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Preliminary Information
Unless there is evidence of tempering or if electrical repairs
have been made tuner alignment is normally not required.
"A"
is an indicator of the quality of tuner
Response Curve
performance. If the response curve is obviously bad on all
channels, repair, rather than alignment, is indicated.
Also check for bad solder connections and contacts.
Visually inspect the circuits for overheated components
and obvious wiring defects.
Equipment Connections:
Test
GENERAL . . . . The set under -test should be correctly
performing this tuner check.
TUNER PERFORMANCE CHECK
Refer to Figure 6.
Response Curve "A"
Figure 6. Tuner Performance Check
OSCILLOSCOPE . . . With at 1 .OV P-P calibration, connect
to terminal TP203.
SWEEP GENERATOR . . . ..Connect output to the tuner
aerial terminals using proper matching pad.
MARKER GENERATOR . . . . . . . . Connect markers at loosely
to Sweep Generator output lead.
BIAS SUPPLY . . . . . . . . . . . . . . . . Apply +7.S volts bias to TP204.
Performance Check
Starting with the tuner placed in the Channel 12 position
and the Sweep Generator .set at the proper frequency, check
the overall response curve as viewed on the Oscilloscope.
This viewed curve should match, approximately, Response
Curve "A".
The same procedure should be used for
Channels 11 through 0.
.
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Troubleshooting
