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3-5
Does the customer select correctly
the AM/FM function he or she wants to listen to?
Make sure to connect AM/FM antennas
on the rear panel of the unit.
YES
NO
Is “AM or FM” displayed on VFD?
Make sure to select AM or FM function
pressing the TUNER button.
YES
NO
After tuning a desired channel
using the TUNING± button,
is the sound quality good to listen to the music?
To prevent noise pickup, keep the AM Loop
antenna away from the unit and other components.
Be sure to fully extend the FM wire antenna. After
connecting the FM wire antenna, keep it horizontal.
YES
NO
Is the signal strength of the radio station too week?
Make sure to tune the station manually.
YES
NO
Are the sound spectrum level LED’s
on the left and right side of the front panel
being changed up and down
according to the sound input gain?
The sound spectrum level LED’s will be turned on/off
repeatedly at regular intervals. A speaker cable might
be short-circuited with the chassis ground.
Be careful not to be shorted each other.
YES
NO
Are the speaker cables connected correctly
between the speaker terminals on the unit
and the speakers?
Make sure to connect the cables to each specified
connector tightly on the unit.
Connect the woofer cables to the WOOF SYSTEM
connectors on the rear panel.
YES
NO
The sound is output from the speakers.
YES
Sound OK
4. NO SOUND IN AM/FM FUNCTION
TRAINING MASTER
Summary of Contents for CM7420
Page 13: ...1 12 MEMO ...
Page 15: ...2 2 MEMO ...
Page 19: ...A60 4 SPEAKER SECTION FRONT SPEAKER CMS7520F ...
Page 82: ...3 79 3 80 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 84: ...3 83 3 84 2 MAIN P C BOARD TOP VIEW ...
Page 85: ...3 85 3 86 MAIN P C BOARD BOTTOM VIEW ...
Page 86: ...3 87 3 88 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...
Page 87: ...3 89 3 90 4 FRONT_MIC PORTABLE P C BOARD TOP VIEW BOTTOM VIEW ...
Page 88: ...3 91 3 92 5 FRONT_VOLUME P C BOARD TOP VIEW ...
Page 89: ...3 93 3 94 FRONT_VOLUME P C BOARD BOTTOM VIEW ...