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MPA4-150 SERVICE MANUAL CHANNEL 1 CHANNEL 2 CHANNEL 3 CHANNEL 4 4-150 CLIP SP CLIP SP CLIP CLIP POWER MULTICHANNEL POWER AMPLIFIER...
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SERVICE MANUAL MPA4-150 INDEX - BLOCK DIAGRAM - SCHEMATICS - COMPONENTS LOCATION SCHEMA AND PART LIST - TESTING AND QUALITY CONTROL - TECHNICAL CHARACTERISTICS - WIRING DIAGRAM - MECHANICAL DIAGRAM - PACKING DIAGRAM...
J. Colomines 050401 ECLER EP05-99 MPA4-150 author: date: project: product: approved: title: FUNCTIONING DESCRIPTION 52.0006 01.01 num: version: The amplifying stage basic structure is actually the one commonly used until now, this is, a push-pull mounted A-B class amplifier, using P-type (IRFP9240) and N-type (IRFP240) mosfets.
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Moreover, the amplifier also includes an ANTICLIP system. When the amplifier reaches its clipping level, the OpAmp becomes unable to keep the system under control, and as a consequence ±V peaks appear at its output (15V power supply). This peaks are used to be rectified and sent to an optocupler (led-resistor) which modifies its impedance as a function of those peaks' amplitude.
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Queralt 000719 FUNCTIONING DESCRIPTION ECLER author: date: approved: title: EP05-99 52.0006 01.00 num: version: The amplifying stage basic structure is actually the one commonly used until now, this is, a push-pull mounted A-B class amplifier, using P-type (IRFP9240) and N-type (IRFP240) mosfets.
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Queralt 000719 FUNCTIONING DESCRIPTION ECLER author: date: approved: title: EP05-99 52.0006 01.00 num: version: Moreover, the amplifier also includes an ANTICLIP system. When the amplifier reaches its clipping level, the OpAmp becomes unable to keep the system under control, and as a consequence ±V peaks appear at its output (15V power supply).
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Announcement addressed to Technical Support Services Involved series: APA1400 / APA1000 / APA600 PAM1100 / PAM2100 MPA4-80 / MPA6-80 / MPA4-150 VOLUME potentiometer replacement. Replaced service part code: FCPR210040 When this potentiometer is being replaced, after soldering it on the printed circuit board, the two leads should be shorted as shown in the picture, in order to ensure a correct performance depending on the available service part.
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Queralt 000718 VERIFICATION PROCESS ECLER author: date: approved: title: EP05-99 51.0023 01.00 num: version: PRELIMINARY - Check the Ground Link. - Have a look at the unit's mains cable, inputs, outputs and other cables and connectors. - Check out that there are no shortings between the unit’s mounting frame, mains carriers, and outputs.
Queralt 000718 VERIFICATION PROCESS ECLER author: date: approved: title: EP05-99 51.0023 01.00 num: version: signal level until the output signal clips. At this point, a two- or three-cycled ripple should appear on the flat sections of the square waveform. Repeat this same process with channel two.
Queralt 000718 VERIFICATION PROCESS ECLER author: date: approved: title: EP05-99 51.0023 01.00 num: version: other oscillations. - Repeat the same process with the remaining channels. QUALITY CONTROL All mechanical parts should be visually revised, in order to detect scratches on the unit's painting;...