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WHAT
TO DO IF?
There can be a variety of problems due to the mis-handling of the control amplifier.
When a problem occurs, please check the table below which describes possible problems occurring in your con-
trol amplifier.
Since the contro! amplifier is completely checked and adjusted before shipping, there are no user serviceable and
adjustable parts inside. But if the control amplifier is not operating correctly and you are unable to restore nor-
mal operation by following the detailed procedure in the table below, do not remove the back cover of the set or
attempt any further adjustments. Unplug the sét and contact your dealer or nearest Hitachi service station.
SYMPTOM
a
REMEDY
Power indicator does not come
Line plug is loose.
1.
Plug the AC plug into AC outlet.
on and the sound is not heard
Fuse blown.
2.
Replace the fuse.
although the power switch is
set to ON.
Power indicator comes on but
the sound is not heard.
1. The speaker cords are loose.
3
2. The tape switch is set to TAPE-1
or TAPE-2.
The speaker cord of one channel
is loose.
2. BALANCE
control is turned
fully clockwise or counterclock-
wise.
Sound separation is not distinct
Polarities of the speaker connec-
Correct the polarities on either the
and bass is poor.
tions are not aligned properly.
"speakers,
The sound of both channels or
Faulty connection of the output
Connect the output cords of the turn-
one channel is not heard.
cords of the turntable.
table to the control amplifier securely.
Hum and buzz.
.
Faulty connection of the output
1. Connect the output cords of the turn-
cords of turntable.
table to the control amplifier securely.
2.
Pin jack connection is loose.
2. Secure the pin-plug to the pin-jack.
3. Ground wire is loose.
3. Connect the ground wire of the turn-
4. There is a line cord near the out-
table to GND terminals of the control
put cords of turntable.
amplifier.
4. Separate the line cord from the output
cords of the turntable.
Connect the speaker cords to the speaker
terminals.
2. Set the tape switch to SOURCE.
1.
ie
Only one channel works.
Connect the speaker cord to the speaker
terminals.
2. Set the BALANCE
control to the mid-
way position.
NORMAL
PLAYING
Increasing the volume causes
howl.
1. Sound of the speakers is making
the turntable vibrate.
1. Move either the speakers or turntable.
Do not increase the BASS sound level
excessively.
PLAYING
RECORDS
Output tone is mixed with noise
and treble is not clear.
1. Stylus is worn out.
2.
Record is worn out.
3. Dust is adhering to stylus.
4. Stylus is improperly mounted.
5. Tracking force is not correct.
6. The TREBLE sound is too high.
1. Static.
2.
Noise caused by other electric
appliances.
Correct the conditions described in 1-6.
Continuous noise in AM.
Set up a good and high outdoor antenna
and ground it perfectly.
Only when tuning AM broad-
1.
casts, hum noise is heard.
Generally caused by high voltage
By reversing the polarity of AC plug,
lines or other electric appliances.
the hum is reduced, But it is very diffi-
cult to remove this noise completely.
Continuous or intermittent
noise.
1.
Ignition noise from automobile
engines.
Set up an outdoor FM antenna in-
stead of using attached FM feeder
antenna.
The sound of FM program con-
tains noise like zzz. More noise
is included in FM stereo recep-
tion than FM mono.
1.
The signal input of antenna ter-
minals is too weak to receive FM
stereo broadcasts.
Set up an outdoor FM antenna.
LISTENING
TO
BROADCASTS
Operation procedure for power switches
The HCA-7500
incorporates a muting circuit to safeguard against shock noise. Nevertheless, you can still
Switching the power on
Switching the power off
Control amplifier's volume control
Minimum
|
Control amplifier's volume control
Minimum
Power amplifier's speaker switch
OFF
| Power amplifier's speaker switch
OFF
Control amplifier's power switch
ON
| Power amplifier's power switch
OFF
Power amplifier's power switch
ON
|
Contro! amplifier's power switch
OFF
Power amplifier's speaker switch
ON
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