Grundig PA 1 User Manual

2 - 3 GRUNDIG Service
Abgleichvorschriften / Adjustment Procedures PA 1
Adjustment Preparation Adjustment Procedure
1. AM Oscillator
2. AM IF
3. AM RF circuit
4. FM Oscillator
5. FM IF
6. FM RF circuit
7. Stereo decoder
AM
Digital voltmeter to testpoint A.
AM, 603kHz
Test generator 603kHz to ferrite antenna (see Fig. 1).
f
mod
= 1kHz, m = 0.3.
AF voltmeter to Loudspeaker connector.
AM
Test generator to ferrite antenna (see Fig. 1). f
mod
= 1kHz,
m = 0.3.
AF voltmeter to Loudspeaker connector.
FM
Digital voltmeter to testpoint A.
FM, 88MHz
Sweep generator 88MHz to antenna connector (see Fig. 2).
Level <, ∆f = ± 200kHz,
Oscilloscope via 0.5pF to IC101, Pin 12.
FM
Test generator to antenna connector (see Fig. 2). Level <,
f
mod
= 1kHz, dev. 22.5kHz.
AF voltmeter to Loudspeaker connector.
FM, 88MHz
Stereo coder 88MHz to antenna connector (see Fig. 2).
Left channel modulated. Level 1mV / 75Ω, f
mod
= 1kHz, dev.
22.5kHz, pilot dev. 6.5kHz.
AF voltmeter to Loudspeaker connector, right chan-
nel.
At 603kHz adjust F109 to 1.75V ± 0.1V.
At 1404kHz check for < 6.7V.
Adjust F104 to maximum level.
Adjust alternating with F105 at 603kHz and with CT103 at
1404kHz for maximum level.
At 88MHz adjust L103 to 2.6V ± 0.1V.
At 106MHz check for < 5.9V.
Adjust with F108 and F103 for maximum and symmetry.
Adjust alternating with L102 at 88MHz and with CT102 at
106MHz for maximum level.
Adjust R124 for minimum.
Control the left AF output with the right channel modulated.
Crosstalk value should be > 20dB.
GB
Adjustment Procedures
Tuner:
Test Equipment:
Sweep generator, Test generator, Stereo coder, Oscilloscope, Digital voltmeter, AF Voltmeter
Cassette:
Test Equipment:
AF voltmeter, Frequency counter, Test Cassette 449 (Part No. 35079-019.00)
Adjustment Preparation Adjustment Procedure
1. Azimuth
2. Tape speed
AF voltmeter to Loudspeaker connector.
PlayTest Cassette 449 (8kHz part).
Frequency counter to Loudspeaker connector.
PlayTest Cassette 449 (3150Hz part).
With screw A adjust for maximum level.
A
With Motorpoti adjust for 3150Hz.
Motorpoti

Grundig PA 1 Specifications

General

Brand	Grundig
Model	PA 1
Category	Stereo System
Language	English