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Pioneer PL-250 turntable restoration

Pioneer PL-250 is direct drive auto-return turntable with the s-shaped tonearm. This turntable is manufactured by Pioneer in around 1979 - 1982.

The PL-250 which we got had many electronic and mechanical issues. The main electronic problem in this unit is it's varying speed. The speed controller of this turntable is based on PA2004 and PA2005 ICs. After checking each an every electronic component in speed controller PCB, we figure out that the problem is in the "Pitch Control" potentiometer (VR1) of this unit. After replacing VR1 with 5K (log) potentiometer, the speed problem got resolved and the motor starts to spin with correct speed(s).

Servo motor and speed control assembly of Pioneer PL-250 turntable.

The turntable which we got comes with original Pioneer cartridge with "broken" stylus. We test several cartridges with this player including cheap US $ 3.00 cartridges (which are available on eBay), Audio Technica AT-91 and Audio Technica AT-95E cartridges. Out of all these cartridges, cheap Chinese (US$ 3.00) cartridges produces worse results and the most noticeable thing with that cartridge is its heavy distortion in 1.0kHz - 6.8 kHz range. Both Audio Technica cartridges produce excellent results with this player.

After fixing all the issues this unit starts to work perfectly and produces excellent results. We mainly test this turntable with Pioneer SA-420 power amplifier system.
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