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130445-1 Rev. A MA-2402 Service Manual The information furnished in this manual does not include all of the details of design, production, or variations of the equipment. Nor does it cover every possible situation which may arise during installation, operation or maintenance.
130445-1 Rev. A MA-2402 Service Manual Table of Contents 5.3.15 Intermodulation Distortion (IMD) ........5-4 5.3.16 Displays ................5-4 5.3.17 Post Testing ..............5-4 6 Parts ..................6-1 6.1 General Information ..............6-1 6.2 Ordering and Receiving Parts ..........6-1 6.2.1 Terms ..................
130445-1 Rev. A MA-2402 Service Manual ture balanced inputs with bridged and parallel mono- 1 Introduction phonic capability. Specific features vary depending on model. 1.1 Introduction 1.3 Scope This manual contains complete service information This Service Manual in intended to apply to all ver- on the Crown ®...
130445-1 Rev. A MA-2402 Service Manual Slew Rate: (Slew rates are limited to useful levels for ultrasonic/RF protection). Greater than 13 volts per microsecond. 2 Specifications Controls Enable: A front-panel push button used to turn the amplifier on and off. Level: A front-panel 31-detent rotary control for each channel used 6 Specifications to control the output level.
130445-1 Rev. A MA-2402 Service Manual transistor stages, particularly in the case of elevated temperature. Cooling: Internal heat sinks with forced-air cooling for rapid, Transformer overheating will result in a temporary shutdown of the uniform heat dissipation. affected channel; when it has cooled to a safe temperature, the Dimensions: EIA Standard 19-inch (48.3-cm) rack mount width transformer will automatically reset itself.
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130445-1 Rev. A MA-2402 Service Manual –1 8 ohm 1 watt 4 ohm –2 2 ohm –3 –4 –5 –6 –7 10 K 100 K FREQUENCY (Hz) Figure 2.5 Typical Frequency Response 1400 1200 1000 8 ohm 10 K 20 K FREQUENCY (Hz) Figure 2.6 Typical Damping Factor 504.0...
130445-1 Rev. A MA-2402 Service Manual 100 – 240 VAC, 50/60 Hz Units These units have mult-tap transformers that accept 100, 3 Voltage Conversion 120, 220/230, or 240 VAC, and 50 or 60 Hz power mains. Jumpers are used to configure the power supplies for different voltages.
130445-1 Rev. A MA-2402 Service Manual ergy status, and a SPI/IOC indicator for each channel 4 Circuit Theory which indicates signal output and distortion. In general, the packaging of this model is designed for maximum watt/price/weight/size value with user friendly features. 4.1 Overview For additional details refer to the specification section, or to the applicable Reference Manual.
130445-1 Rev. A MA-2402 Service Manual 4.4.2 Last Voltage Amplifiers (LVAs) dition which in turn results in high peak output voltage. The output of the Error Amp, called the Error Signal (ES) The Voltage Translator stage channels the signal to the drives the Voltage Translators.
130445-1 Rev. A MA-2402 Service Manual The output of the +LVA drives the base of predriver the power supply to protect output devices from dan- device. Together, the predriver and driver form the first gerous reverse voltage levels. An output terminating two parts of the three-deep Darlington and are biased circuit blocks RF on output lines from entering the am- class AB.
130445-1 Rev. A MA-2402 Service Manual 4.6 Output Device Emulation Protection for example, the power supply produced a total of 70V from rail to rail (±35VDC measured from ground with no (ODEP) signal), the amplifier output would reach a positive peak To further protect the output stages, a specially devel- of +70V.
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130445-1 Rev. A MA-2402 Service Manual POSITIVE +LVA +VOLTAGE HIGH SIDE TRANSLATOR OUTPUT NPN STAGE ERROR OUTPUT HIGH SIDE DEVICE BALANCED BIAS EMULATION INPUTS SERVO PROTECTION NEGATIVE -VOLTAGE -LVA HIGH SIDE TRANSLATOR OUTPUT PNP STAGE MAIN NEGATIVE FEEDBACK (NFb) LOOP POSITIVE LOW SIDE OUTPUT...
130445-1 Rev. A MA-2402 Service Manual alignment of the amplifier, may also be very helpful in troubleshooting. For best results, tests should be per- 5 Maintenance formed in order. All tests assume that AC power is from a regulated AC source appropriate for the unit under test..
130445-1 Rev. A MA-2402 Service Manual 5.3.5 Quiescent Power Draw ODEP Voltage Chart Tolerance ±0.1V Spec: 100 watts maximum °C °F Voltage Procedure: With no input signal the amplifier should draw 95.0 10.73 no more than 100 watts from the power source. Slightly 93.2 10.66 high readings may be due to out of tolerance Output...
130445-1 Rev. A MA-2402 Service Manual 5.3.12 Fan Operation Procedure: Load each channel to 8 ohms. Inject a SMPTE standard IM signal (60 Hz and 7 kHz sine wave Spec:Continuous full speed. mixed at 4:1 ratio). Set the 60 Hz portion of the signal for 50.8 Vrms output.
130445-1 Rev. A MA-2402 Service Manual 6.2.1 Terms 6 Parts Normal terms are prepaid. Net-30 Days applies to only those having pre-established accounts with Crown. The Crown Parts Department does accept Visa or Master Card. If prepaying, the order must be packed and 6.1 General Information weighed before a total bill can be established, after which an amount due will be issued and shipment made...
130445-1 Rev. A MA-2402 Service Manual 7 Exploded View Parts 7.1 General Information This chapter includes a mechanical part list for this product. All serviceable parts and assemblies will have a Crown Part Number (CPN) listed in this chapter. The parts listed are current as of the date printed.
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MA-2402 Service Manual 130445-1 Rev. A 7.2 Chassis Assembly (Top) 7.2 Chassis Assembly (Top) Continued Refer to figure 7.1 for Location of Major Parts Refer to figure 7.1 for Location of Major Parts Item Quantity Description Part # (CPN) Item Quantity Description Part # (CPN)
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MA-2402 Service Manual 130445-1 Rev. A 7.3 Chassis Assembly (Bottom) Refer to figure 7.2 for Location of Major Parts Item Quantity Description Part # (CPN) CVR, MA2400/3600 BTM PC F12609-8 SEMS, 6-32 X .31 TORX PNHD STAR 103433-70605 8-18 X 1.375 PH PNHD ST SCR Z A10109-10822 NYL THUMBSCREW WASHER D4137-2...
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130445-1 Rev. A MA-2402 Service Manual 7.4 Heat Sink Assembly (Channel 1 and 2 are Identical) Refer to figure 7.3 for Exploded View Item Quantity Description Part # (CPN) Item Quantity Description Part # (CPN) INS, 1.38 X 13.56 PAPER D8867-0 6-32 X .312 PAN HD T15 TT TYPE W C9491-9...
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MA-2402 Service Manual 130445-1 Rev. A 7.5 Cap Shelf Assembly (Channel 1 and 2 are Identical) Refer to figure 7.4 for Exploded View Item Item Quantity Quantity Description Description Part # (CPN) Part # (CPN) 6-32X.312 PAN HD T15 TT TYPE W C9491-9 CLIP, MA2402 RECTIFIER SPRING 127467-1...
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130445-1 Rev. A MA-2402 Service Manual 7.6 Fan Assembly Refer to figure 7.5 for Exploded View Item Quantity Description Part # (CPN) Item Quantity Description Part # (CPN) 6-32 X 5/16 UNDERCUT FLTHD MSCR C7062-0 BRACKET, FAN D8439-8 6-32 X .312 PAN HD T15 TT TYPE W C9491-9 XMOTOR SEE SECTION 3...
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MA-2402 Service Manual 130445-1 Rev. A 7.7 Standard PIP Assembly Refer to figure 7.6 for Exploded View Item Quantity Description Part # (CPN) Item Quantity Description Part # (CPN) #8 X 1/4 #6 PNHD PH BZ C 7161-0 PWA, PIP2FXQ 127210-1 PANEL, PIP2FXQ 127234-1...
130445-1 Rev. A MA-2402 Service Manual 8.2.5 Relay PWA: 8 Module and Schematic Ch 1 Information 127476-1 Domestic Relay PWA on 127199-1 PWB. 127259-1 8.1 General Information Export Relay PWA on 127199-1 PWB. The schematics referenced and provided are repre- Ch 2 sentative only.
130445-1 Rev. A MA-2402 Service Manual 9 Module Parts 9.1 General Information This chapter includes electrical parts lists for this prod- uct. All serviceable parts and assemblies will have a Crown Part Number (CPN) listed in this chapter. The parts listed are current as of the date printed. Crown reserves the right to modify and improve its products for the benefit of its customers.
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130445-1 Rev. A MA-2402 Service Manual 10 Schematics The schematics referenced and provided are repre- sentative only. There may be slight variations between amplifier to amplifier. These schematics are intended to be used for troubleshooting purposes only. 102773 127108 127175 127198 127252 127494...