Grundig CCF-23 Servicehandbuch Seite 15

CCF 23
Adjustment
10.MPX-filter Connect the AF-generator to LINE IN sockets.
(19kHz stereo (f = 315Hz, f
1
pilot tone) AF-voltmeter to test point
Deck B point
Insert a recordable cassette,
Cr tape (IEC II), in Deck B.
Function: Record-Pause
11.Frequency AF-voltmeter to test point
response on point
Playback Insert test cassette 448 A.
Deck A/B Play back the 315Hz / 12.5kHz frequency recording on the
tape.
Dolby off
12.AF head current AF-voltmeter to test point
adjustment point
during recording Insert test cassette 448 A, side B (blank part), Cr IEC II or
Deck B similar tape.
AF-generator to LINE IN sockets.
V = 500mV, f = 400Hz.
i
Function: Record-Pause
13.Frequency AF-voltmeter to test point
adjustment point
during recording Insert test cassette 448 A, side B (blank part) Cr IEC II or
Deck B similar tape.
AF-generator to LINE IN sockets.
V = 500mV, f
i
Function: Record-Pause
14.Bias voltage AF-voltmeter with a 1:1000 capacitive voltage divider to
Deck B test point
and
respectively.
Insert a recordable cassette Fe or Cr.
Function: Record-Start.
15.Distortion factor AF-voltmeter to test point
Deck B point
Insert a recordable cassette, Fe or Cr tape.
AF-generator to LINE IN sockets.
V = 500mV, f = 333Hz.
i
Function: Record-Pause
GRUNDIG Service
Preparations
= 115mV ± 1.5dB).
= 19kHz, V
2 i
D1 (left channel) and test
D2 (right channel) respectively.
Dolby off
Level control to "maximum"
D1 (left channel) and test
D2 (right channel) respectively.
D1 (left channel) and test
D2 (right channel) respectively.
Dolby off
–
Record-Srart
–
Playback-Start
D1 (left channel) and test
D2 (right channel) respectively.
= 400Hz, f = 12.5kHz
1 2
Dolby off
–
Record-Start
–
Playback-Start
TP 5 (left channel, head connector P102/1)
TP 6 (right channel, head connector P102/6)
D1 (left channel) and test
D2 (right channel) respectively.
Dolby off
–
Record-Start
Set the LINE IN-level during Record-Pause so that at
315Hz the voltage measured at the test points
D2 is V = 388mV (= 0dB).
o
At 19kHz = V
10 k
Adjust with F103 (left channel) or F104 (right channel).
≈
10 k
LINE IN
Deck B:
If the levels V
D2 differ by more than ± 1.5dB cut the bridges B1
(C103), B2 (C107) left channel, and the bridges B3
(C104), B4 (C108) right channel respectively.
Deck A:
If the levels V
D2 differ by more than ± 1.5dB cut the bridges B5
(C109), B6 (C114) left channel, and the bridges B7
(C111), B8 (C115) right channel respectively.
V f (12.5kHz)
o 2
V f (315Hz)
o 1
With the level control (RECORD LEVEL) set the level at
the test points
On playing back the recording made on the cassette recorder,
a voltage level of 120mV ±0.5dB must be present at the test
points D1 and
10 k
If the level differs from the value above re-adjust the head
≈
10 k
LINE IN
current control R232 (left channel) or R233 (right channel)
during recording.
When recording on Fe IEC I-cassettes the voltage must be
120mV ±1dB.
With the level control (RECORD LEVEL) set the level at the
test points
When playing back the recording the levels at the test
points D1 and
If V f to V f
o 2 o 1
Re-adjust with R296 left channel, and R295 right channel
respectively.
V f (12.5kHz)
o 2
V f (400Hz)
o 1
The bias voltage depends on the type of tape and the
frequency response setting.
Adjustment range:
Fe = 10 - 15V
CrO = 18 - 25V
2
With the level control (RECORD LEVEL) set the level at the
test points
Distortion analyzer to LINE OUT L or LINE OUT R sockets
(47kΩ termination).
10 k
Function: Playback-Start
≈
10 k
LINE IN Dolby off
Distortion factor measured at the LINE OUT sockets at
47kΩ on playing back the made recording:
Fe IEC I
CrO IEC II K
2
Einstellvorschriften / Adjustment Procedures
Adjustment Procedure
≤
12mV (≤ –30dB).
o
f (315Hz) and V f (12.5kHz) at
o 1 o 2
f (315Hz) and V f (12.5kHz) at
o 1 o 2
= +1 ± 0.5dB
D1 and D2 during recording to 120mV.
D2.
D1 and D2 during recording to V
D2 must not differ by more than 0.5dB.
is higher than 0.5dB correct the bias.
= 0dB ± 0.5dB
D1 and D2 during recording to V
≤ 1.5%
K
3
≤ 2.0%
3
D1 and
D1 and
D1 and
= 22mV.
o
= 388mV.
o
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