Sansui 2000 Service Manual

Page 1

SERVICE MANUAL

SOLID-STATE AM/ FM STEREOPHONIC TUNER AMPLIFIER

SAN SUI 2000

SANSUI ELECTRIC COMPANY LIMITED

Page 2

HOW T0 USE THIS SERVICE MANUAL

1. Look up the type of trouble you are confronted with in either
the General or Troubleshooting charts provided in this manual
from pp 3713.

2. By referring to the charts, isolate the trouble to a particular
unit or part. (See the column titled What to Do in the General
Chart and Check Point in the Troubleshooting Chart.)

3. Locate the section of the chassis (Parts Layout p. 23) in which
the parts is located by using the co-ordinates (Column D) in the
Parts List pp 31-37.

4. Using the co-ordinates given in the Parts List (Column C),
pinpoint the position of the parts in the Schematic Diagram of
Circuits, pp 19-20.

NOTE: Much of the information contained in this manual has
been prepared for use by qualified service repairmen. Please read
your Warranty thoroughly before attempting any internal adjust-
ments on your own.

CONTENTS

GENERAL SECTION ............................ 3, 4
TROUBLESHOOTING CHART
OVERALL PROGRAM SOURCES ............
FM OR FM-MPX RECEPTION ..... ..
AM RECEPTION ............................
USING WITH RECORD PLAYER OR
TAPE DECK ................................ 12, 13
OTHER PROGRAM SOURCES .......
RECORDING ON TAPE ...............
ALIGNMENT POINTS AND PROCEDURE .

SCHEMATIC DIAGRAM OF CIRCUITS ............ 19, 20
DISASSEMBLY PROCEDURE .................... 21
BLOCK DIAGRAM OF PRINTED CIRCUITS i . . 22
PARTS LAYOUT ......................... 23
SELECTOR SWITCH CHART ........... 24

PRINTED-CIRCUIT SHEETS ......... 25, 26, 27, 28, 29, 30
PARTS LIST.... .. 31, 32, 33,34, 35, 36, 37
COLOR CODE .................................. 38

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GENERAL SECTION

If the amplifier is otherwise operating satisfactorily,
the more common causes of trouble may generally

be attributed to the following:

1. Incorrect connections or loose terminal contacts.
Check the speakers, record player, tape recorder,

antenna and line cord.

2. Improper operation. Before operating any audio

structions.

3. Improper location of audio components.

The

proper positioning of components, such as speakers

and turntable, is vital to stereo.
4. Defective audio components.

Following are some other common causes of mal-

component, be sure to read the manufacturers in-

function and what to do about them:

PROBABLE CAUSE

l
PROGRAM 3 SYMPTOM l WHAT TO DO
AM, FM or_ I A. Constant or inter- l * Discharge or oscillation * Attach a noise limiter to the
MPX reception mittent noise heard at I caused by electrical appli- electrical appliance that causes the
certain times or in all ances, such as fluorescent noise, or attach it to the power
certain area. I lamps, TV sets, D.C. mo- source of the amplifier.
tors, rectifier and oscillator * Install an outdoor antenna and
* Natural phenomena, such ground the amplifier to raise the
as atmospheric static,, and signalrto-noise ratio.
thunderstorms. . * Reverse the power cord plug-
* Insufficient antenna input receptacle connections.
clue to reinforced concrete * 1f the n . ur t a certain
walls or long distance from f cise ocg 5 a
the station requencyn attac a wave trap to
the ANT. input
* Wave interference from * Pl ce the set 1' th r ele _
l other electrical appliances _a - away mm o e C
trical appliances.
B. Needle of the tuning * Needle movement is not I * Tune the set for maximum signal
meter oes no move necessari y re a e o e ' strengt .
l d t 1 l t d c th 11
sharply. sensitivity of the amplifier.
C. Zero point of the meter * Regional difference in field * The unit is not at fault.
moves greatly. intensity.
I
AM reception A. Noise heard at a * Natural AM reception * Install an antenna for maximum

particular time of day,
in a certain area or
over part of the dial.

B. High-frequency noise

FM reception Noisy

phenomenon .

* Adjacentrchannel interfer-
ence or beat interference

* TV set is too close to the
audio system

* Poor noise limiter effect
or too low S/N ratio due
to insufficient antenna in-
put.

NOTE: FM reception is affected considerably by
the conditions of the transmitting stations power
and antenna efficiency. Asa result, you may
receive one station quite well while having
difficulty receiving another station.

antenna efficiency. See ANTENV
NA" in the Operating Instructions.

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

* Although such noise cannot be
eliminated by the amplifier, it is
advisable to turn the TREBLE
control from midpoint to left and
switch on the HIGH FILTER.

* Place the TV set away from the
audio system.

* Adjust the antenna provided for
maximum signal strength.

* If this is not effective, use an out-
door antenna designed exclusively
for FM. When you use a TV
antenna for both TV and FM with
a divider, make sure TV reception
is not affected.

* An excessively long antenna may
cause [10158.