Troubleshooting
GV 900…, GV 940…
k
3 - 16
GRUNDIG Service
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Troubleshooting Diagram 21 – IN/OUT
Output
Input Signal from
Output signal to
Mono
Switch Setting IC2501
Input
IC701-(47), video output
E2 -(20), video input
Pin 19
Pin 18
Pin 20
E1-(19), video output
IC201-(11), audio output
E2-(2, 6), audio input
Pin 36
Pin 1
Pin 35
E1-(1, 3), audio output
Q1612, Tuner-video output
E1-(20), video input
IC701-(47), video output
Pin 16
Pin 14
Pin 19
Pin 23
E2-(19), video output
Q1605, Tuner audio output
E1-(2, 6), audio input
IC201-(11), audio output
Pin 9
Pin 5
Pin 36
Pin 29
E2-(1, 3), audio output
E2 -(20), video input
E1-(20), video input
Q1612, Tuner video output
Pin 18
Pin 14
Pin 16
Pin 21
IC201-(31), video input
E2-(2, 6), audio input
E1-(2, 6), audio input
Q1605, Tuner audio output
A
B
A
B
A
B
C
A
B
C
A
B
C
A
B
C
Pin 1
Pin 5
Pin 9
Pin 31
IC201-(9), audio input
NO
NO
NO
YES
YES
YES
Power supply STBY5V?
Power supply STBY10.5V?
Signal path between IC2501-(25, 26)
and IC701-(17, 18)?
SDA and SCL signals at
IC2501-(25, 26)?
5V at IC2501-(15, 17)?
(for video section)
10.5V at IC2501-(8, 10)?
(for audio section)
Check the video and audio signal
paths according to the funciton
logic table below.
No Video and Audio Signal
at Euro-AV Socket
HiFi Stereo
Note:
Euro-AV socket E1:
Input and output
Euro-AV socket E2:
Input; output only
for decoder operation
Switch Setting IC2501
Input Signal from
Input
Output
Output Signal to
IC701-(47), video output
E2 -(20), video input
Pin 19
Pin 18
Pin 20
E1-(19), video output
IC6301-(58), audio output left
E2-(6), audio input left
Pin 36
Pin 1
Pin 35
E1-(3), audio output left
LINE output left
IC6301-(56), audio output right
E2-(2), audio input right
Pin 33
Pin 3
Pin 32
E1-(1), audio output right
LINE output right
Q1612, Tuner video output
E1-(20), video input
IC701-(47), video output
Pin 16
Pin 14
Pin 19
Pin 23
E2-(19), video output
Stereo/Nicam Decoder output left
E1-(6), audio input left
IC6301-(58), audio output left
Pin 9
Pin 5
Pin 36
Pin 29
E2-(3), audio output left
Stereo /Nicam Decoder output right
E1-(2), audio input right
IC6301-(56), audio output right
Pin 11
Pin 7
Pin 33
Pin 28
E2-(1), audio output right
E2-(20), video input
E1-(20), video input
Q1612, Tuner video output
Pin 18
Pin 14
Pin 16
Pin 21
IC201-(31), video input
E2-(6), audio input left
E1-(6), audio input left
Stereo /Nicam Decoder output left
Pin 1
Pin 5
Pin 9
Pin 31
IC6301-(61), audio input left
E2-(2), audio input right
E1-(2), audio input right
Stereo /Nicam Decoder output right
A
B
A
B
A
B
A
B
C
A
B
C
A
B
C
A
B
C
A
B
C
A
B
C
Pin 3
Pin 7
Pin 11
Pin 30
IC6301-(52), audio input right
YES
YES
NO
NO
NO
NO
Troubleshooting Diagram 20 – Standard Sound
Signal path AUDIO_MUTE_(H) from
IC701-(21) to IC201-(9)?
Low signal at IC201-(99)?
Audio signal at IC201-(4)?
IC201?
YES
YES
NO
Erase oscillator (T651, Q651, Q652)
and A/C head?
Power supply M12V?
Peripheral circuit of T651,
A_ERASE_BIAS_CTL IC651-(4)?
Standard Sound Error
(HiFi - E-to-E mode is o.k.)
12V at T651, contact 2?
YES
Erase voltage at T651, contact 5?
Record signal (Bias+Audio)
at T651, contact 6?
Plug-in connection MH-AA?
A/C head?
YES
YES
NO
NO
Troubleshooting Diagram 19 – HiFi Sound 2
Playback envelope (ca. 0.3Vpp)
at output IC6301-(19)?
Signal path between
IC6301-(35) and IC701-(26)?
IC6301-(17) High? IC6301?
Signal path between headwheel
and IC6301, IC6301?
Head switching pulse (A-H.SW.P.)
at IC6301-(35)?
Playback of HiFi Sound not possible
(E-to-E mode is possible)
S. / P.
IC201
4-26
IC202
4-26
IC651
4-25
IC701
4-22
IC702
4-21
IC703
4-22
IC704
4-22
IC705
4-22
IC801
4-21
IC901
4-28
IC902
4-28
IC1601
4-33
IC1602
4-29
IC1701
4-36
IC1801
4-22
IC1901
4-35
IC1951
4-35
IC2501
4-24
IC5301
4-31
IC6301
4-24
RMC801 4-21
Tuner
4-30
