Origin Live Resolution Classic MKI - Manual (Page 12)

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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 of 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. The pre-set screw will not
fall out and may need a fair number of turns to set the correct speed so keep turning until the speed changes. If the screw
reaches the end of it’s travel you can usually hear a faint clicking.
Set the switch on the control box to the first click i.e. 33 rpm setting.
Set P1 so that the platter turns at 33.3rpm. When setting the speed, place the arm on the centre track of a record so that
the cartridge is tracking the grooves this ensures that the drag of the cartridge is taken into account. Speed variations of
up to plus or minus 2% are quite common on decks and the dc motor is capable of plus or minus 0.1% accuracy. Use
the strobe disc provided to set the speed (full instructions are on the card).
However if you have problems using the
strobe card, then count the rpm using the following method. Counting the 33.3 revs per minute is best accomplished by
placing a small piece of sticky tape on the perimeter of the platter and then counting 100 revolutions. 33.3 rpm is exactly
100 revolutions completed in 3 minutes. To save time in the early stages it is easiest to count 50 revs in 1 minute 30
seconds (or 25 revs in 45 seconds) and save the 100 count for the final check.
Please note the following points when setting the speed. Firstly all the figures below are based on setting the speed on
the deck using the centre track and letting the deck play for a good 5 minutes beforehand with the stylus on the record so
that the whole system has settled down. The regulators seem to take about 5 minutes to warm up,
so speed is about
2mins 58 seconds for 100 revolutions when the system starts from cold. In other words it is 2/180 x 100 = 1 % fast
when started from cold.
Speed variation with the dc motor varies minutely depending on the track played and cut of
record.
Click the rotary switch to the 2nd click clockwise and set P2 so that the platter rotates at 45 or 78 rpm (if you wish) using
the same procedure as outlined above.
The dc motors are noisy to begin with and are never completely silent in comparison to a/c motors. This is thought to
be due to a different type of precious metal brush. Having said this they still sound a great deal better in performance
terms.
To assist "running in" you can turn the speed right up via the control box. The motor then runs at high speed.
Allow this for approx 4 hours. After the running in period reset the motor speed. The motor should then be run for
approx 3 days under load (i.e. turning the platter) to free it up from vibration and to “bed in” the bearings.
Like most turntable manufacturers we recommend that you leave the turntable running between changing records as this
reduces the belt wear that occurs with constant stopping and starting.
Notes on motor & speed setting
-Do not use the power supply for anything other than the dc motor or the power supply will definitely be irreparably
damaged and you could also damage the equipment you are plugging it into.
-The circuit will take around 8 hours to run in and sound it's best.
The speed stability of your deck should be excellent once everything has settled down in a listening session i.e.. The
power supply and switch box have been left plugged in on standby for 15 minutes, the platter has been turning for 2
minutes and the cartridge has been on the record for 30 seconds. Bear in mind that the ear detects when music is playing
slightly slow much more easily than it detects it playing fast. For this reason most manufacturers set their decks to run
slightly fast. You can expect a bit of speed variation when the motor is first switched on - it takes about 2 minutes to
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. Some boxes have the speed
adjusters on the rear of the box – in which case the
left hand screw is for 33rpm & the right hand screw
is for 45rpm (as you look at the rear face).