Web: http://www.qscaudio.com (product information and support) http://www.qscstore.com (parts and accessory sales) Copyright 2001, 2002, 2005, 2008 QSC Audio Products, LLC All rights reserved. Document # TD-000098-00, Rev. C. Released June 2008. RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
1.1 Restriction of Hazardous Substances Directive (RoHS) Since April 2006, all RMX Series amplifiers are manufactured to conform to the European Union’s RoHS Directive, which reduces the amount of hazardous substances allowed in products for sale within its member nations. In electronic equipment such as audio power amplifiers, this applies primarily to certain toxic heavy metals, such as lead, which may be present in electronic components, solder, and other parts.
• • Diagonal cutters • Wire strippers Automated test equipment, such as an Audio Precision workstation, is very useful for servicing RMX amplifiers. Contact QSC Technical Services to obtain applicable AP test files. 1.5 Working with surface-mount components RMX amplifiers, like many modern electronic products, use surface-mount technology (SMT) components where appropriate in order to make high-density circuitry that is reliable and economical to manufacture.
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3 Hold the component in place and take the soldering iron away. Let the solder harden to tack the component in place. 4 Fully solder the other terminals of the component to their pads. Let the solder harden. 5 Fully solder the tacked terminal of the component to its pad. RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
Power supplies sensors. Unlike other recent QSC amplifiers, the RMX line uses strictly Audio circuitry conventional power supplies, with large transformers that operate at the 50 or 60 Hz frequency of the AC line. The electrical current...
^R_0805 When the clipping stops, Q100 is no longer forward-biased, and Q100 CLIP LIMIT the gain returns to normal. 3906 SWITCH (Open to defeat clip limiter) -14V Figure 1.12 RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
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A protection circuit monitors the balance between Channel 1’s and Channel 2’s signals. Resistors R22 and R23 (R22A, R22B, R23A, and R23B on the RMX2450) are equal in value and QSC Audio Products, LLC...
(part number IC-000213-GP; was 3130-9270-0) K A G IRFZ44 TMOS power field effect transistor (part number QD-000347-GP; was 490F-Z440-5) 2N3904 (NPN) Small-signal transistor (part number QD-000204-GP; was 4860-0640-3) 2N3906 (PNP) Small-signal transistor (part number QD-000205-GP; was 4853-9060-3) RMX Series Technical Service Manual...
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Note: To install the BTA41 Triac on a channel module circuit board that originally held a MAC224 Triac, first mount it to an adapter (QSC part number SR-000117-00) and then solder the adapter to the circuit board. See Service Bulletin RMX0008 for more information.
D8 and R10; also, C7 and C8 is leaky. • Bias diodes D108, D109, D208, or D209 or bias trimpots R131 or • D9, R4, and/or R7 is open. R231 is open. RMX Series Technical Service Manual...
• Check C114, C124, C214 and C224. • Severe distortion, at any load, often with abnormally high • Check or replace dual op amp U101 or U201. current draw: check the slew rate capacitors C114, C115, and QSC Audio Products, LLC...
R240 permit adjustment of the current limit thresholds. See voltage divider is the likely culprit. the RMX calibration section of this manual for adjustment procedures. RMX Series Technical Service Manual...
AC wires and check the amp’s idle current. If the amplifier is still at about room temperature, the idle current should match the value shown in Table 1. QSC Audio Products, LLC...
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Idle AC demand* (at ambient temperature; 0.4 A, 0.4 A, 0.6 A, 0.6 A, ±10% ±10% ±10% ±10% higher when hot) *Figures shown are for 120V amplifiers; multiply current by 0.5 for 230V or 1.2 for 100V. RMX Series Technical Service Manual...
QSC’s factory service. Any other operating voltage module is Channel 1 and the right is Channel 2 except in the conversions may be done only by a QSC-authorized service center RMX2450; its right module is Channel 1, and its left is Channel 2.
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RMX850 Channel 1 Module Assembly (continued) QSC part # Old QSC part # Description Qty. Notes or Component Reference RE-000260-GP 8910-0274-0 THERMAL PTC 60C 100 OHM RE-001201-GP 471B-120J-1-X 12 5% 5W METAL OXIDE FILM R161, R162 RE-002202-GP 4718-220J-2-P RMF 1W 22R 5% AT FP...
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J100, J200 PA-000043-00 2113-1338-0 PLATE ASSY,PLX/RMX,OUTPUT,, J103 PL-000055-00 4154-2111-0 OUTPUT POST PLUG FOR CE (RED) For European models only PL-000056-00 4154-2121-0 OUTPUT POST PLUG FOR CE (BLACK) For European models only RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
6.2 RMX1450 Replacement Parts QSC part # Old QSC part # Description Qty. Notes or Component Reference Misc. CH-000194-GP 4134-9101-0 FAN SHROUD RMX CO-000211-GP 2113-1144-0 AC INLET 250V 15A MS-000137-GP 4154-0361-0 FAN GUARD WIRE 76MM RMX MS-000138-GP 8900-9050-1 DC FAN 24V 80X80 (+5V)
TRIM POT,100,20 PCNT,0.15W,, R131 PT-225000-GP 4751-0110-0 RES VAR 2.5K RT ANGLE PCB R112, R212 QD-000197-GP 3700-4529-R LED 4.7MM RED W/STAND LD100, LD200 QD-000199-GP 3700-4530-Y LED 4.7MM W/STAND YELLOW LD101, LD201 RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
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RMX1850HD Channel 1 module (continued) QSC part # Old QSC part # Description Qty. Notes or Component Reference QD-000202-GP 4804-0040-1 DIODE IN4004 AL D10, D12, D117, D118 QD-000203-GP 4838-15V6-2 DIOD ZNR 15V 1W SILICON EPIT D100, D101, D200, D201 QD-000206-GP...
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2113-1336-1 SPEAKON NEUTRIK 4 WIRE J100, J200 PA-000043-00 2113-1338-0 PLATE ASSY,PLX/RMX,OUTPUT,, J103 PL-000055-00 4154-2111-0 OUTPUT POST PLUG FOR CE (RED) For European models only PL-000056-00 4154-2121-0 OUTPUT POST PLUG FOR CE (BLACK) For European models only QSC Audio Products, LLC...
SEE TABULATION BLOCK DWG NO. RMX 2450 FINISH ISSUED PA-002450-00 (All models) NOTES: UNLESS OTHERWISE SPECIFIED NEXT ASSY USED ON SCALE SHEET APPLICATION DO NOT SCALE DRAWING 1 OF 2 RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION WHICH IS THE PROPERTY OF QSC AUDIO PRODUCTS, THAT MAY NOT BE DISCLOSED, REPRODUCED OR USED CHANNEL MODULES WITHOUT EXPRESS WRITTEN CONSENT FROM QSC AUDIO PRODUCTS. RMX 850: WP-008503-00; was PCB-QZ010C-PWR1 (left or Channel 1) RMX 1450: WP-014502-00;...
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. CHANNEL-2 C201 180p-5% ^C_0805 R205 R228 R229 Q201 +VCC_B R235 +67V 3904 10.0K...
REVISION THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION WHICH IS THE PROPERTY DESCRIPTION EFF. DATE APPROVED / DATE OF QSC AUDIO PRODUCTS, THAT MAY NOT BE DISCLOSED, REPRODUCED OR USED PROTOTYPE RELEASE 3-01-00 WITHOUT EXPRESS WRITTEN CONSENT FROM QSC AUDIO PRODUCTS. CLEAN UP BY PHQ...
POS STEP DRIVER THIS DOCUMENT CONTAINS PROPRIETARY +110_A INFORMATION WHICH IS THE PROPERTY C170 OF QSC AUDIO PRODUCTS, THAT MAY NOT BE DISCLOSED, REPRODUCED OR USED 47pF-50V-5% WITHOUT EXPRESS WRITTEN CONSENT FROM Q170 ^Q_BJTN_SOT-23 R170 QSC AUDIO PRODUCTS. ^C_0805 RFZ44...
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. CT_A SEE SH 1 J104:12 J21:1 RECTIFIER BR100-201 CIRCUIT +14V IS DRAWN FOR CHASSIS MTG...
THIS DOCUMENT CONTAINS PROPRIETARY REVISIONS INFORMATION WHICH IS THE PROPERTY DESCRIPTION EFF. DATE APPROVED/DATE OF QSC AUDIO PRODUCTS, THAT MAY NOT BE DISCLOSED, REPRODUCED OR USED OUTPUT PCB WITHOUT EXPRESS WRITTEN CONSENT FROM QSC AUDIO PRODUCTS. 1724-340C-0102 J103 E100 JP14...
7.19 RMX1850HD and RMX2450 Chassis Wiring Diagram DWG NO. FG-002450-00 RMX 2450 ISSUED SH-002450-00 NOTES: UNLESS OTHERWISE SPECIFIED NEXT ASSY USED ON SCALE SHEET FIRST APPLICATION NONE 1 OF 1 DO NOT SCALE DRAWING RMX Series Technical Service Manual (2RU models) TD-000098-00 rev. C...
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“QSC” and the QSC logo are registered trademarks of QSC Audio Products, LLC 1665 MacArthur Blvd. Costa Mesa, CA 92626 Phone +1 (714) 957-7150 (800) 772-2834 (USA only) FAX +1 (714)754-6173 www.qscaudio.com...