Sansui TU 666 Service Manual

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OPERATING INSTRUCTIONS
& SERVICE MANUAL

SOLID-STATE AM/ FM STEREO TUNER

SANSlII Ill-666
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SANSUI ELECTRIC CO., LTD.

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Congratulations, you are now the owner of the new Sansui TU-
666 solid state stereo tuner built for exceptional performance by
the worlds foremost audio-only specialist. Designed specifically
for FM enthusiasts, the TU-666 will pull in an increasing number
of FM stations more clearly in either strong signal areas or fringe
locations. Its highly sensitive FET front end and IC-equipped
i.f. strip Show a new degree of selectivity by permitting weak
signals to be tuned Without being blanketed by adjacent strong
signals. In the AM section, the exclusive ceramic filter upgrades
its performance characteristics. The refined dull black panels are
common to all AU series professional control amplifiers from
Sansui.

From the superior performance characteristics to the carefull fin-
ish of panels7 Sansuis tradition of quality is evident Packed
with the most advanced circuits throughout, The TU-666 comes
to you with the full confidence and guarantee of the manufacturer.
It is now up to you to read the contents of this manual carefully
before setting out to use it, so you may operate it correctly and
obtain the maximum performance it is capable of offering for
many years to come.

CONTENTS

OPERATING INSTRUCTIONS

SWITCHES AND CONTROLS .................................... 3
CONNECTIONS .................................................... 4
ANTENNA CONNECTIONS / OPERATIONS .................. 5
MAINTENANCE .................................................... 6
SPECIFICATIONS / CHARACTERISTICS .................... 7
SERVICE MANUAL
DISASSEMBLY PROCEDURE .................................... 8
BLOCK DIAGRAM ................................................ 9
ALIGNMENT .......................................... 10, 11, 12, 13
PRINTED CIRCUIT BOARDS AND PARTS LIST
.................................... 14, 15, 16, 17, 18, 19
ACCESSORIES LIST .............................................. 19
OTHER PARTS AND THEIR POSITION 0N CHASSIS
.................................................... 19, 20

GENERAL TROUBLESHOOTING CHART .............. 21, 22

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GENERAL TROUBLESHOOTING CHART

If your AM and/or FM stereo listening isnt all
youd expected, it is in many cases that the tuner
The trouble may attributed to the

is not at fault.
following:

1. Incorrect component connection or loose termi-

nal contact;

In some instances, the amplifier which is operating satisfactorily
develops hum or noise as listed on this page. In this case, elimi-
nate the trouble source as indicated in the column under WHAT

TO DO.

If you are confronted with a trouble not covered here or if you
have any questions concerning the operation and maintenance
of this amplifier, please contact our Customer Service Depart-

ment.

2. Incorrect or improper operation of tuner and/or
other components;
3. Improper location of components;

4. Other component or components defective.

Other probable causes are listed below:

PROGRAM

SYMPTOM

PROBABLE CAUSE

WHAT TO DO

AM, FM mono
or FM stereo

A. Constant or intermitt-
ent noise heard at
times or in a certain
area

* Discharge or oscillation
caused by electrical appli-
ances, such as fluorescent
lamp, TV set, DC. motor,
rectifier and oscillator

* Natural phenomena, such
as atmospherics, statics,
strays and thunderbolt

* Insufficient antenna input
due to thick reinforced
concrete wall of a building
or long distance from the
station

* Wave interference from
other electrical appliances

* Attach a noise limiter to the
electrical appliance that causes the
noise. or attach it to the power
source of the amplifier.

* Install an outdoor antenna and
ground the amplifier to raise the
signal-to-noise ratio.

* Reverse the power
receptacle connections.

cord plug-

* If the noise occurs at a certain
frequency, attach a wave trap to the
ANTi input.

* Keep the set in proper distance from
other electrical appliances.

Bi The needle of the
tuning meter does not
move well.

The movement of the needle
is one thing. the sensitivity of
the amplifier is another.

Turn the set for maximum signal
strength.

C. The zero point of the
meter diverges much.

Regional difference in field
intensity

The unit is not at fault.

AM

A. Noise heard at a par-
ticular time of a day,
in a certain area or
over part of dial

This results from the nature of
AM broadcast.

* Install the antenna for maximum
antenna efficiency.

* In some cases, the noise can be
eliminated by grounding the ampli-
fier or reversing the power cord '
plug-receptacle connections.

B. High-frequency noise

* Adjacent-channel interfer-
ence or beat interference

* TV. set too close to the
audio system

* Although such noise cannot be
eliminated it is advisable to switch
on the noise filter of the amplifier.

* Keep the TV set in proper distance
from the audio system.

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