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SL-B202

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SL-B202

Postby doublecee » 20 May 2018 15:19

Hi

One of my customers brought in an old Technics B202 to my record store for some advice. Firing it up, it was clear the motor was shot. Very grindy and rough sounding. I’m keen to know if anyone has a spare motor or can recommend someone in the UK who can overhaul the motor.

The turntable has sentimental value as it was his late fathers so a new turntable is not an option.

Many thanks
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Re: SL-B202

Postby Tom_Technics » 22 May 2018 00:50

Take the motor out and apart have a look at it, sounds like something foreign is stuck in it. Technics turntable motors rarely fail, even the belt drive ones.
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Re: SL-B202

Postby Sleepwalker65 » 09 Jul 2018 00:45

If the motor is making a fluttering noise, there is a straightforward solution: remove the bottom of the turntable and then de-solder the motor from the circuit board. Next, pull off the rubber cover from the motor body. There are 4 little tabs that keep the plastic end cap on the motor. Bend these straight, then before you pull the end cap off, make a “U” out of a turntable small piece of 14 gauge copper wire, and insert it into the two oval holes in the motor end cap, giving it a counter-clockwise twist to disengage the brushes from the motor’s commutator. Next, put an index mark on the motor body and end cap, so you put it back the right way around. Otherwise the motor will spin backwards. You can now carefully pry the end cap from the motor body. This will expose the inside of the motor. On the inside of the end cap is a bearing that should receive a drop of 3-in-1 oil. You will notice the motor’s armature can be extended so there’s a larger gap between the pulley and the motor body. Do this and apply a couple drops of oil to the shaft to lubricate the top bearing. Next, look at the opposite end of the motor, and you will notice a flat, washer shaped magnet (used by the hall sensor in the servo system) mounted to a light green plastic carrier. The sides of this carrier usually crack and flap against the inside of the motor body as the armature spins, producing a fluttering noise. You can remove these pieces and then glue the servo magnet in place with several drops of cyanoacrylate glue. These measures will quieten down the motor to near-silent operation if the bearings haven’t been run dry for too long. Re-assemble the end cap using the index mark to align it correctly. After resoldering the motor to the board, clean the two trim-pots and the front panel’s speed control pot with De-Oxit. You may replace the 330uF 16 volt electrolytic capacitor with a 470uF 25 volt cap, and the 10uF 16 volt electrolytic capacitor with a 10uF 25 volt cap just as good measure, as these are some 35 years old, and may be past their prime. A couple drops of Technics spindle oil will keep the platter spindle bearing running smoothly. As always, the original Panasonic belt (part # SJY90080-3) is your best bet to ensure good operation.
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