Grundig R 23 DPL, Руководство по обслуживанию

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GRUNDIG Service 2 - 2
Abgleichvorschriften / Adjustment Procedures R 23 DPL
Adjustment Preperation Adjustment Procedure
1. Demodulator
2. Stereo Distortion
3. Stereo Crosstalk
4. Station search
5. 19/38 kHz Filter
FM, 98MHz
Test generator 98MHz to aerial socket;
U
RF
= 1mV / 75
Ω
,
∆
f = 22.5kHz.
Digitalvoltmeter to testpoint G (+/- CW603).
FM, 98MHz
Stereocoder, left channel modulated, to aerial socket;
98MHz,
∆
f = 40kHz,
±
6kHz pilot.
Distortion meter to AF output, left channel.
FM, 98MHz
Stereocoder, left channel modulated, to aerial socket;
98MHz,
∆
f = 40kHz,
±
6kHz pilot.
AF voltmeter to AF output, right channel.
FM, 98MHz
Stereocoder 98MHz to aerial socket;
U
RF
= 15
µ
V / 75
Ω
,
∆
f = 40kHz,
±
6kHz pilot.
FM
Test generator to aerial socket; FM, f
mod
= 38kHz.
AF voltmeter to AF output.
Adjust T601
C
to typ. 0V
±
50mV.
Adjust FE602
A
to K
min
(typ. 0.5%, max. 1%).
Control the right AF output with modulated right channel.
Adjust VR602
D
to minimum.
Control the left AF output with modulated right channel.
With VR601
B
adjust the search threshold (typ. U
RF
=
15
µ
V, max. U
RF
≤
20
µ
V) so that the „TUNED“ indication
still illuminates on the display.
Adjust T603
E
(left channel) and T604
F
(right channel)
to minimum.
©
Adjustment Procedures
Test Equipment:
Test Generator, Stereo Coder, Oscilloscope, Digital Voltmeter, AF-Voltmeter, Distortion Meter
Note:
The frontend is a completely preadjusted module. The values of the tuning voltages are:
87.5MHz = typ. 1.6V min. 1.3V
108MHz = typ. 8.3V max. 9.5V