Sansui SR 838 Service Manual

Page 1

SPECIFICATIONS

o SR-636
STEREO TURNTABLE Type ........ t . . 'l'wmspeed direct-driven
Speeds.......... 33-1/3,45rpm
Fins speed adjustment
- range ......... $2,596 .
Platter . . . , ..... . Aluminum alloy die-cast
318 mm (12-9/16) diameter,

1.6 kg (3.5 lbs.)

Motor ........ . . 20-pole brushless DC servo-type
Wow and flutter . . less. than 0.028% (W.R.M.S.)
SIN . . . ....... better than 63 dB {lEC-B)
Rumble . . . t . . i better than 71dB(D1N-B)

Tonsarm . . . ...... Staticaliy-baianccd

S-shaped tubular type
Toncarm 1engzh. . . 230 mm (SJ/16"]
Overhang ...... 16.1 mm (/16")

Optimum cartridge weight
When the headshell supplied is employed

..... . . I . . 4~ilg
Dimensions . . . . . . . 490mm (19-5116")W
167 mm (G's/8") H
390 mm (15-3/8") D
Weight .......... 12.8 kg(28.2 lbs) net
14.8 kg (32.6le) packed
Power Consumption . . 7W(rated)
Cartridge ........ SW43
Frequency response 10 ~20,000H1
Output voltage . . . 3.3 mV per channel (1 .000 Hz
50 mm/sec)
Load impedance . . 47 H1
Tracking force . . . 2.0g
Stylus ........ diamond (SN-43)
o SR-838
TYPE , A . . . . . . . . . Two-speed direct-driven
Speeds . .. ....... 33-1 (3,45 rpm
Fine speed adjustment
range ........ . 122.5%
Platter .......... Aluminum alioy die-cast

318 mm (12-9/16) diameter,
1.7 kg (3.7 lbs)
Motor .......... 20-13010 brushiess DC servo-type
(Quartz-servo)
Wow and flutter . . less than 0.025% (W.R.M.S.)

S/Nl . . ....... better than 64dB (lEC-B)
Rumhie ....... better than 72dB lDleB)
Tonearm ......... Staricaiiy-balanced
S-shaped tubular type
Tonearm length. s . 230 mm [9-1/16")
Overhang A . . . .. 16.1 mm (Ii/16")

Optimum cartridge weight
When the headshell supplied is employed
.......... 4 ~11 gill ~20.5gwitnthesub-
weight mounted)
Total weight 1nc1uding the headshell)
...... . .. 23~323 with the subwelght
mounted
Dimensions . ...... 490 mm (19-5/16") W
167 mm (66/8") H
390 mm (1 53/8") D
Weight . .. . l . . . .. 12.8kg (28,2lhs) net
14.8 kg (32.6 lbs) packed
Power Consumption . . 7W (rated)
Cartridge ........ SVv43
Frequency response 10 ~ 20,000 H1 .
Output voltage . . . 3.3 mV per channel (1 ,OOOHZ

SOmm/scc)
Load impedance . , 4T kfl
Tracking force . . . 2.05
Stylus ........ diamond (SN-43)

0 Design and specifications subject to change without
notice for improvements.

4-. 1

SANSUI ELECTRIC CO, LTD.

Page 2

1. BLOCK DIAGRAM

1) SR-636
Flg 1-1 II" - '1
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I MOTOR I
I : FG SERVO CIRCUIT
r- ------------------- -1 I- - - - - - - "I
I .
I SPEED I I SPEED PROPO- 55E IIIEENCY _, VOLTAGE I I CONTROL I
I SENSER I I TIONAL PULSE CONVERTER COMPARATOR I I CIRCUIT I
L. _______ J L _ _ _ _______________ _ __ _J
_ _ _ _. _CE ELL §EBILO_CIBC_ULT_ I I
II- 1, ' I ELECTRONIC I
IAOEMULTIPLI- PHASE . I BRAKE I
I CATION COMPARATOR I |_ ______ J
: I
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I CR GENERATOR I
I. _______________ J
MOTOR CONTROL CIRCUIT
Fig. 1-2 " """"""""""""""""""""""""""""" " g,I.I5.3 POSITION SENSERCOIL
M-I~LM3 DRIVING COIL
m BIAS COIL
FG SERVO CIRCUIT

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PLL SPEED SELECIOR SW

______________________________________________________ .1

flat

oSR-eae, SR-838 Main Circuit -' "

The electronic circuitly in this set is two servo circuits and a motor For this reason, this set employs both the F-G servo system and .
control circuit. PLL servo system by which rotation fluctuation is always locked
The servo circuit employs the PLL servo system and the speed ' in the reference signal.

control system (Frequency-Generator servo) together. PLL servo circuit of the phase control system, is both CR genera-
The F-G servo system is effective for the threshold characteristic tor and quartz generator used in this model.

and also control of PLL-Lock-out.
However, PLL servo system has an advantage against the Influence
by load fluctuation.