Origin Live Aurora MKI - Manual (Page 7)

7
Power LED
Rotary Speed
Control switch
view from front
view from rear
Motor Output Mains Input
A A
FIG A
S E T T I N G T H E M O T O R S P E E D
NOTE:
You will need to set the motor speed yourself. In the first 4 hours of use from starting up the motor, the speed
tends to drift but then settles down permanently. To burn in the regulator board components we recommend at
least 4 hours of running the motor before you accurately set the speed.
The thin output wires from the transformer only carry 8 volts and therefore safe to handle. Voltages inside the
transformer are dangerous so the transformer cas e should not be unscrewed or opened.
The switch box is designed such that when the rotary switch on the front of the control box is turned fully anti-
clockwise the motor is off. One click of the switch clockwise is 33.3 rpm and the second click clockwise is
45rpm.
NOTE: The speed can only be finally set or checked with the cartridge dragging on a centre track of a record as
the drag affects speed setting.
Instructions for reading the strobe
Place the strobe disc on the record to be played. Play the record and watch the relevant ring on the disc. Adjust
the speed until marks on the ring appear stationary while the record is rotating. It sometimes helps to stare at
infinity whilst doing this as the marks become easier to see. You can see the strobe effect in florescent light
although an ordinary bulb held about 2 feet from the strobe disc will also work fine. The bulb flickers at 50 Hz
in the EEC and 60 Hz in the USA.
You can purchase bayonet fitting florescent bulbs to fit normal lamps. Try to shut out daylight when carrying
out speed setting.
Set the speed
Adjust the motor speed as follows: using a small flat blade screwdriver turn the screws of the 25 turn resistors
P1 and P2 on the regulator board. These are accessible through the hole in the underside o f the control box (See
diagram below). P1 is for the 1
st
speed 33 rpm and P2 45 rpm. To increase speed, turn the presets clockwise.
until the speed changes. If the screw reaches the end of it’s travel you can usually hear a faint clicking.
The pre-set screw will not fall out and may need a fair number of turns to set the correct speed so keep turning
If this photo is not quite the same as your
control box you can identify P1 & P2 as
they are labelled on the circuit board.