SME 20/3 User Manual

3. DIMENSIONS
Width 440.0mm (17.32”)
Depth 350.0mm (13.78”)
Height 173.5mm (6.83”)
Platter Diameter 325.0mm (12.80”)
Spindle to Arm 215.4mm (8.48”)
Net Weight 31.0Kg
Shipping weight 45.0Kg
4. SPECIFICATION
The turntable is driven by a 3-phase, 6 pulse, inductance motor, with 8 pole Neodymium
magnets and 3 integrated Hall position sensors.
The electronic controller uses a high performance microcomputer, optimised for motor
control. The Hall position sensors on the motor provide accurate feedback to the micro
controller allowing very accurate and stable speed control, including 33 1/3, 45 and 78
rpm. The reference oscillator is a 10MHz quartz crystal, which is multiplied by 4 to
produce an internal microprocessor clock speed of 40MHz.
The driver stage has CMOS buffers/MOSFET drivers with 1.2 Amp peak drive
capability.
The power output
stage is six high power complimentary Mosfets in a 3 Phase Bridge
Driver configuration.
Closed loop speed control is implemented using a pseudo sine wave commutation
sequence and a proportional-plus-integral (PI) algorithm.
The design incorporates a 4 layer surface mount technology pcb with on-board user
adjustable speed variation control.
5. SPEED RANGES
33 1/3, 45 and 78 rpm.
6

SME 20/3 Specifications

General

Brand	SME
Model	20/3
Category	Turntable
Language	English