GB Adjustment Procedures, Main Board | Grundig Aura instruction

AURA	Abgleichvorschriften / Adjustment Procedures

GB Adjustment Procedures

1. Main Board

Test equipment: DC Voltmeter, Test Generator, AF Voltmeter, Stereo Coder, Sweep Generator, Oscilloscope

Calling up the ´extended Expert Mode´:

Switch off the set. Press and hold depressed station button 2 and switch on the set. Hold the station button 2 depressed for more than 10 seconds. Press and hold depressed the TAPE/CD button for about 5 seconds until the display shows SE-XX-MC(XX = Version of software). Press button TP/AS for more than 5 seconds until after the second sound. With the buttons < resp. > select the corresponding parameter set (display shows e.g. 00 1400). Press button TP/AS briefly (additional E in the display: E 00 1400). With the buttons < resp. > change the value. Press button TP/AS briefly (E goes out).

If you changed an other parameter by mistake you can find its correct value in the parameter table on page 9.

Leaving the ´extended Expert Mode´:

Switch off the set.

Adjustment

Preparation

Adjustment Procedure

1. MW Oscillator

MW;

Align with L606A at 531kHz for 1.0V ± 50mV.

Connect a DC Voltmeter to FMP705.

Check for 7.0V ± 0.5V at 1602kHz.

2. LW Oscillator

LW;

Align with L607AL at 153kHz for 1.3V ± 50mV.

Connect a DC Voltmeter to FMP705.

Check for 5.0V ± 0.5V at 279kHz.

3. AM IF

Connect a Test Generator to aerial input; Frequency

Align with L604A for maximum voltage.

1548kHz; no modulation; E´ = 100μV (40dBμV).

Connect a DC Voltmeter to FMP602.

4. MW Bandpass

Connect a Test Generator to aerial input; no modulation;

Align alternating with C608A at 1548kHz and with L601A at

E´ = 100μV (40dBμV).

558kHz for maximum voltage.

Connect a DC Voltmeter to FMP602.

5. LW Bandpass

Connect a Test Generator to aerial input; no modulation;

Align with L602AL at 162kHz for maximum voltage.

E´ = 100μV (40dBμV).

Connect a DC Voltmeter to FMP602.

6. AM search level

Connect a Test Generator to aerial input; Frequency

stop

1008kHz; no modulation;

Call up the extended expert mode (see above).

Apply a signal with E´ = 250μV (48dBμV). Set DX to OFF.

Change Parameter value 01 until search just stops.

Apply a signal with E´ = 20μV (26dBμV). Set DX to ON.

Change Parameter value 00 until search just stops.

7. FM Oscillator

FM;

Align with L06 at 87.5MHz for 1.6V ± 50mV.

Connect a DC Voltmeter to FMP705.

Check for 6.5V ± 0.5V at 108MHz.

8. FM RF and IF

Connect a Test Generator to aerial input; Frequency

95.0MHz; no modulation; E´ = 100μV (40dBμV).

Align alternating with L03 and L04 for maximum.

Connect a DC Voltmeter between FMP101 (+) and

Align with L05 for maximum.

FMP103 (-).

9. IF Center fre-

Connect a Test Generator to aerial input; Frequency

quency

98.0MHz; fmod = 1kHz; Hub = 22.5kHz; E´ = 1mV (60dBμV).

Connect an AF Voltmeter to FMP101.

Call up the extended expert mode (see above).

Select parameter 48.

Set the parameter value for minimum AF voltage.

10. Stop Generator

Connect a sweep generator to aerial input. Center fre-

Align L 101 for a symmetrical stop impulse.

quency 95.0MHz; Δf = ± 100kHz; no modulation;

95.0MHz

E´ = 100μV (40dBμV);

+5V

Connect an Oscilloscope to FMP104.

Δf≤ ± 45kHz

11. Field strength

Connect a Test Generator to aerial input; Frequency

Adjust with CR26 for +300mV ± 10mV.

95.0MHz; no modulation; E´ = 70μV (37dBμV).

Connect a DC Voltmeter between FMP101 (+) and

FMP103 (-).

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