Inhaltsverzeichnis
Werbung
Abgleichvorschriften / Adjustment Procedures
Tape Deck
Measuring instruments / equipment:
Frequency counter, AF voltmeter, AF generator, Wow and flutter meter, Cr test cassette, Torque test cassette.
Adjustment
1. Tape speed
Frequency counter to AUX OUT.
Insert test cassette.
Play back 3150Hz.
2. Take-up torque on
Load the torque test cassette.
Start
Function: Start.
3. Wow and flutter
Wow and flutter meter to AUX OUT.
Load test cassette.
Play back 3150Hz.
4. Head gap angle
Connect AF-voltmeter to AUX OUT L (left channel) or to
(Azimuth)
AUX OUT R (right channel).
Load test cassette, play back 10kHz.
E
5. Playback level
AF-voltmeter to test point
Reference tape
(right channel).
scanning
Insert test cassette.
(Dolby level)
Play back 315Hz (250nWb/m).
Dolby off.
6. Erase frequency
Frequency counter to test point
Insert a recordable cassette with CR tape (IEC II).
Function: Record-Start.
7. Erase current
AF-voltmeter to test point
Insert a recordable cassette with CR tape (IEC II).
Function: Record-Start.
8. Record blocking
Connect the AF-voltmeter to test point
circuits
or to test point
(bias filter)
board.
Insert a recordable cassette with CR tape (IEC II).
Function: Record-Start.
9. MPX-filter
Connect the AF-generator (f
(19kHz stereo pilot
AUX IN sockets.
tone)
Close wire bridge B407.
Connect the AF-voltmeter to the
test points
or
D2 (right channel).
Insert a recordable cassette with
CR tape (IEC II).
Function: Record-Start, Dolby off.
10.Frequency
AF-voltmeter to test point
response on
D2 (right channel).
Playback
Insert test cassette.
Play back the 250Hz / 12.5kHz frequency recording on the
tape.
Dolby off
Dolby noise reduction under license from Dolby Laboratories Licensing Corporation.
„DOLBY" and the double D Symbol
NR = Noise Reduction.
2 - 5
Preparations
Tape run
Tape run
"Normal"
"Reverse"
D1 (left channel) or
L1 (R263).
L1 (in parallel with R263).
TP3 (left channel)
TP4 (right channel) on the audio circuit
= 315Hz, f
= 19kHz) to the
1
2
D1 (left channel)
10 k
≈
10 k
D1 (left channel) or test point
are trademarks of Dolby Laboratories Licensing Corporation.
Adjustment Procedure
With adjustment control R482 (Logic board) set the fre-
±
quency to 3150Hz
1.0%.
On START, the torque should be 30 to 60 x 10
≈ 40g-cm.
≤
Deviation
0.1% (IEC wtd).
Playback measuring time ≥ 30 seconds.
Tape direction: "Normal"
With the head adjustment screw E set the left or right
channel to maximum level.
Then connect the left channel in parallel with the right
channel (AUX OUT). By minimum readjustment of the head
adjustment screw E set the output level to maximum.
Turn around the test cassette.
Tape direction: "Reverse"
Adjustment with head adjustment screw F for the same
F
level as in the "Normal" tape direction.
D2
Set the playback level with the adjustment controls R135
(left) resp. R136 (right) to 490mV
When using a test cassette with 200nWb/m set the playback
±
level to 388mV
0.5dB.
The oscillator frequency should be 85kHz
Adjust with L111.
Erase current: 150mA
±
= 150mV
10%.
Adjust for minimum RF with F111 at test point
channel) and F112 at test point
Set the input level during Record so that at 315Hz the
voltage measured at the test points
388mV (= 0dB).
≤
At 19kHz: U
12mV (≤ –30dB).
o
Adjust with F101 (left channel) resp. F102 (right channel).
AUX IN
Open wire bridge B407.
If the levels between V
D1 and
D2 differ by more than + 1.5dB cut the bridges
B1 (C101), B2 (C103) left channel, or the bridges B3
(C102), B4 (C104) right channel.
V
f
(12.5kHz)
o
2
= 0 ± 0.5dB
V
f
(250Hz)
o
1
PA 6
-4
Nm
±
0.5dB.
±
10kHz.
±
10% measured at R263
TP3 (left
TP4 (right channel).
D1 and
D2 is
f
(250Hz) and V
f
(12.5kHz) at
o
1
o
2
GRUNDIG Service
Werbung
Inhaltsverzeichnis
