Service Manuals, User Guides, Schematic Diagrams or docs for : ARCAM A28 Arcam-A28-int-sch
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ITEM QTY PART No. DESCRIPTION NOTES
ITEM100 1 L991PB Blank PCB A28 Power Supply And Amplifier
ITEM102 1 8M101 Earth Lead Assy 75MM - This part is RoHS compliant. Soldered to SKT200
ITEM103 4 F232 13/16 inch O-Ring Rubber O-Rings fitted over UPPER HALF of amp supply caps (C228 - C231)
Placed on top of: output relays (RLY100, RLY101), mains relay (RLY200),
ITEM104 6 E827AP Pad Damping 15x6x3MM Rubber
output chokes (L100, L101) and preamp mute relay (RLY300)
LS100 Left Outputs
FD100 FD101 G P PRECISION
ANNOTATION
R100
+45V_L GENERAL NOTES
5R6
Power Amp Left
2W
L991CT4_2.2.SCH
CF This is the Master Schematic for A28 (L991AY) and P28 PCB
+45V_L
FIX100 FIX101 FIX102 FIX103 FIX104
RLY100A P102
assemblies. Any changes to the schematics in this document must be
Dia 3.5mm Dia 3.5mm Dia 3.5mm Dia 3.5mm Dia 3.2mm PRE_OUT_L VIPROT_L
L100
P100
G5PA-2 24VDC
Omron
reflected in the relevant child documents.
OUTPUT_L P103
1 P101 2U2
0V_FB_L
0V_FB_L
0V_LS_L
0V_HF_L
RLY101A When generating BOMs for L991AY, ensure that the relevant
C101
-45V_L
Omron components are fitted or not fitted (those with "NF" or "FIT" in the nearby text).
100N G5PA-2 24VDC
50V -45V_L
0805 0V_HF_L
0V_LS_L
These schematics follow a simple heirarchy scheme. Sheet symbols on the top
0V(D) sheet represent a child or sub-sheet. Net labels on sub-sheets are local or
Power Supplies
specific to that sheet. Ports on the sub-sheets connect to sheet entries on
LS101 Right Outputs
G P PRECISION
the parent sheet, where they are connected together.
Primary power nets are denoted by type in parenthesis, e.g. 0V(D).
+45V_R
R101 Secondary nets are denoted by underscores, e.g. 0V_LS_L.
5R6
Power Amp Right
2W
L991CT5_2.2.SCH
CF To perform an electrical rule check or synchronise with the PCB, set Net
+45V_R
Power Supplies
L991CT2_2.2.SCH
RLY100B
Identifier Scope to Sheet Symbols/Port Connections.
PRE_OUT_R VIPROT_R G5PA-2 24VDC
9VRMS L101
9VRMS P104 Omron
+4.8V(D)
+4.8V(D) OUTPUT_R RLY101B P105
PWR_ON 2U2
+45V_R
+45V_R 0V_LS_R
+45V_L 0V_FB_R
+45V_L 0V_FB_R 0V_HF_R
0V(D) Omron
0V(D)
0V_LS_L
0V_LS_L
-45V_R
G5PA-2 24VDC HEADPHONE OUTPUT & MUTE
0V_HF_L -45V_R (NF ON P28)
0V_HF_L
0V_FB_L 0V_HF_R
0V_FB_L NF
0V(SIG) 0V_LS_R
0V(SIG) R102 0R0
0V(SIG_2)
0V(SIG_2)
0W125 0805
0V_FB_R
0V_FB_R
0V_HF_R R105 R104 RLY102A
0V_HF_R
0V_LS_R 330R 330R R106 NEC
0V_LS_R
1W 1W 100R EB2-5NU
0V(PSU)
+45V_L CF CF 1W NF
+4.8V(D) CF R103 0R0
0V(D) NCL SKT100
-45V_L
-45V_L 0W125 0805
-45V_R
-45V_R RLY102B
A28/P28Protection & Micros R107 CL
-38V_VFD L991CT6_2.2.SCH CON100 CON101 100R NEC
-38V_VFD
FIL_1 Q106 1 1 Q113 1W EB2-5NU 2 L
FIL_1 OUTPUT_L
FIL_2 Q111 2 2 Q114 CF 3 R
FIL_2 OUTPUT_R
Q118 3 3 Q115 1
+15V(A) Q121 4 4 Q116 CR
+15V(A)
+5V(A) +45V_L Q125 5 5 Q117
+5V(A) +45V_L RLY102C D102
+45V_R
+45V_R NEC BAS16
-15V(A) +4.8V(D) AMP AMP NCR
-15V(A) +4.8V(D) EB2-5NU SOT-323
0V(D) CT CT HOSIDEN
0V(D) 0.38Hz_CLK
HLJ
PreAmp Controls
0V(SIG)
0V(SIG)
-45V_L
-45V_L
-38V_VFD
-38V_VFD
FIL_1
FIL_1
FIL_2 A28 Trigger, RC5 & P28 Sig Detect
FIL_2
A28 PreAmp L991CT7_2.2.SCH
SPKR2_ON
L991CT3_2.2.SCH TAPE_0
TAPE_0 SPKR1_ON +45V_L
TAPE_1
0V_PREOUT TAPE_1 +4.8V(D) REMOTE_P
TAPE_2
TAPE_2 PWR_ON 0V(D) REMOTE_N
VOL_SCLK
*PRE_MUTE
*PRE_MUTE 0V(SER)
VOL_SCLK
0V_SER
0V_CHASS TRIG_IN OUTPUT MUTING
0V(D) VOL_SDATA
0V_D_PRE VOL_SDATA 0.38Hz_CLK
*RESET *RESET
TAPE_0 LISTEN_0
TAPE_0 LISTEN_0 RLY100C RLY101C
TAPE_1 LISTEN_1
TAPE_1 LISTEN_1 PRE_OUT_L
TAPE_2 LISTEN_2
TAPE_2 LISTEN_2 0V_PREOUT D100 D101
+4.8V_D_PRE PRE_OUT_R 1N4003 1N4003
VOL_SCLK 0V(D)
VOL_SCLK 0V_D_PRE DO-41 DO-41
0V(SER) *PRE_MUTE Omron
0V_SER *PRE_MUTE Omron
VOL_SDATA VOL_*CS G5PA-2 24VDC
VOL_SDATA VOL_*CS G5PA-2 24VDC
VOL_*CS
VOL_*CS VIPROT_L
VIPROT_R
9VRMS
9VRMS
LISTEN_0
LISTEN_0 R108 220R TR100 TR101
LISTEN_1 SPKR2_ON
LISTEN_1 REMOTE_P BD179 BD179
LISTEN_2
LISTEN_2 REMOTE_N 0W25 MF TO-126 TO-126
TRIG_IN
+15V(A)
+15V(A) R109 220R
+5V(A) SPKR1_ON
+5V(A)
+4.8V_D_PRE 0W25 MF
*PRE_RLY R110 R112 R111 R113
0V(SIG) 220R 2K2 220R 2K2
0V(SIG)
0V(SIG_2) 0W25 0W125 0W25 0W125
0V(SIG_2)
-15V(A) MF 0805 MF 0805
-15V(A)
PRE_OUT_L
PRE_OUT_R R114
0R0
0W25
MF
+45V_L
0V(D)
Flexfoil
A28 & P28 Display Circuitry
L991CT8_2.2.SCH
DRAWING TITLE 08_E076 MJT 07/04/08 Removed 4-off handbag links (ITEM300, 400, 500, 700) 2.2
A28/P28 - Top Level Sheet 08_E069 MJT 25/03/08 Added rubber damping pads on top of components. 2.1
Filename: L991CT1_2.2.SCH 07_E226 PK 28/11/07 Correct O ring quantity 2.0
23425 Notes: 07_E156 SLRR 12/09/2007 None to this sheet 1.0
A & R Cambridge Ltd. A28 07_E068 PK 20/04/2007 Output devices replaced, seperate emitter resistors added B.0
Pembroke Avenue ECO No. INITIALS DATE DESCRIPTION OF CHANGE ISSUE
Waterbeach
Cambridge CB5 9PB Contact Engineer: Andrew Dutton Contact Tel: (01223) 203 200 Printed: 25-Apr-2008 Sheet 1 of 8 DRAWING NO. L991C1
ITEM203 1 F006 Clip For SW Profile Heatsink
MAINS WIRING AND AUXILIARY SUPPLY
NEUTRAL ANNOTATION
9VRMS
TX200
1 5 D214
SH200 BAS16
EMC Shield NF SOT-323
SKT200 115V
C200 9V
+4.8V(D)
2A
2B
2
N 3N3 REG201 +4.8V(D)
250V 2 6 LM317T
E CER EARTH C209
220N 115V 230V
3 7
FS202 +4.8V(D) RLY200C
R218 D215
ADJ
L C201 275V Omron
FS200 T500mA 220R BAS16
3N3 PP X2 G2R-24-5VDC
1
1A
1B
T2.5A R452 0W25 SOT-323
250V C221 TO-220
S506 115V 9V MF
BULGIN CER 100N HS201A
PX0580 SW200 100V SW50-2
1 FS201 FHLDR200 DBR203 R219 C226
18-000-0019 4 8 MKS2 8.8C/W
T2.5A 20mm HLDR 3BDF01M 22R 1000UF
S506 PCB Mount Frame C225 0W125 10V
7A9311 0805 YK R216 P202 TR202
1000UF
This EMC can should now not appear FHLDR201 25V PWR_ON FMMT497
on any BoM as there is a safety 20mm HLDR YK R217 2K2 SOT-23
LIVE 680R
issue regarding the can shorting to a 0W125
live mains track on the top layer. 0W125 0805
RLY200A 0805
Omron 0V(D)
Consider removing the holes for the G2R-24-5VDC 0V(D)
can or perhaps move mains track◦ Jabse Service Manual Search 2024 ◦ Jabse Pravopis ◦ onTap.bg ◦ Other service manual resources online : Fixya ◦ eServiceinfo