Sansui FR Q5 Service Manual

Page 1

SERVICE MANUAL

COMPUTERIZED FULL AUTOMATIC

DIRECT DRIVE TURNTABLE

SANS!" Hi -05

SANSUI ELECTRIC (30., LTD.

SPECIFICATIONS

Type ........... Two-speed direct-driven

Speeds .......... 33-1/3, 45 rpm
Platter .......... Aluminum alloy die-cast

300 mm (11- 13/1 6") diameter, ,
1.3 kg (2. 86 lbs)
Motor .......... DC Brushless servo-type
(Quartz-servo) .
Wow and flutter . . Less than 0.025 % (WRMS)
Less than 0.018 % (WRMS-read
I out direct at the PG output)
S/N .......... Better than 62 dB (lEC-B)

Rumble ....... Better than 75 dB (DlN-B)
Tonearm ......... Statically-balanced
' S-shaped tubular type.
Tonearm length . . . 220 mm (8-11/16)
Overhang ...... 17. 5 mm (3/ )

Optimum cartridge weight
When the headshell supplied Is employed
........... 4 ~ 10 g
Dimensions ....... 440 mm (17-11/32) W
133 mm (51/4") H
I 385mm (155/32")D
Weight . . I. . . ..... 5.9 kg (15.1 lbs) net
8.1 kg (17.9 Ibs).packed
Potver consumption . . 10 W (rated)

0 The power voltage is adjusted to the one of the area where
you bought the unit. I

Specifications of the cartridge (applicable only to the
units with cartridge)

Modei SC-50

Type ........... Induced magnet
Frequency response . . 10 '3 20,000 Hz
Output voltage ..... 3 mV per channel

(1,000 Hz, 35.4 mm/sec)
Load impedance . . . . 47 kn I
Tracking force . . . . . 2.5 g
Stylus .......... 0.6 mil, diamond spherical (SN -50)

* Design and specifications subject to change without notice
for Improvements. . -

* In order to simplify the explanation illustrations may some-
times differ from the originals.

Page 2

1. BLOCK DIAGRAM

Screen
Plate Control Buttons Indication LED
START/STOP
(SW01) 0
Arm Lifter Arm Position REPEATiSWOZ) 0
sensor 33/45rpm Fin- W" "' 3
SelectoriswoaipJ- Flap 3 5
30/17cm W_ __ \" é" 30 17
Selector(SW04) 0_ Flop "-> '2' /
u
Pulse Detecting Head Waveform Shaping _> b REPEAT
Circuit '
Platter & um
Magnetic Pulse > E COMPUTER
Lifter Position-E ; -1
Sensor Micromotor fig
Driving Circuit K0 I
_ Lifter Cam Kl Q 0
uartz sc.
<- Strobo Plunger Solenoid 1
<- Drlvmg Circuit __> K2 E E; 3.633:
I -
l
DD Motor
lr
Strobo
Driving Circuit 19 11
8-0036 Diff Amp
DD Motor ' :I
. . . e __< 5 Ic12 cx-193
Drlvmg Circuit Servo Control It:
i______ .
Brake Circuit K- 6 g 17
Start/Stop : r
Control Circuit
leitter Amp
L J

2. OPERATION

2-1. General (See Block Diagram)

This model incorporates a DD motor control system composed of a
quartz-servo circuit, an electronic braking circuit, start-stop control
circuit, and etc. in addition to the full automatic system controlled
by microcomputer similar to that of FR-D4.

The full automatic system - composed of the same Driving Mecha-
nism Ass'y for Tonearm and Arm Lifter (here after called driving
mechanism assy) and the same microcomputer as used in FR-D4
- works as in the same manner as FR-D4 that micro motor and
plunger Solenoid of driving mechanism assy are driven in accord-
ance with signals from arm position sensor composed of LED and
photo-transistor, that from lifter position sensor (micro switches),
and in accordance with the procedure programmed in the micro-
computer. i

As regards the movement of driving mechanism assy, function of
arm position sensor and lifter position sensor, and operation of
microcomputer and peripheral circuit, see the service manual of
FR-D4. The quartz-servo circuit employs servo-control unit IC

1

(CX-l93), where the pulse from detector of rotation speed is com-
pared with the speed reference pulse from crystal oscilator to
control the rotation speed of platter. By means of detecting 960
magnetic signals recorded in coating on the interior surface of
platter by magnetic head (pulse detecting head), rotatior speed is
converted into electrical pulses proportionally (here after called
speed detecting pulse). Thus, the large number of the detecting
pulse compared with conventional one permit the highlyaccurate
servocontrol. The electronic braking circuit, consisting of mono-
stable multivibrator, makes DD motor generate counter-torque for a
certain term, in the case of both stopping turntable andchanging
speed selector 45rpm into 33rpm; thus, platter will be setstopped
or steady rotation in an instant.

Start-stop circuit - which controls the DD motor runningor stop-
ping in accordance with the signal from microcomputer -it0ps DD
motor when turntable rotates at twice the rated speed (or some
reason.