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QSC RMX 1450 Technical & Service Manual

Other manuals for RMX 1450: User Manual, Specifications, Service Bulletin
Manual is about: RMX Series

Summary of RMX 1450

  • Page 1

    Technical ser vice manual rmx™ series ▲ ▲ ▲ ▲ ▲ rmx 850 ▲ ▲ ▲ ▲ ▲ rmx 1450 ▲ ▲ ▲ ▲ ▲ rmx 2450 *td-000098-00* td-000098-00 rev. B.

  • Page 3: Rmx 850

    Rmx series technical service manual 1 qsc audio products, inc. Technical services group phone: 1-800 qsc audio (1-800-772-2834) usa only +1 (714) 957-7150 fax: +1 (714) 754-6173 postal: 1665 macarthur blvd. Costa mesa, california 92626 usa e-mail: tech_support@qscaudio.Com web: http://www.Qscaudio.C...

  • Page 4

    2 qsc audio products, inc. Rmx 850 rmx 1450 rmx 2450 output power in watts ftc: 20 hz–20 khz @ 0.1% thd, both channels driven 8 Ω per channel 185 260 450 4 Ω per channel 280 400 650 eia: 1 khz @ 0.1% thd, both channels driven 8 Ω per channel 200 280 500 4 Ω per channel 300 450 750 1 khz @ 1% thd, ty...

  • Page 5: Table of Contents

    Rmx series technical service manual 3 table of contents rmx series performance specifications ........................................................................................................................................ 4 1. Introduction ......................................................

  • Page 6: 1. Introduction

    4 qsc audio products, inc. Solder braid 1. Introduction 1.1 service bulletins contact qsc technical services to make sure you have the most up-to-date service bulletins for rmx series amplifiers. Service bulletins may be distributed in hard copy, via fax, and electronically (adobe acrobat pdf) via c...

  • Page 7

    Rmx series technical service manual 5 solder solder tweezers solder insertion 1 with a soldering iron and 60/40 or 63/37 eutectic-type solder, melt just enough solder onto one pad to create a small mound (figure 1.3). 2 grasp the component in the middle with tweezers. Melt the small mound of solder ...

  • Page 8: 1.4 Series Description

    6 qsc audio products, inc. 1.4 series description qsc’s rmx series amplifiers are entry-level professional audio products, designed for good, basic performance and reliability at low price. The series comprises three models: the rmx 850, rmx 1450, and rmx 2450. Each one has two audio channels and is...

  • Page 9

    Rmx series technical service manual 7 the transistor pair to keep crossover distortion minimal. In parallel with the trimpot is a 50-ohm thermistor with a negative temperature coefficient; as the circuitry warms, its resistance decreases. This reduces v be on both q105 and q106, decreasing the bias ...

  • Page 10

    8 qsc audio products, inc. Bridged mono operation and protection when the amplifier is operated in bridged mono, its two channels work in tandem to produce up to twice the voltage swing that a single channel is capable of. To do this, channel 2 produces a signal identical to channel 1’s, but opposit...

  • Page 11

    Rmx series technical service manual 9 b c e 1 2 3 b e c b c e toshiba g d s b c e 2n3904 (npn) and 2n3906 (pnp) small-signal transistors mje15032 (npn) and mje15033 (pnp) driver transistors irfz44 tmos power field effect transistor 2sc5200 (pnp) and 2sa1943 (npn) power transistors mac224 triac mt1 m...

  • Page 12: 3.1 Excessive Current Draw

    10 qsc audio products, inc. When first checking the operation of an amplifier on the bench, always turn your variable transformer down to zero before plugging the amplifier in. After you turn the amplifier on, gradually turn up the ac voltage as you observe the amplifier’s behavior and its current d...

  • Page 13: 3.4 Instability

    Rmx series technical service manual 11 fan doesn’t run • the fan is defective. • check the fan connection to the ac board. • check r1 and br1 on the ac board. Fan runs always on high speed • q3 and/or u2 are shorted. • check ptc thermistors r4 and r7. 3.3 faults with signal present the customer comp...

  • Page 14: Problems

    12 qsc audio products, inc. 3.5 power supply & rail balancing problems symptoms covered: • insufficient or excessive current limiting into a shorted load • op amp rails too high with a shorted load • uneven voltages on supply rails a channel’s output current should remain unaffected when driving res...

  • Page 15: Current Limits

    Rmx series technical service manual 13 bias, you will need to shut the amplifier off and let it cool down before you resume. Tools and resources you will need: • small flat screwdriver (non-conductive) for adjusting trimpots • dc voltmeter • ac power procedure 1. Turn the amplifier’s gain controls a...

  • Page 16: 5. Servicing Rmx Amplifiers

    14 qsc audio products, inc. 5. Servicing rmx amplifiers 5.1 mechanical disassembly and re-assembly replacing components will usually require removing the channel modules and/or ac board from the amplifier chassis, especially on the rmx 850 and rmx 1450, which have single-side printed circuit boards....

  • Page 17: 6. Replacement Parts

    Rmx series technical service manual 15 6. Replacement parts 6.1 rmx 850 replacement parts qsc part # description qty. Notes or component reference misc. 1806-2505-0 power transformer 700 1 2113-1144-0 ac inlet 1 2444-1001-1 knob control 2 4134-8432-0 rack-mount bracket 2 5200-4717-0 rocker power swi...

  • Page 18

    16 qsc audio products, inc. 4860-5050-5 tr 2sc5200 t0-3p (l) 3 q108, q110, q112 4860-5060-5 tr 2sa1943 t0-3p (l) 3 q103, q107, q109 4860-8890-0 tr mps a06 vce 80v ns 1 q5 8910-0062-0 ce 80v 4700u 20% rl 25x 2 c120, c121 8910-0274-0 thermal ptc 60c 100 ohm 1 r7 8910-0488-0 rod thermistor ntc 50ohm 1 ...

  • Page 19

    Rmx series technical service manual 17 4860-5030-5 tr mje15033 1 q206 4860-5050-5 tr 2sc5200 t0-3p (l) 3 q208, q210, q212 4860-5060-5 tr 2sa1943 t0-3p (l) 3 q203, q207, q209 8910-0062-0 ce 80v 4700u 20% rl 25x 2 c220, c221 8910-0274-0 thermal ptc 60c 100 ohm 1 r4 8910-0488-0 rod thermistor ntc 50ohm...

  • Page 20

    18 qsc audio products, inc. 6.2 rmx 1450 replacement parts qsc part # description qty. Notes or component reference misc. 1806-2506-0 power transformer, 1200 1 2113-1144-0 ac inlet 1 4134-9101-0 metal wind guide 1 4154-0361-0 fan guide 1 5200-4717-0 rocker power switch 1 5200-3531-0 circuit breaker ...

  • Page 21

    Rmx series technical service manual 19 8910-0274-0 thermal ptc 60c 100 ohm 1 r7 8910-0488-0 rod thermistor ntc 50ohm 1 r134 channel 1 smt parts 150f-222k-6-cf cc 50v 2200pf 10% 1206 1 1 c115 150h-102j-6-cf cc 100v 0.001u 5% 1206 1 c114 4720-103j-j rmg 1/10w 10k 5% 0805 1 r128 4720-152j-j rmg 1/10w 1...

  • Page 22

    20 qsc audio products, inc. 8910-0274-0 thermal ptc 60c 100 ohm 1 r4 8910-0488-0 rod thermistor ntc 50ohm 1 r234 channel 2 smt parts 150f-104k-6-cf cer2 1206 x7r 50v 100n 3 c100, c102, c104 150f-181k-j-bd cc 50v 180p 10% 0805 4 c101, c103, c201, c203 150f-222k-6-cf cc 50v 2200pf 10% 1206 1 1 c215 15...

  • Page 23

    Rmx series technical service manual 21 6.3 rmx 2450 replacement parts qsc part # description qty. Notes or component reference misc. 1806-2507-0 power transformer, 1800 1 2113-1144-0 ac inlet 1 4134-9101-0 metal wind guide 1 4154-0361-0 fan guide 1 5200-4717-0 rocker power switch 1 5200-3531-0 circu...

  • Page 24

    22 qsc audio products, inc. 4718-153j-2-x rmf 1w 15k 5% at metal 1 r165 4718-220j-2-p rmf 1w 22r 5% at fp 2 r136, r137 4718-3r3j-1-x rmf 1w 3.3r 5% al 3 r146, r147, r20 4719-1r5j-1-x rmf 2w 1r5 5% al metal 2 r181, r182 4719-5r6j-1-x rmf 2w 5.6r 5% al metal 1 r160 471a-022k-5-n rmf 3w 0.22r 10% rl rg...

  • Page 25

    Rmx series technical service manual 23 4720-472j-j rmg 1/10w 4.7k 5% 0805 8 r114, r138, r174, r179, r187, r193, r214, r238 4720-473j-j rmg 1/10w 47k 5% 0805 1 r183 4720-474j-j rmg 1/10w 470k 5% 0805 2 r172, r185 4720-592a-j rmg 1/10w 5.9k 1% 0805 2 r171, r184 4720-750j-j rmg 1/10w 75r 5% 0805 1 r124...

  • Page 26

    24 qsc audio products, inc. 4860-5020-5 tr mje15032 1 q205 4860-5030-5 tr mje15033 1 q206 4860-5050-5 tr 2sc5200 t0-3p (l) 4 q204, q208, q210, q212 4860-5060-5 tr 2sa1943 t0-3p (l) 4 q203, q207, q209, q211 4860-5250-5 tr 2n5064 triode 2 d219, d220 4860-8890-0 tr mps a06 vce 80v ns 1 q5 490f-z440-5 f...

  • Page 27: 7. Schematics and Diagrams

    Rmx series technical service manual 25 dwg no. P a-002450-00 1 sh rev 8 7 6 5 4 3 2 1 8 7 6 5 4 3 2 1 a b c d a b c d this document contains proprietary information which is the property of qsc audio products, that may not be disclosed, reproduced or used without express written consent from qsc aud...

  • Page 28

    26 qsc audio products, inc. Chassis screw 4 reqd wire assy nut screw 5 reqd screw 6 reqd knob 2 reqd d scale 1/2 sheet 2 of 2 dwg no. Pa-002450-00 rev dwg no. P a-002450-00 2 sh rev 8 7 6 5 4 3 2 1 8 7 6 5 4 3 2 1 a b c d a b c d this document contains proprietary information which is the property o...

  • Page 29

    Rmx series technical service manual 27 gray shading indicates signal path notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d qsc audio products. Without express written consent from be disclosed, reproduced or used of qsc audio products, that may not information which is the property this doc...

  • Page 30

    28 qsc audio products, inc. Gray shading indicates signal path notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d this document contains proprietary information which is the property of qsc audio products, that may not be disclosed, reproduced or used without express written consent from qsc ...

  • Page 31

    Rmx series technical service manual 29 notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d this document contains proprietary information which is the property of qsc audio products, that may not be disclosed, reproduced or used without express written consent from qsc audio products. C d 1 4 ...

  • Page 32

    30 qsc audio products, inc. Gray shading indicates signal path notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d qsc audio products. Without express written consent from be disclosed, reproduced or used of qsc audio products, that may not information which is the property this document conta...

  • Page 33

    Rmx series technical service manual 31 gray shading indicates signal path notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d this document contains proprietary information which is the property of qsc audio products, that may not be disclosed, reproduced or used without express written consen...

  • Page 34

    32 qsc audio products, inc. ! ! ! ! ! ! ! Notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d this document contains proprietary information which is the property of qsc audio products, that may not be disclosed, reproduced or used without express written consent from qsc audio products. C d 1...

  • Page 35

    Rmx series technical service manual 33 gray shading indicates signal path notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d qsc audio products. Without express written consent from be disclosed, reproduced or used of qsc audio products, that may not information which is the property this doc...

  • Page 36

    34 qsc audio products, inc. Gray shading indicates signal path notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d this document contains proprietary information which is the property of qsc audio products, that may not be disclosed, reproduced or used without express written consent from qsc ...

  • Page 37

    Rmx series technical service manual 35 ! ! ! ! Notes: unless otherwise specified a b 8 7 6 5 8 6 7 5 c d qsc audio products. Without express written consent from be disclosed, reproduced or used of qsc audio products, that may not information which is the property this document contains proprietary ...

  • Page 38

    36 qsc audio products, inc. Ch 1 spkr output ch 2 spkr output ch 1 spkr common ch 2 spkr common j103 j203 output pcb 1724-340c-0102 jp14 jp13 jp15 jp16 red blk wiring diagram, rmx 850 audio products, inc. Costa mesa, california scale none rev a sheet 1 of 1 notes: unless otherwise specified rev desc...

  • Page 39

    Rmx series technical service manual 37 ch 1 spkr output ch 2 spkr output ch 1 spkr common ch 2 spkr common j103 j203 output pcb 1724-340c-0102 jp14 jp13 jp15 jp16 red blk wiring diagram, rmx 1450 audio products, inc. Costa mesa, california scale none rev a sheet 1 of 1 notes: unless otherwise specif...

  • Page 40

    38 qsc audio products, inc. Ch 1 spkr output ch 2 spkr output ch 1 spkr common ch 2 spkr common j103 j203 output pcb 1724-342a-0102 jp14 jp13 jp15 jp16 red 5 red 4 blk 3 blk 2 blk 1 fg-002450-00 rmx 2450 next assy used on first application unless otherwise specified dimensions are in inches wiring d...

  • Page 42

    “qsc” and the qsc logo are registered trademarks of qsc audio products, inc. 1675 macarthur blvd. Costa mesa, ca 92626 (800) 772-2834 fax (714)754-6173 www.Qscaudio.Com.