Arcam-A32-int-sm维修电路图 手册.pdf

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1、A32 FMJ A32, P35 & P35/3 Amplifi ers Service Manual ARCAMARCAM Issue 1.0 RadioFans.CN Contents List ! Phono board L870 oCircuit description oComponent overlay oParts list oCircuit diagrams ! Amplifier & PSU board L882 oCircuit description oComponent overlay oParts list oCircuit diagrams ! Display bo

2、ard L928 oComponent overlay oParts list oCircuit diagrams ! Preamplifier board L937 oCircuit description oComponent overlay oParts list oCircuit diagrams ! 3rd Channel Amplifier board L911 oComponent overlay oParts list oCircuit diagrams ! Transformer specifications oL914TX oL915TX ! General assembl

3、y oA32 - Mechanical parts list oP35 - Mechanical parts list oP35/3 - Mechanical parts list RadioFans.CN Phono Board L870 Contents ! Circuit description ! Component overlay ! Parts list ! Circuit diagrams RadioFans.CN AV8 Phono Board Circuit Description Refer to circuit diagram L870 sheet 1 The phono

4、 board is a simple single stage RIAA amplifier and consists of two channels of high gain amplification, and the ability to switch between moving magnet (MM) and moving coil (MC) settings. PSU The unit derives its + 15V regulated rails from the unit it is fitted into with only local decoupling capaci

5、tors on board. Interface The unit connects to the host unit via a 8 way connector. Amplification The left channel has designators beginning with 100, and the right with 200. For the purposes of this description the left channel will be described, as the right channel is the same in all respects. The

6、 amplifier is a small signal class A voltage feedback amplifier with switch able gain. The input consists of an actively loaded differential pair of very low noise PNP transistors (TR106, TR107). These transistors are very specific and should only be replaced with identical parts with the E grade hi

7、gh gain. TR100 and TR101 form a current source for the pair, which sets the quiescent current for the entire amplifier. The active load consists of TR110 and TR111, which forms part of the differential current mirror with TR112, TR113 & TR114. This differential stage also has an active load (TR102 &

8、 TR103) to keep gain to a maximum. Both of these differential stages are designed to have as much gain as possible to enable the single stage design. The RIAA response is achieved in the feedback network: C101, C110, C111, C112, C119, C120 and R115, R112. C115 is used to correct between MM and MC ga

9、ins as the amplifier is non-inverting. SW100 switches between MM and MC. Two poles of the switch change between the different loading required for each type of the cartridge: R108 & C109 for MM and added in parallel for MC R104 & C108. The other two poles change the feedback resister value to alter

10、the gain: R105 for MM and added in parallel for MC R123. The DC offset is controlled by a non-inverting servo built around IC100. The amount of servo current is different for each gain setting via R111 (MM) and R124 (MC) so that the low frequency high pass point remains the same for both settings. H

11、owever the high pass point for the circuit is set by C113. This gives a warp filter, stops DC start-up thumps from upsetting DC coupled circuitry and an approximation of the RIAA/IEC curve (-2dB 20Hz) The output is class A buffered by a dual mirror follower (TR104, TR105, TR108, TR109). The quiescen

12、t current is set by D100 and R118 and R119. Closed loop stability is achieved with C16, C117, giving symmetrical slewing capability. RadioFans.CN RadioFans.CN L870 Phono Board Parts List Issue 2.0 Designator Part Description C12A410CERD 100N 63V -20% +80% RA C1002N622ELST 22U 63V C1012D210PPRO 1N0 5

13、% 63V RA C1022P710ASELEC 100U 25V SILMIC C1032P710ASELEC 100U 25V SILMIC C1042K410PEST 100N 63V 10% C1052K410PEST 100N 63V 10% C1062K410PEST 100N 63V 10% C1072K410PEST 100N 63V 10% C1082D147WPPRO W 470P 63V 5% RA C1092D110WPPRO W 100P 63V 5% RA C1102D247NPPRO 4N7 63V 5% RA C1112D310PPRO 10N 63V 1% A

14、XIAL C1122D310PPRO 10N 63V 1% AXIAL C1132K510CAP MKS2 1U0 16V 10% C1152D213NPPRO 1N3 63V 5% RA C1162D147WPPRO W 470P 63V 5% RA C1172D147WPPRO W 470P 63V 5% RA C1182U610ELST NON POLAR 10UF 35V C1192D110NPPRO 100P 63V 5% RA C1202D210PPRO 1N0 5% 63V RA C2002N622ELST 22U 63V C2012D210PPRO 1N0 5% 63V RA

15、C2022P710ASELEC 100U 25V SILMIC C2032P710ASELEC 100U 25V SILMIC C2042K410PEST 100N 63V 10% C2052K410PEST 100N 63V 10% C2062K410PEST 100N 63V 10% C2072K410PEST 100N 63V 10% C2082D147WPPRO W 470P 63V 5% RA C2092D110WPPRO W 100P 63V 5% RA C2102D247NPPRO 4N7 63V 5% RA C2112D310PPRO 10N 63V 1% AXIAL C212

16、2D310PPRO 10N 63V 1% AXIAL C2132K510CAP MKS2 1U0 16V 10% C2152D213NPPRO 1N3 63V 5% RA C2162D147WPPRO W 470P 63V 5% RA C2172D147WPPRO W 470P 63V 5% RA C2182U610ELST NON POLAR 10UF 35V C2192D110NPPRO 100P 63V 5% RA C2202D210PPRO 1N0 5% 63V RA D1003A4148SSDIODE 1N4148 75V D1013A4148SSDIODE 1N4148 75V D

17、1023A4148SSDIODE 1N4148 75V D2003A4148SSDIODE 1N4148 75V D2013A4148SSDIODE 1N4148 75V D2023A4148SSDIODE 1N4148 75V IC1005B071IC FET OPAMP TL071 IC2005B071IC FET OPAMP TL071 PCB1L870PB_2PRINTED CIRCUIT BOARD R1001H133RES MF W4 1% 330R R1011H110RES MF W4 1% 100R R1021H110RES MF W4 1% 100R R1041H110RES

18、 MF W4 1% 100R R1051H110RES MF W4 1% 100R R1061H110RES MF W4 1% 100R R1081H347RES MF W4 1% 47K R1091H312RES MF W4 1% 12K R1101H312RES MF W4 1% 12K R1111H356RES MF W4 1% 56K R1121H410RES MF W4 1% 100K R1131H410RES MF W4 1% 100K R1141H410RES MF W4 1% 100K R1151H315RES MF W4 1% 15K R1161H522RES MF W4 1

19、% 2M2 RadioFans.CN L870 Phono Board Parts List Issue 2.0 Designator Part Description R1171H522RES MF W4 1% 2M2 R1181H022RES MF W4 1% 22R R1191H022RES MF W4 1% 22R R1201H022RES MF W4 1% 22R R1211H022RES MF W4 1% 22R R1221H339RES MF W4 1% 39K R1231H010RES MF W4 1% 10R R1241H256RES MF W4 1% 5K6 R2001H1

20、33RES MF W4 1% 330R R2011H110RES MF W4 1% 100R R2021H110RES MF W4 1% 100R R2041H110RES MF W4 1% 100R R2051H110RES MF W4 1% 100R R2061H110RES MF W4 1% 100R R2081H347RES MF W4 1% 47K R2091H312RES MF W4 1% 12K R2101H312RES MF W4 1% 12K R2111H356RES MF W4 1% 56K R2121H410RES MF W4 1% 100K R2131H410RES M

21、F W4 1% 100K R2141H410RES MF W4 1% 100K R2151H315RES MF W4 1% 15K R2161H522RES MF W4 1% 2M2 R2171H522RES MF W4 1% 2M2 R2181H022RES MF W4 1% 22R R2191H022RES MF W4 1% 22R R2201H022RES MF W4 1% 22R R2211H022RES MF W4 1% 22R R2221H339RES MF W4 1% 39K R2231H010RES MF W4 1% 10R R2241H256RES MF W4 1% 5K6

22、SK18D230PHONO SKT 2-WAY HOR EMC GOLD SK28K24088-WAY AMP CT CONN SW100A1013SW PUSH 4PCO TR1004A556TRANS LF SS P BC556B TR1014A556TRANS LF SS P BC556B TR1024A556TRANS LF SS P BC556B TR1034A556TRANS LF SS P BC556B TR1044A556TRANS LF SS P BC556B TR1054A556TRANS LF SS P BC556B TR1064A1085TRANS LF SS P 2S

23、A1085 TR1074A1085TRANS LF SS P 2SA1085 TR1084A546TRANS LF SS N BC546B TR1094A546TRANS LF SS N BC546B TR1104A546TRANS LF SS N BC546B TR1114A546TRANS LF SS N BC546B TR1124A546TRANS LF SS N BC546B TR1134A546TRANS LF SS N BC546B TR1144A546TRANS LF SS N BC546B TR2004A556TRANS LF SS P BC556B TR2014A556TRA

24、NS LF SS P BC556B TR2024A556TRANS LF SS P BC556B TR2034A556TRANS LF SS P BC556B TR2044A556TRANS LF SS P BC556B TR2054A556TRANS LF SS P BC556B TR2064A1085TRANS LF SS P 2SA1085 TR2074A1085TRANS LF SS P 2SA1085 TR2084A546TRANS LF SS N BC546B TR2094A546TRANS LF SS N BC546B TR2104A546TRANS LF SS N BC546B

25、 TR2114A546TRANS LF SS N BC546B TR2124A546TRANS LF SS N BC546B TR2134A546TRANS LF SS N BC546B TR2144A546TRANS LF SS N BC546B RadioFans.CN 12345678 A B C D 87654321 D C B A ISSUE DRAWING NO. 23425 DRAWING TITLE Drawn by: DATE Filename ECO No.DESCRIPTION OF CHANGE G:DATAECOECO AGENDA01_1070 l870 A85 P

26、HONO ISSUE2L870_2.0.ddb - L870c1_2.0.PRJ A & R Cambridge Ltd. Pembroke Avenue Denny Industrial Centre Waterbeach Cambridge CB5 9PB A85 PHONO STAGE - TOP LEVEL Circuit Diagram L870C1 JBR23-Apr-2001 INITIALS Date Printed 13Sheetof Notes: 1 EMC SK1 PHONO2HG 0V_SIG 0V_SIG LEFT INLEFT OUT LEFT CHANNEL L8

27、70C2_2.0.SCH RIGHT INRIGHT OUT RIGHT CHANNEL L870C3_2.0.SCH 1 2 3 4 5 6 7 8 SK2 AMPCT8 +15V -15V 0V_HF0V_SIG Q_1 Q_2 Q_3 Q_4 Q_5 Q_6 Q_7Q_8 PCB PCB1 L870PB_2 Update Box EL1 UPDATE_BOX C1 100N CD 00_1051JAG22/3/01PRODUCTION ISSUE1 01_1070JAG17/4/01updated pcb and scm2 RadioFans.CN 12345678 A B C D 87

28、654321 D C B A ISSUE DRAWING NO. 23425 DRAWING TITLE Drawn by: DATE Filename ECO No.DESCRIPTION OF CHANGE G:DATAECOECO AGENDA01_1070 l870 A85 PHONO ISSUE2L870_2.0.ddb - L870C2_2.0.SCH A & R Cambridge Ltd. Pembroke Avenue Denny Industrial Centre Waterbeach Cambridge CB5 9PB A85 PHONO STAGE - LEFT CHA

29、NNEL Circuit Diagram L870C2 JBR23-Apr-2001 INITIALS Date Printed 23Sheetof Notes: TR106 2SA1085 TR107 2SA1085 R120 22R MF R121 22R MF R105 100R MF R108 47K MF R101 100R MF R102 100R MF + C102 100U SILMIC + C103 100U SILMIC R100 330R MF +C100 22U EL R109 12K MF R110 12K MF C105 100N PE R117 2M2 MF R1

30、11 56K MF R113 100K MF R114 100K MF TR111 BC546B TR110 BC546B TR114 BC546B TR112 BC546B TR113 BC546B TR100 BC556B TR101 BC556B TR102 BC556B TR103 BC556B TR104 BC556B TR105 BC556B TR108 BC546B TR109 BC546B +15V -15V R122 39K MF R112 100K MF R115 15K MF 4 5 6 SW100B 4PCO 10 11 12 SW100D 4PCO R104 100R

31、 MF C108 470P PPW R123 10R MF C104 100N PE C107 100N PE R116 2M2 MF 3 2 6 74 IC100 TL071CD 0V_SIG0V_SIG D100 1N4148 R118 22R MF R119 22R MF C106 100N PE 0V_SIG0V_HF 0V_SIG 0V_SIG0V_HF D101 1N4148 D102 1N4148 R106 100R MF LEFT IN LEFT OUT Q_101 Q_102 Q_103 C109 100P PPW R124 5K6 MF C117 470P PPW C116

32、 470P PPW C111 10N PP AX C112 10N PP AX C118 10U NP C113 1U0 PE C115 1N3 PP C110 4N7 PP C101 1N0 PP C119 100P PP 00_1051JAG22/3/01PRODUCTION ISSUE1 C120 1N0 PP 01_1070JAG17/4/01updated pcb and scm2 RadioFans.CN 12345678 A B C D 87654321 D C B A ISSUE DRAWING NO. 23425 DRAWING TITLE Drawn by: DATE Fi

33、lename ECO No.DESCRIPTION OF CHANGE G:DATAECOECO AGENDA01_1070 l870 A85 PHONO ISSUE2L870_2.0.ddb - L870C3_2.0.SCH A & R Cambridge Ltd. Pembroke Avenue Denny Industrial Centre Waterbeach Cambridge CB5 9PB A85 PHONO STAGE - RIGHT CHANNEL Circuit Diagram L870C3 JBR23-Apr-2001 INITIALS Date Printed 33Sh

34、eetof Notes: TR206 2SA1085 TR207 2SA1085 R220 22R MF R221 22R MF R205 100R MF R208 47K MF R201 100R MF R202 100R MF + C202 100U SILMIC + C203 100U SILMIC C209 100P PPW R200 330R MF +C200 22U EL R209 12K MF R210 12K MF C205 100N PE R217 2M2 MF R211 56K MF R213 100K MF R214 100K MF TR211 BC546B TR210

35、BC546B TR214 BC546B TR212 BC546B TR213 BC546B TR200 BC556B TR201 BC556B TR202 BC556B TR203 BC556B TR204 BC556B TR205 BC556B TR208 BC546B TR209 BC546B +15V -15V R222 39K MF R212 100K MF R215 15K MF 1 2 3 SW100A 4PCO 7 8 9 SW100C 4PCO R204 100R MF C208 470P PPW R223 10R MF C204 100N PE C207 100N PE R2

36、16 2M2 MF 3 2 6 74 IC200 TL071CD 0V_SIG0V_SIG D200 1N4148 R218 22R MF R219 22R MF C206 100N PE 0V_SIG0V_HF 0V_SIG 0V_SIG0V_HF D201 1N4148 D202 1N4148 R206 100R MF RIGHT IN RIGHT OUT Q_201 Q_202 Q_203 R224 5K6 MF C217 470P PPWC216 470P PPW C215 1N3 PP C211 10N PP AX C212 10N PP AX C218 10U NP C213 1U

37、0 PE C219 100P PP C210 4N7 PP C201 1N0 PP 00_1051JAG22/3/01PRODUCTION ISSUE1 C220 1N0 PP 01_1070JAG17/4/01updated pcb and scm2 RadioFans.CN Amplifier + PSU Board L882 Contents ! Circuit description ! Component overlay ! Parts list ! Circuit diagrams RadioFans.CN Amplifier & PSU Circuit Description R

38、efer to L882 circuit diagrams This is the printed circuit board that provides the power supply and output stage amplifiers for the A32 integrated and P35 power amplifiers. Its function is to: ! Drive the loudspeakers ! Provide an (always on) auxiliary 5VDC supply for the micro controller and display

39、 interface ! Receive logic signals from the micro controller to turn on the main amplifier supply relay (mains) and connect either pair of speaker output sockets ! Send logic signals to the micro controller pertaining to the state of the amplifiers (short circuit protection, DC offset protection, th

40、ermal protection) ! Receive and demodulate RC5 remote style control codes via the rear panel jack and transmit them to the micro controller ! Send a 12V trigger output via the rear panel jack for control of an auxiliary power amp when the unit is on ! Receive a 12V trigger input from the rear jack (

41、for use in the power amp only version) ! Drive a pair of headphones via attenuating resistor networks The power amplifier is a symmetrical, class B, bipolar junction transistor output, current-feedback design (of which more later) with DC-coupled signal and feedback paths, featuring an active integr

42、ating voltage servo to control DC offsets. It features instantaneous safe operating area protection in addition to sending a signal to the micro to turn off the output relays in the event of user or thermal overload. Since it is a DC-coupled design, the unit senses DC at the output and triggers the

43、micro to turn off the loudspeaker relays in the event of excessive levels (possibly due to a faulty source component or short circuit output transistor). The output stage uses Sanken specialised audio amplifier power bipolar Darlington transistors which are optimised for use with this type of topolo

44、gy. Consequently the unit has excellent measured performance in terms of noise, slew rate, output impedance and distortion (harmonic and intermodulated) and is essentially load invariant (to a first order the measured performance is independent of the load impedance). L882 Circuit Sheet 1 The audio

45、input to the amplifier is connected to SK102 (which connects to the output of the preamp PCB). This signal is passed on via SK104A which forms the preamp out connection to the outside world. SK104B provides the power amp input connection, with switchSW100 selecting between pre / power and integrated

46、 modes. The unit is wired as a preamp / power amp combination with the switch depressed, allowing the user to insert a processor or other function (e.g. graphic EQ) between the output of the preamp and the input of the power amp. With the switch in the out position the power amp input socket is igno

47、red and the input to the power amp is connected internally to the output of the preamp. PL100 and PL101 are handbag links fitted to the power amp only version to connect both pairs of phono sockets in parallel for daisy chaining (as there is no preamp output on a power amp). Relays RLY100 and RLY101

48、 switch the two pairs of loudspeaker output sockets and are controlled by the micro lines describes above. Transistors TR100 and TR101 operate in constant current sink mode which allow relay current to be approximately constant although the main power supply rails will vary with mains input and load

49、 conditions. The current is around 20mA per relay. Star point SP100 is the ground mecca for the entire amplifier (comprising all three PCBs within the unit). All of the separately named grounds are joined explicitly at this point. Different named grounds are used to ensure that no two different grounds share copper, which could compromise the noise, distortion or crosstalk performance of the amplifier. The loudspeaker output signal