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PHILIPS 210 CHASSIS
This set is fitted with a six press -button tuner which is
faulty. When the buttons are tuned they will not stay in,
coming out after rotation of the button. This happens only
when the buttons are tuned – each button can be pressed in
and locked until rotated.
It is most unusual for this type of tuner to be sufficiently
worn for any replacement parts to be required. Remove the
tuner and inspect the action. A spring holds in the retaining
plate for the push-button stems. See that the spring is active
and the plate positive. Clean and lightly oil all moving parts.
Check that the tuner cores can be turned through the tuning
range.