Grundig M 28-C Servicehandbuch Seite 35

M 18-C ... M 48-DC
2. Tape Decks
Measuring instruments/Test equipment:
AF voltmeter, Frequency counter, AF generator, test cassette 448A Part No.: 35079-023.00
Alignment
1. Azimuth Remove the cassette lid cover (disassembly instructions
para 5). The adjustment screws can now be set through the
holes in the cassette lid.
Tape, Cr
Playback the test cassette 448A sound part 10kHz.
AF voltmeter to
2. Speed Tape, Cr
Put empty cassette in tape 2
Playback the test cassette 448A in tape 1, sound part
3150Hz
Frequency counter to
High Speed Dubbing
Normal Speed Dubbing
3. Playback level Tape, DOLBY NR off, Cr
Playback the test cassette 448A sound part 315Hz
AF voltmeter to
4. Bias Tape 2, Record, test cassette 448A side B, Cr
AF voltmeter between Pin 1 and 2
4 of 1711
12
5. Record level Tape2 ; DOLBY off, test cassette 448A side B, Cr, Record
AUX
Short circuit
Connect AF generator 330Hz to AUX inputs
AF voltmeter to
AF voltmeter between Pin 1 and 2
4 (L) of 1711
12
1742
1741
1
8
1
3682 3684
1
GRUNDIG Service
Preparation
resp.
10 11
resp.
10 11
(L) and (R)
10 11
resp. Pin 3 and
13
to GND
16
resp.
14 15
(R) resp. Pin 3 and
13
etf2-p2-951114-1
3139 113 33192
1704
1 1
normal
With the corresponding adjustment screws set the left and
right channel to maximum.
With 3682 set to 5670Hz
With 3684 set to 3150Hz
Tape 1:
With 3635 (L) set 675mV
With 3636 (R) set 675mV
Tape 2:
With 3641 (L) set 675mV
With 3642 (R) set 675mV
With 3773 and 3785 set alternating to 110mV
both channels
With generator output set to 170mV
With 3655 (R) resp. 3656 (L) set 5mV
16
3785
3773
12 13
4 1
1711
1 1
1706
Abgleichvorschriften / Adjustment Procedures
Procedure
reverse
±
0.5%.
±
0.5%.
±
0.5dB
±
0.5dB
±
0.5dB
±
0.5dB
±
5mV in
rms
±
0.5dB
11
1701
7
15
2696
2695
5632
5631
10
1
14
3 - 4