EN-34
ISSUE
DRAWING NO.
DRAWING TITLE
DATE
Filename:
ECO No.
DESCRIPTION OF CHANGE
L281 CT9 Protection Circuitry.SchDoc
AMP019 Protection Circuitry
Contact Engineer:
L281CT
15/01/2021
INITIALS
Printed:
9
10
Sheet
of
Notes:
Contact Tel:
01223 203201
Jon Henderson
A & R Cambridge Ltd.
Cambridge CB25 9QE
Waterbeach
A3
ARCAM
63V
C8002
10UF
63V
C8003
10UF
DGND
D8001
BAV99
D8002
BAV99
D8000
BAV99
DGND
TR8000
MMUN2111LT1
0W063
R8003
4K7
DGND
DC OFFSET
DC OFFSET DETECTION
-14V
ERR +VE
ERR -VE
+3V3
0W125
R8011
3K9
TR8001
BC847B
TR8004
BC857B
P8001
P8015
P8003
P8014
P8008
P8002
P8017
P8004
0W125
R8001
100K
0W125
R8009
100K
+55V
SHORT L
SHORT SR
0W125
R8007
120K
TR8003
MMUN2211LT1
DGND
OVER CURRENT DETECTION
0W063
R8005
4K7
PA SHORT*
+3V3
SHORT R
SHORT SL
SHORT BL
SHORT BR
100V
C8001
100N
TR8002
MMBTA92L
DGND
P8009
P8012
P8007
P8005
P8011
0W125
R8002
10K
0W125
R8004
100K
0W125
R8006
100K
0W125
R8008
100K
0W125
R8010
100K
0W125
R8012
100K
0W125
R8013
100K
P8006
P8010
P8013
P8016
P8018
P8019
0W125
R8014
100K
P8020
SHORT C
ERR +VE
ERR -VE
SHORT L
SHORT R
SHORT SL
SHORT SR
SHORT BL
SHORT BR
SHORT C
DC OFFSET
PA SHORT*
63V
C8004
10UF
18_E035
JH
28/09/2018
E.0
No change to this sheet
18_E048
PK
28/11/18
F.0
No changes to this sheet
19_E027
JH
11/02/2019
1.0
No changes to this sheet
20_E002
PK
06/01/20
2.0
PCB change only
21_E001
PK
12/01/21
3.0
No change to this sheet
Summary of Contents for HDA PA720
Page 1: ...SERVICE MANUAL POWER AMPLIFIER PA720 ISSUE A ...
Page 2: ...EN 2 Revision History Issue A Initial release ...
Page 14: ...EN 14 EN 14 L281 Power Amplifier PCB Issue 3 ...
Page 36: ...EN 36 EN 36 L282 Pre amp PCB Issue 2 ...
Page 50: ...EN 50 EN 50 L283 PSU PCB Issue 1 ...
Page 54: ...EN 54 L284 Lifter PCB Issue 1 ...
Page 59: ...EN 59 L285 Front Panel PCB Issue 1 ...
Page 62: ...EN 62 Overall Dimensions ...
Page 64: ...EN 64 Exploded Drawings ...