b. The master height control is accomplished by varying the emitter resistance of
the current source, Q7. The output of Q9 feeds the master sawtooth waveform to the
individual vertical deflection amplifier.
(1) This waveform would suffice to deflect, vertically, the three pickup tube
beams if differential error were not present.
(2) It remains, therefore, to add to the master sawtooth waveforms in three
individual channels, differential linearity and height correction.
NOTE: From this point forward only the red
deflection system will be discussed (fig 23A).
Figure 23A. Red vertical deflection amplifier, sch dia
c. Red differential height control is obtained by feeding a DC control
voltage through the camera cable and applying it to a capacitor which is discharged
at a vertical rate.
(1) The sawtooth signal which is developed can be negative or positive,
depending on the setting of the red height control at the registration module.
(2) This signal is then added to the red master sawtooth waveform,
thereby adding to or subtracting from the overall Red height control.