PHILIPS 21TG1000

The top of the picture is cramped and does not
fill the screen. Reducing the height control makes
the picture a little better but it still does . not fill
the screen by 3in, top and bottom. Increasing the
height, the picture fills the screen momentarily
then drops at the top by about tin. and is
cramped. -A. L. Brown (Bolton, Lancashire).
Check the h.t. feed to the field timebase
generator (via the width control). Check the
resistors and capacitors here and those connecting
to the boosted h.t. line. It would seem that a resistor is high in value but that initially the
supply to the oscillator is sufficient due to the
charging of a capacitor, the charge, of course,
quickly exhausting when the generator takes
current.