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PHILIPS 210 SERIES
There’s an odd sound fault on this set. After switching on,
the sound comes on at full volume, with a trace of hum,
even with the volume control at minimum. After about half
an hour however the conditions stabilise and the volume
control operates normally.
The volume control is returned to chassis via a 2.5µF
electrolytic capacitor (C1503). Either the volume control
itself is defective, the capacitor is defective or improperly
connected, or the earthing is not being made to chassis.
Note that the positive side of C1503 goes to chassis, the
negative side to the volume control.