Fiat AD 185 M, Руководство по обслуживанию

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Abgleichvorschriften / Adjustment Procedures AD 185 M
4 GRUNDIG Service
GB
Adjustment Procedures
Test equipment: Digital Voltmeter, AF Voltmeter, Test Generator, Sweep Generator, Stereo Coder, Frequency Counter, Test Cassette 448A
1. Main Board
Adjustment Preparation Adjustment Procedure
Tape Speed Adjust with motorpoti for 3150Hz. Connect a Frequency Counter to Speaker Output.
Play Test Cassette 448A (3150Hz part).
2. Tape Drive
Align alternating with C641 at 1602kHz for 8.0V
±
50mV
and with L612 at 531kHz for 1.2V
±
50mV.
At 153kHz align with L613 for 1.0V
±
50mV.
Check at 279kHz for 4.5 - 5.0V.
Align with L611 for maximum.
Align alternating with L603 at 558kHz and with C606 at
1548kHz for maximum.
Align alternating with L604 at 162kHz and with C607 at
261kHz for maximum.
Connect FMP766 and +5V, Display shows INIT.
Press any station button, Display shows LEVEL M 2 resp.
LEVEL L 2.
Disconnect FMP766 and +5V.
Press any station button, Display shows LEVEL M 1 resp.
LEVEL L 1.
Press any station button, Display shows frequency.
Align with L04 for 2.2V
±
50mV.
Align alternating with L01, L03 and L101 for a maximum.
Align L102 for a symmetrical stop impulse.
88,0MHz
+5V
0V
∆
f
≤ ±
45kHz
Align R113 for +350mV
±
10mV.
Modulate the left channel and set R204 for maximum
Crosstalk Attenuation at the right channel.
Now modulate the right channel and look at the left
channel. If the difference is > 3dB, set R204 for equal
attenuation.
Connect FMP766 and +5V, Display shows INIT.
Press any station button, Display shows LEVEL U 2.
Disconnect FMP766 and +5V.
Press any station button, Display shows LEVEL U 1.
Press any station button, Display shows frequency.
1. MW Oscillator
2. LW Oscillator
3. AM IF
4. MW Band Pass
5. LW Band Pass
6. AM Search Level
7. FM Oscillator
8. FM Band Pass and
IF
9. FM Stop Generator
10. FM Field Strength
Level
11. Stereo Crosstalk
Attenuation
12. FM Search Level
MW;
Digital Voltmeter to FMP601.
LW;
Digital Voltmeter to FMP601.
Test generator to Aerial Input. MW, Frequency 1548kHz,
no modulation, E´ = 40dB
µ
V = 100
µ
V.
Digital Voltmeter to FMP603.
Test generator to Aerial Input. MW, no modulation,
E´ = 40dB
µ
V = 100
µ
V.
Digital Voltmeter to FMP603.
Test generator to Aerial Input. LW, no modulation,
E´ = 40dB
µ
V = 100
µ
V.
Digital Voltmeter to FMP603.
Test generator to Aerial Input. MW resp. LW, no modula-
tion.
MW: Frequency 1008kHz, E´ = 20dB
µ
V = 10
µ
V
LW: Frequency 207kHz, E´ = 26dB
µ
V = 20
µ
V.
MW and LW: E´ = 48dB
µ
V = 250
µ
V.
FM, Frequency 88.0MHz.
Digital Voltmeter to FMP1.
Test generator to Aerial Input. FM, Frequency 88.0MHz,
no modulation. E´ = 40dB
µ
V = 100
µ
V.
Digital Voltmeter between FMP101 (+) and FMP104 (-).
Connect a Sweep Generator to aerial input, FM, Center
frequency 88.0MHz;
∆
f = 100kHz; E´ = 40dB
µ
V = 100
µ
V,
no modulation.
Connect an Oscilloscope to FMP103.
Test generator to Aerial Input. FM, Frequency 88.0MHz,
E´ = 40dB
µ
V = 100
µ
V, no modulation.
Digital Voltmeter between FMP101 (+) and FMP104 (-).
Test generator to Aerial Input. Frequency 88.0MHz,
f
mod
= 1kHz, deviation 22.5kHz, Pilot level 7.5kHz,
E´ = 60dB
µ
V = 1mV.
AF-Voltmeter to Loudspeaker Output left and right.
Test generator to Aerial Input. FM, Frequency 95.0MHz,
no modulation.
E´ = 20dB
µ
V = 10
µ
V.
E´ = 48dB
µ
V = 250
µ
V.
Adjustment Preparation Adjustment Procedure
Motorpoti