Crown Audio 1200 service manual Positive

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Micro-Tech 1200 Amplifier Service Manual

Theory

					POSITIVE
			+VOLTAGE	+LVA	HIGH SIDE
			TRANSLATOR	-1	OUTPUT
					NPN STAGE
BGS		VGS	ERROR
BGS		VGS	AMP
			AMP
			OUTPUT		HIGH SIDE
BALANCED			DEVICE		HIGH SIDE
	-1		DEVICE		BIAS
			EMULATION
INPUTS
					SERVO
			PROTECTION


				-LVA	NEGATIVE
			-VOLTAGE	-LVA	HIGH SIDE
			TRANSLATOR	-1	OUTPUT
					PNP STAGE
				MAIN NEGATIVE FEEDBACK (NFb) LOOP
					POSITIVE
					LOW SIDE
					OUTPUT
					NPN STAGE
					LOW SIDE
				-1	BIAS
				-1	DIODE
					DIODE
					STRING
					NEGATIVE
				INVERTING	LOW SIDE
				BRIDGE	OUTPUT
				BALANCE	PNP STAGE

Figure 3. Typical Crown Amplifier Basic Block Diagram (One Channel Shown)

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Contents MICRO-TECH-1200 Avis Table of Contents Warranty IntroductionScope Parts Information Specifications PowerVoltage Conversion Features TheoryOverview Front END OperationVoltage Amplification Grounded Bridge TopologyLast Voltage Amplifiers LVAs Voltage TranslatorsHigh Side HS Low Side LSOutput Device Emulation Protection Odep Positive Electrical Checkout Procedures Test 2 Output Bias AdjustmentTest 3 Odep Voltage Adjustment Standard Initial ConditionsTest 4 AC Power Draw Test 5 Common Mode RejectionTest 7 Phase Response Test 12 Output PowerTest 16 Signal to Noise Ratio Test 13 Reactive LoadsTest 14 Odep Limiting Test 15 LF ProtectionPost Testing Test 19 Intermodulation DistortionTest 20 Clipping Spec at 0 dB Output 0.01% Spec at -35 dB Output 0.05%Parts List Non-Module Power SupplyOutput Assembly ONE PER Channel Supplimental ItemsOutput Assembly Back Panel AssemblyChassis Front Assembly Main Chassis AssemblyParts List Non-Module Module and Schematic Information Fuse and Display Module Parts Lists Q42549-8 Output Module P10115-7 board Parts List Q42647-0 Output Module P10137-1 board Parts List Q42717-1 Output Module P10233-8 board Parts List Q42871-6 Output Module P10305-4 board Parts List Q42968-0 Output Module P10341-9 board Parts List Q43202-3 Output Module P10397-1 board Parts List Q42552A0 Main Module D6304A4/D6304B2 board Parts List Resistor NetworksSwitches ConnectorsIntegrated Circuits Mounts U1, U2Q42714-8 Main Module D 6910-0 board Parts List Dpdt Q42776-7 Main Module D 7251-8 board Parts List OpenQ42776-7 Main Module D 7251-1 board Parts List HDR, 5 PIN Q42980-5 Main Module D7911-7 board Parts List Resistors DP3T Q43035-7 Main Module D7993-5 board Parts List NPN MPS8097Jumper IC’S Q43031-6 Main Module D7993-5 board Parts List Resistor Networks Switches