Test Equipment Required For Servicing; Am Alignment Procedure - Marantz QUADRADIAL 4 Service Manual

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5. Improper clipping
a. Check for defective resistor, R662 & R663.
8. TEST EQUIPMENT REQUIRED FOR SERVICING
Table 1 lists the test equipment required for servicing the Model 4430 Receiver.
Item
Manufacturer and Model No.
AM Signal Generator
Test Loop
FM Signal Generator
Less than 0.3% distortion
Stereo Modulator Less than 0.3% distortion
Audio Oscillator Weston Model CV0-100P, less
than 0.02% residual distortion
is required.
Oscilloscope High sensitivity with DC hori-
zontal and vertical amplifiers.
VTVM With AC, DC, RF range
Circuit Tester
AC Wattmeter Simpson, Model 390
AC Ammeter Commercial Grade (1-10A)
Line Voltmeter Commercial Grade
(0-150V AC)
Variable Autotransformer Powerstat, Model 116B
(0-140V AC, 10 amps)
Shorting Plug Use phono plug with 600
ohm across center pin and
shell.
Output Load Commercial Grade
(8 ohms,± 1 % 1 OOW)
Output Load Commercial Grade
(4 ohms,
±
1 % 1 OOW)
Use
Signal source for AM align-
ment.
Used with AM Signal gen-
erator.
Signal source for FM align-
ment.
Stereo separation alignment
and trouble shooting.
Sinewave and squarewave sig-
nal source.
Waveform analysis and trouble
shooting and ASO alignment.
Voltage measurements.
Trouble shooting.
Monitors primary power to
Amplifier.
Monitors amplifier output un-
der short circuit condition.
Monitors potential of primary
power to amplifier.
Adjusts level of primary
power to amplifier.
Shorts amplifier input to
eliminate noise pickup.
Provides 8-ohm load for
amplifier output termination.
Provides 4-ohm load for
amplifier output termination.
Table 1 Test Equipment Required for Servicing
9. AM ALIGNMENT PROCEDURE
9.1 AM IF Alignment
1. Connect a sweep generator to the J 151 and an alignment scope to the J 162.
2. Rotate each core of IF transformer L 153 and L 154 for maximum height and flat top sym-
metrical response.
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