB
µ
V).
Connect AF Voltmeter to Loudspeaker Output.
Connect a Test Generator to aerial input; LW; Frequency
153kHz; m = 0.3; f
mod
=1 kHz; E´
≈
30
µ
V (30dB
µ
V).
Connect AF Voltmeter to Loudspeaker Output.
Connect a Test Generator to aerial input; MW; Frequency
1008kHz; m = 0,3; f
mod
= 1kHz; E´
≈
30
µ
V (30dB
µ
V).
Connect AF Voltmeter to Loudspeaker Output.
FM;
Connect a DC Voltmeter to FMP24.
Connect a Sweep Generator to aerial input; FM; Center
frequency 93.5MHz;
∆
f = 100kHz; E´
≈
1mV (60dB
µ
V); no
modulation.
Connect an Oscilloscope to FMP107.
Connect a Test Generator to aerial input; Frequency
87.8MHz; f
mod
= 1kHz; dev. 22.5kHz; E´
≈
3
µ
V (10dB
µ
V).
Connect AF Voltmeter to Loudspeaker Output.
Connect a Test Generator to aerial input; Frequency
93.5MHz; f
mod
= 1kHz; dev. 22.5kHz; E´
≈
3
µ
V (10dB
µ
V).
Connect AF Voltmeter to Loudspeaker Output.
Connect a Test Generator to aerial input; Frequency
93.5MHz; E´ = 100
µ
V (40dB
µ
V); no modulation.
Connect DC Voltmeter between FMP121 (+) and FMP122 (-).
Align with L 612 (2) at 531kHz to 1.2V
±
20mV.
Check at 1602kHz for 7.5V
±
0.5V.
Align with L 613 (3) at 153kHz to 1.0V
±
20mV.
Check at 279kHz for 5.0V
±
0.5V.
Align with L 603 (4) for maximum AF output.
Align with L 604 (5) for maximum AF output.
Align with F 601 (1) for maximum AF output.
Align with L 04 (7) at 93.5MHz for 2.85V
±
20mV.
Align F 105 (I) for a symmetrical stop impulse.
93,5MHz
+5V
0V
∆
f =
±
25kHz
Align alternating with L 03 (10) and L 01 (9) for AF
maximum.
Align with F 101 (8) for AF maximum.
Align with CR 105 (6) for +425V
±
20mV.
