Marantz 1060 Service Manual page 7

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8. PERFORMANCE VERIFICATION
Test Procedure
A. Test Equipment
Refer to Table 1 for required test equipment.
B. Preliminary Procedures
ie
3.
4,
Make the test setup shown in Figure 1 with the instrument controls set in the following
positions:
Line Switch | off
V ariable-line switch variable
Watt Meter Switch on
Variac 0 (fully CCW)
Load 8 ohms (0.5 mfd - off)
Audio Generator Frequency 1 KHz
Output 5V range
Gain Minimum
AC Volt Meter 30V range
Make sure that connections between the resistive load and the system terminals of the
Model 1060 have negligible resistance compared with the resistance of the load itself.
Appreciable resistance in wiring adds to the total load, resulting in inaccurate
measurements of output power.
Connect amplifier output to load and connect AC cord to line power. Connect a shorting
plug to the Phono input jack of the model 1060.
Remove the top cover.
C. Total Hum and Noise Test
1.
2.
3:
4.
With shorting plugs connected to the Phono input jacks and a 8-ohm resistive load
connected across the speaker system output terminals, connect a distortion analyzer
across the load.
NOTE: In this test and tests that follow, if distortion analyzer used does not contain
a built-in voltmeter, a VT VM may be substituted.
Set the distortion analyzer controls for voltage measurements and apply power to the
amplifier. Set the volume control fully CCW. Set the SELECTOR switch to PHONO.
If the distortion analyzer indicates more than 1.5mV, refer to the trouble analysis section
of this manual.
Set the volume control fully CW. If the distortion analyzer indicates more than 26mV
refer to the trouble analysis section of this manual.
D. Maximum Power Output
1.
2.
3.
Connect the audio oscillator to the AUX1 input. Set audio oscillator Trequency to 1 KHz.
Set SELECTOR switch to AUX1.
With the distortion analyzer connected across the output load ena set the analyzer
on the 30V AC scale.
Turn the analyzer on and increase the audio oscillator output to 180mV, and verify the
analyzer indicates more than 15.6V.
E. Harmonic Distortion Test
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2.
3.
4
Set the frequency of the audio oscillator and the distortion analyzer to 20 KHz.
Set the controls of the analyzer for voltage measurement on the 30-volt scale.
Adjust the audio oscillator output level until the analyzer meter indicates 15.6 volts.
Switch the distortion analyzer to Set Level — Manual mode, and adjust SENSITIVITY for
full scale reading on 0-1 scale.