Grundig GV 440 NIC Servicehandbuch Seite 92

Abgleichvorschriften / Adjustment Procedures
2.6 Family Board – FM Sound (AF)
Test Equipment: Oscilloscope, 10:1 Test Probe, Frequency Counter, AF Generator, AF Millivoltmeter, Test Cassette (HiFi).
Service work after changing the:
... Family Board, the Tape Drum / Headwheel: Adjustment no. 1...4
... IC7320: Adjustment no. 1...4
Adjustment
1. Carrier Frequency Frequency counter: ............................................. MP
Load a cassette, call up the service function:
– Press the
(" CODE – – – – " is indicated in the display).
– Enter the code number
button (" SERV " is indicated in the display).
Do not feed in an AF signal! HiFi recording.
Left Channel
Press button
R3402 (CFL),
Right Channel
Press button
R3435 (CFR)
2. Playback Amplitu- AF millivoltmeter: .................................... Audio
de, R3390 (PBL) Play back the test cassette (HiFi).
3. Voltage of the FM- Oscilloscope: ...................................................... MP
Envelope, R3455 Play back the test cassette (HiFi).
(FME)
4. Voltage of the AF generator, 1kHz, 400...600mV
Sound Envelope Oscilloscope: ........................................... Audio
Manual control of the HiFi recording:
Press the
Q
set the audio output levels
Left Channel Oscilloscope: ...................................................... MP
R3385 (AEL),
Right channel
Oscilloscope: ...................................................... MP
R3380 (AER)
2.7 Family Board – Standard Sound / Audio Linear (AL)
Test Equipment: Oscilloscope, 10:1 Test Probe (TK), Frequency Counter, AF Millivoltmeter, AF Generator, Trademarked Chromium Dioxide Cassette.
Service work after replacing the Family Board or the RP-Head: Adjustment no. 1...4
Adjustment
1. Sound Erase Frequency counter, 10:1 test probe: .................. MP
Frequency, Record
F1055 (FAEH)
2. Full Track Erase Frequency counter, 10:1 test probe: .................. MP
Head, Record.
F1052 (FFEH)
3. Bias (VM), Oscilloscope, 10:1 test probe: ............................ MP
R3312 (BIAS) Record.
3.1 Frequency – Feed an audio signal of 10mV
Response Test generator to the socket Audio
the recorder).
– Make a recording at 400Hz and 8kHz, at least 1 min duration
of each frequency. Afterwards play back these recordings.
– Connect an AF millivoltmeter (oscilloscope) to EURO AV
socket pins 1 / 3 or Audio
4. Playback Level, AF generator, 333Hz / 0.5V
R3300 (LL)
AF millivoltmeter: .................................... Audio
HiFi-recording (automatic level control, Normal Play)
Play back this recording (switch over to standard sound).
3 - 8
Preparation
Z
button on the remote control handset
4 9 3 4
and press the
5 . The display shows " A 1-4 HI 00 00 A5 ".
. The display shows " A 1-8 HI 00 00 A6 ".
6
: .... Audio
rms
Ü
button on the recorder, with the buttons
L / R to 500mV
Preparation
(28mV
rms
L / R(on the rear side of
L / R.
: ................ Audio
rms
21
O
Set frequency with R3402 (CFL) to 1.4MHz
Set frequency with R3435 (CFR) to 1.8MHz
To cancel the service function: Press the "Standby" button
or disconnect the recorder from the mains.
L / R Set output voltage with R3390 (PBL) to 50mV
22
With R3455 (FME) set the voltage as shown in the oscillo–
gram below.
5ms/cm
L / R
L / R
W
.
rms
23
Set DC voltage with R3385 (AEL) to 1.5V.
24
Set DC voltage with R3380 (AER) to 1.5V.
13
Set frequency with F1055 (FAEH) between 59kHz and
65kHz.
14
Set frequency with F1052 (FFEH) between 59kHz and
65kHz.
13
With R3312 (BIAS) alter the voltage between 22V
62V until the frequency response is linear.
pp
) from the AF The voltage ratio of 400Hz to 8kHz must not be greater
pp
than 1:0.7 or 0.7:1 (±3dB). If the voltage ratio exceeds
these limits, the bias must be altered:
To increase the playback voltage at 8kHz: Reduce bias (VM).
To reduce the playback voltage at 8kHz: Increase bias
(VM).
L / R Set output voltage with R3300 (LL) to 0.5V
L / R
GV44..., GV45..., GV46...
Adjustment Procedure
±
5kHz.
±
5kHz.
±
rms
2.9V
Adjustment Procedure
.
rms
GRUNDIG Service-Technik
0.5dB.
and
pp