Technics SL 15 Service Manual

Page 1

ORDER NO. SD8105190565

Service Manual

QUARTZ Direct Drive Automatic Turntable System

Service Manual.

,
*The colors of this model include silver and black.
*The black type model is provided with (K) in the

SI.- 15

[E],[EK],] [XL],[EG] JJEB]
[EF] [XA X] EH], [El]

SL-15(K)

E],[[EK], XL] [EG],
[EB], [E[F]: [XA], [XM], [EH]

Areas

* [E] is available in Switzerland and Scandinavia.

" [EK] is available in United Kingdom.

* [XL] is available in Australia.

" {E6} is available in F.R. Germany.

" [EB] is available in Belgium.

[EF] is available in France.

[XA] is available in Southeast Asia, Oceania, Africa,
Middle Near East and Central South America.

[XM] is available in Central South America.

[EH] is available in Holland.

[Ei] is available in ltaly.

Power supply:
Power consumption:

Dimensions:
(W x H x D)

Weight:

I Turntable section

Type:

~110-120/220-24O V, 50/60 Hz
DC 12 V (DC input jack)
20 W (AC)

5 W (DC)
315 x 8.8 x 31.5 cm
(12»1/2" x 3-1/2" x12A1/2")
With the cabinet too open to
maximum position: '
31.5 x 38.5 x 31.5 cm
(12-1/2" x 15-5/32" x 124/2")
6.6 kg (14.3 lb.)

Quartz-phase-locked control
direct-drive automatic turntable
Automatic operation
Programmable band selection
Repeat play
Program repeat
2-speed inward/outward search
Program skip
Program invband repeat
Auto start/Auto lead-in
Auto return
Auto stop
Auto speed select
Auto size select
Record presence detection

English
. . . . . . - . . .
SpeCIflcatlons Specmcations are subject to change without name for further Improvement.
WeIght and dimenslons shown are approxrmate.
enera rtve met : Irect rIve
G | D ' had 0' d '
Motor: Bruschless DC motor

Drive control method:
Turntable platter:

Turntable speeds:

Speed deviation:
Wow and flutter:

*This rating refers to turntable assembly alone, excluding effects
of record, cartridge or tonearm, but including platter.
Measured'by obtaining signal from built~in frequency fenerator
of motor assembly.

Rumble:

l Tonearm section

Type:

Effective-mass:

Tracking error angle:
Rasonanoe frequency: 12 Hz
Toneerm drive motor:

Quartzrphase-locked control
Aluminum diecast
Diameter 30 cm (12 inches)
33-1/3 rpm and 45 rpm
Auto speed select

(Manual selection possible)
Within i 0,002%

0.012% WR MS"

0.025% WRMS (JlS C5521)
d: 0.035% peak

(IEC 98A weighted)

-56 dB (IEC 98A Unweighted)
-78 dB (lEC 98A Weighted)

Dynamic balanced type
Linear tracking tonearm
4-pivot gimbal sUspension
9 9 (including cartridge)
Within 1 0.1D

Coreless DC motor

Technics

Matsushita Electric Trading 00., Ltd.
PO. Box 288. Central Osaka Japan

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Operation P.C.B.

Logic control P.C.B. l-i

Optical sensor
Tonearm

Arm drive wheel

Arm drive motor

Arm motor drive P.C.B.

I GENERAL

This is a high efficiency quartz DD player system provided with an automatic program selecting function, taking over the size
and functions of SL-iO [See (Note).] _

The automatic program selecting function is to detect the blank between specific bands on the record disc by the reflection
type optical sensor using infrared ray and to move the tonearm to the head of the band by the microcomputer. This detecting
sensor is built into the upper cabinet, but it is located away from the tonearm and cartridge positions, and is interlocked with
the tonearm operating mechanism to detect the number of bands and their positions. Thus, the detection system is very
unique.

Normal operation of this unit without touching the program keys brings about the same functions as those of SL-l 0. When
the program keys are touched, the tonearm once moves to the inner periphery of the record, while the reflection type otpical
sensor reads the number of bands and their positions on the record; then, pushing start key causes the tonearm to play the
programed bands in order.

For example, when the start key is pushed after setting the program keys 2, 5, 3, 1 and 4 in order, the 2nd, 5th, 3rd ist and
4th programs are played in order. During the play, the program LED blinks indicating the position of band being played.
Also, with it interlocked with the repeat key, the programs can be continuously played in the order of 2nd, 5th, 3rd, ist and
4th bands. When desired to repeat only the 3rd band, the purpose can be achieved by pushing the program key 3 and inter-
locking it with the repeat key. All the programs can be cleared by pushing the stop key. Before pressing the start key, the
selected program can be canceled by pushing the program key again. This player system is really full of enjoyment having
multiple functions such as skipping and selecting of the programs.

Note: Features of SL-10

1. Quartz DD compacted to record jacket size.

Set the record and push the start switch. After that, the player will control all the functions.

2. Linear tracking tonearm having highly accurate servo function based on optical sensor (optical non-contact detection).
Because of the dynamic balance tonearm of gimbal suspension structure, highly accurate tracking is attainable irrespective
of the player positions.

. The basic control is very simple, and in addition, it is of multi-function type that is favorably accepted by enthusiasts.

. The Technics unique single structure DD, incorporating the rotor of the motor into the turntable, and the entire peri-
phery detection FG are employed.

. Precision aluminum die-cast two-layer (upper and lower) cabinet.

Two-power source system, capable of using DC power.

. Strobe~attached stabilizer for holding the record.

. Adapter (45 rpm) built-in.

. Dial scale to check the tonearm position.

bl»)

(QQVQU!

0 Automatic program selection (See Fig. A)

The optical sensor unit in the upper cabinet is interlocked with the tonearm. The infrared ray radiated from the infrared
LED of the Sensor is cast on the record disc, and the reflected ray is received by the photo transistor. The reflection factor
is higher at the blank groove causing the amount of light entering the photo transistor to increase. At the sound groove, the
amount of light entering the photo transistor decreases due to diffused reflection.

The blank between bands is found by detecting the difference in reflection factor between the blank and sound grooves.
The reflected signal is then processed by the microcomputerto control the tonearm operation.

Infrared reflection
type optical sensor

Light emitting
element

(lnfarared LED.)

Light emitting element
(Photo transistor) 0

Record

Detecting the blank between bands Detecting the sound groove of record

Fig. A
:l
:I Reset
l: 3; detection
2 x Tonearm position detection
:1 E
:1 E
l:l 8
l:l a:
l:l
:1 Tonearm servo Drive Dynamic blance type
cueing start stop circuit linear tracking tonearm
' <1 <2 i> [>
El l:| MNMOEPD offset angle detection
Band detection
circuit
Keyboard Record size Cartridge
detection Reflected 2
signal
Infrared reflection
type optical sensor Turntable
33/AUTO/45 055,00,
drive circuit
Speed selector Muting

Block Diagram of SL-15
Audio output

Page 22

.Upper Cabinent

I EXPLODED VIEW.....