background image

23

120V Tone/Volume Control PCB

Resistors

Capacitors

Reference

Designator

Description

Part Number

See  Note

R2, 3, 4, 5, 7, 26,
27, 28, 30

1.2K

, 5%, 1/4W,

CF

185393

R6

47K

, 5%, 1/4W,

CF

185316

R8, 39

100

, 5%, 1/4W

CF

185429

R9, 10, 13, 16

1.0K

, 5%, 1/4W,

CF

185442

R11, 40

1OK

, 5%, 1/4W,

CF

185433

R12

51

, 5%, 1/4W,

CF

185398

R14, 15, 41, 42,
43

VARISTOR-TVS
14V

185399

R17, 18

100K

, 5%, 1/4W,

CF

185427

R19

3.3K

, 5%, 1/4W,

CF

185401

R20, 21, 34

20K

, 5%, 1/4W,

CF

185402

R22

POT, 5K

, PCB,

MTG

185403

R23

8.2K

, 5%, 1/4W,

CF

185404

R24, 37

5.1K

, 5%, 1/4W,

CF

185326

R29, 31

POT, 100K

,

PCB, MTG

185406

R32, 33

150K

, 5%, 1/4W  

185407

R35

75K

, 5%, 1/4W  

185408

R36

91K

, 5%, 1/4W  

185409

R38

75

, 5%, 1/4W,

CF

185410

Reference

Designator

Description

Part Number

See  Note

C1

30 PF, 1KV, CER,
10%

185345

C2, 3, 11, 12

47 

µ

F, 25V,

ELECT RDL

185417

C4, 5

100 

µ

F, 25V,

ELCT RDL

185419

Summary of Contents for FREESPACE BMA-125

Page 1: ...l PCB Part List 23 24 120V Equalizer PCB Part List 25 26 230V Main Assembly Part list 27 28 230V Amp PCB Part List 29 31 230V Tone Volume Equalizer PCB Part List 32 35 Input Module 2B37 Part List 36 I...

Page 2: ...water pipe conduit etc to all exposed metal parts of the unit antennas handle bracket metal cabinet screw heads metallic overlays control shafts etc especially any exposed metal parts that offer an e...

Page 3: ...traps that connect to conductive floor mats Avoid touching the leads or contacts of ESDS devices or PC boards even if properly grounded Handle boards by the edges only Transport or store ESDS devices...

Page 4: ...nsformer 31 65V 8 transformer 22 35V 4 direct Functional Outputs EQ Out 1 0V into 600 post master volume Line Out 1 0V into 600 post master volume Tape Out 650mV into 10K pre master volume Mixer Outpu...

Page 5: ...to 140 F 10 C to 60 C Output Protection Electronic foldback and thermal overload both self restoring DC offset detection for direct coupled output Size 17 W x 12 75 D x 4 5 H 43 2 X 32 4 x 11 4 cm des...

Page 6: ...output EQ bypassed EIA SE101A Direct Transformer 20Hz 20KHz 1dB 20Hz 20KHz 1dB 2dB Power Bandwidth at rated output THD EQ bypassed Direct Transformer 20Hz 20KHz 1dB 1 THD 50Hz 20KHz 1dB 2dB 1 THD S N...

Page 7: ...to the chassis 5 2 Remove the input Five bass and treble control knobs by pulling straight away on them 5 3 Remove the three nuts that secure the input Five bass and treble controls to the chassis 5...

Page 8: ...lizer PCB Removal 11 1 Remove the connector from the equalizer PCB 13 3 Remove the four screws and nuts that secure the transformer bracket to the transformer 14 Speaker Output Transformer Replace men...

Page 9: ...4 Replace the wires that connect to the AC outlet power switch and driver PCB 17 Output Transistor and Heat sink Removal 18 1 Remove the four screws that secure the heat sink to the chassis 18 2 Lift...

Page 10: ...s by pulling them straight away from the unit 5 2 Remove the three nuts that secure the input five bass and treble controls to the chassis 5 3 Remove the two nuts that secure the PCB shield to the cha...

Page 11: ...ker output terminals 11 2 Remove the four screws that secure the transformer to the chassis 12 Speaker Output Transformer Replace ment 12 1 Lower the transformer into the chas sis so that the wires fa...

Page 12: ...lace if necessary Make sure the transistor and the transistor socket is flush with the heat sink 16 2 Replace the two screws that secure the transistor to the heat sink 16 3 Lower the heat sink into t...

Page 13: ...treble control to the full counter clockwise position Measure the output It should be 3 5 dB 1 dB 1 7 Rotate the treble control to the full clockwise position Measure the output It should be 3 2 dB 1...

Page 14: ...uency Output dB Tolerence dB 50Hz 0 2 1KHz ref 20KHz 0 2 5 4 5 Adjust Input Five until 8 875 Vrms is measured across the 8 load Reference a dB meter to the output 4 6 Measure the response according to...

Page 15: ...he applied signal 11 3 Measure the Line Output It should be 67 dB 1 dB 11 4 Reference a dB meter to the Line Output 11 5 Change the input signal to 20Hz With the Mic EQ switch in the FLAT setting meas...

Page 16: ...9 1 5 1KHz ref 5KHz 5 8 1 5 12 5KHz 12 4 85 2 15 20KHz 2 1 3 14 4 Move the EQ selector switch to the Model 32 position Measure the response according to the following table 230V Variation Tests Note P...

Page 17: ...ger is required before ordering 2 The individual parts located on the PCB are listed in the electrical part list 3 This part is critical for safety purposes Failure to use a substitute replacement wit...

Page 18: ...220 F 100V 20 185241 1 Cap 3300 Pf 1400V CER 185242 1 3 F101 Fuse 4A 250V SLO BLO 185245 1 3 S101 Power Switch 185271 1 3 Power Cord 185233 1 Bracket Heatsink Mtg 185234 4 Bracket Transformer 185235...

Page 19: ...RMER T102 AUDIO TONE VOLUME PCB DRIVER PCB INPUT MODULE INPUT MODULE C101 Q101 103 Q102 104 S101 POWER R100 MASTER TREBLE BASS INPUT 5 INPUT 4 INPUT 3 INPUT 2 INPUT 1 R27 R22 R7 R104 R103 R102 R101 F1...

Page 20: ...1 R10 11 10 5 1 4W CF 185322 R12 2 4K 5 1 4W CF 185323 R13 6 8K 5 1 4W CF 185324 R14 180K 5 1 4W CF 185325 R15 40 5 1K 5 1 4W CF 185326 R16 1 5 5 1 4W CF 185327 R17 150 5 1 4W CF 185328 R18 21 22 26 2...

Page 21: ...cription Part Number See Note C2 11 4 7 UF 50V ELCT NP 185342 C3 4 470 PF 500V CER 10 185343 C5 10 PF 1KV CER 10 185344 C6 30 PF 1KV CER 10 185345 C7 8 220 UF 50V ELCT RDL 185346 C9 1 UF 200V MYLAR 18...

Page 22: ...cription Part Number See Note Q1 2 3 5 13 15 2N5210 185365 Q4 MPS A93 185366 Q6 MPSU06 185367 Q7 MJE253 185368 Q8 2N5088 185369 Q9 2N5086 185370 Q10 MPSU56 185371 Q11 MJE243 185372 Q12 MPS6566 185373...

Page 23: ...398 R14 15 41 42 43 VARISTOR TVS 14V 185399 R17 18 100K 5 1 4W CF 185427 R19 3 3K 5 1 4W CF 185401 R20 21 34 20K 5 1 4W CF 185402 R22 POT 5K PCB MTG 185403 R23 8 2K 5 1 4W CF 185404 R24 37 5 1K 5 1 4W...

Page 24: ...20 185414 C16 22 PF 1KV CER 10 185415 C17 18 19 20 01 F 50V CER 20 185416 C21 22 33 F 25V ELCT RDL 185418 Reference Designator Description Part Number See Note Q1 2N5088 185369 Q2 VN0300M 185423 Refe...

Page 25: ...29 30 47K 1 4W 5 CF 185316 R31 32 475 1 4W 1 185484 R33 AT C13 100 5 1 4W CF 185429 Reference Designator Description Part Number Reference C1 27 10 UF 25V ELECT RDL 185501 C2 3 10 11 0056 UF 5 185378...

Page 26: ...26 Reference Designator Description Part Number Reference J1 12 PIN FRICTION LOW 185361 JU1 WIRE SOL BARE TND 22 A 185391 U1 4 SOCKET 8 PIN 185392 120V Equalizer PCB Miscellaneous...

Page 27: ...103 106 109 112 115 1 F 50V Cer 185290 9 SW101 Power Switch 185293 1 3 SW102 Slide SPDT 185294 1 TS101 Rcpt Spkr 185296 1 TS102 Terminal Barrier 185297 1 TS103 Terminal Strip 6 Cont 185298 1 TS104 Ph...

Page 28: ...Cord EUR 185314 1 3 Power Cord U K 185283 1 3 Power Cord AUS 185286 1 3 2B50 Dual input module Mic screws Stereo summing input AUX 180139 2B50 2 2B37 Dual input module Mic Screws Stereo summing input...

Page 29: ...F 185430 R7 2 7K 5 1 4W CF 185431 R8 12K 5 1 4W CF 185432 R9 10 11 37 46 10K 5 1 4W CF 185433 R12 15 620 5 1 4W CF 185434 R13 16 390 5 1 4W CF 185435 R14 17 62K 5 1 4W CF 185436 R22 23 43K 5 1 4W CF 1...

Page 30: ...5472 Q12 13 2N5210 185473 Reference Designator Description Part Number See Note U1 LM833 185474 U2 7815 185475 U3 7915 185476 Reference Designator Description Part Number See Note CR1 2 5 7 17 21 28 3...

Page 31: ...185483 3 J1 4 PIN FRICTION LOCK 185484 J2 MOLEX 6 PIN 185485 J3 MOLEX 5 PIN 185486 U2 3 HEATSINK W LEGS 185487 Q5 Q6 BRKT HTSNK 185488 Q5 Q6 U2 U3 LK WASH 4 SPLT SPRING 185489 Q5 Q6 U2 U3 NUT 4 4 HEX...

Page 32: ...9 39 5 1 4W CF 185500 R21 44 55 100K 5 1 4W CF 185427 R22 27 POT 100K PCB MTG 185502 R23 25 150K 5 1 4W CF 185503 R24 20K 5 1 4W CF 185504 R26 75K 5 1 4W CF 185505 R28 91K 5 1 4W CF 185506 R29 34 R56...

Page 33: ...te C1 4 26 4 7 F 50V ELCT NP 185521 C2 21 220 PF 50V CER 20 185463 C3 5 6 41 47 F 25V ELCT RDL 185523 C7 43 46 47 01 F 50V CER 20 185455 C8 470 PF 50V CER 20 185461 C9 56 PF 50V CER 20 185526 C10 11 1...

Page 34: ...3 Reference Designator Description Part Number See Note Q1 2N5086 185470 Q3 2N3904 185543 Reference Designator Description Part Number See Note U1 2 4 5 LM833 185474 U6 DG211CJ 185545 Reference Design...

Page 35: ...185548 JU1 3 PIN 1 RT ANG PC 185549 J2 9 PIN 185550 J3 FRICTION LK 185551 J4 6 PIN FRICTION LK 185552 J5 8 PIN 185553 J6 FRICTION LK 185484 J7 3 PIN FRICTION LK 185555 U1 2 4 5 SOCKET 8 PIN IC PCB 18...

Page 36: ...ence Designator Description Part Number See Note C1 2 10 11 01 F 50V CER 185416 C3 12 100pF 50V CER 185453 C4 33 F 25V Elect 185418 C13 16 47 F 25V Elect 185417 C17 18 68 F 50V Elect 185338s Reference...

Page 37: ...4W 5 185426 Reference Designator Description Part Number See Note C1 1200 PF CER 50V 185574 C2 5 8 10 01 UF CER 25V 185455 C6 7 10 UF ELCT RDL 25V 185575 C11 12 47 UF ELCT RDL 25V 185573 C13 20 1 UF...

Page 38: ...8 Reference Designator Description Part Number See Note J1 3 PIN 185555 JU1 2 PIN 185558 J2 5 PIN 185551 J3 4 RCA 185301 U1 2 IC SOCKET 8 PIN 185556 Input Module 2B50 Part List continued Miscellaneous...

Page 39: ...Figure 2 2B37 Schematic and PCB Layout 39...

Page 40: ...Figure 3 2B50 Schematic and PCB Layout 40...

Page 41: ...Figure 4 120V Driver PCB Layout Figure 5 120V Tone Volume Control PCB Layout 41...

Page 42: ...Figure 6 120V Equalizer PCB Layout Solder Side Figure 7 120V Equalizer PCB Layout Component Side 42...

Page 43: ...Figure 8 230V Driver PCB Layout 43...

Page 44: ...Figure 9 230V Tone Volume Equalizer PCB Layout 44...

Page 45: ...Figure 10 230V Wiring Diagram Part 1 45...

Page 46: ...Figure 11 230V Wiring Diagram Part 2 46...

Page 47: ...47...

Page 48: ...IFICATIONS AND FEATURES SUBJECT TO CHANGE WITHOUT NOTICE BOSE CORPORATION THE MOUNTAIN FRAMINGHAM MASSACHUSETTS USA 01701 P N 177864 3 96 REV 0 FOR TECHNICAL ASSISTANCE OR PART ORDERS CALL 1 800 367 4...

Page 49: ...FREESPACE BUSINESS MUSIC AMPLIFIER BMA 125 120 230V Service Manual Part Number 177864 1996 Bose Corporation 120V Version shown...

Reviews: