d. Red differential vertical linearity control is achieved by first
generating a sawtooth waveform as is done in the red height control circuit.
(1) The remotely controlled sawtooth waveform, which is sent from the
CCU, is then applied to an integrator circuit which converts the sawtooth to a
negative or positive going parabola.
(2) The parabolic waveform is then added to the master sawtooth
waveform, thereby producing differential linearity correction.
e. The master sawtooth waveform with the added differential corrections
described this far are then applied to the vertical deflection amplifier module.
These amplifiers are basically differential input operational types which compare
the deflection current samples with the applied deflection waveforms.
(1) The loop gains of these amplifiers are such that precise tracking of
the reference and current sample waveforms is obtained.
amplifiers so that centering voltages are not dependent on the DC potential of the
f. Deflection failure protection is obtained by adding the three horizontal
foldout located at end of Lesson 3).
(1) All six of these input voltages are maintained at a constant peak to
peak voltage level and the protection circuitry is biased on and is passing the
correct amount of voltage to grid 2 (G2) of the pickup tube.
(2) If any of the six input voltages vary by 75 percent, the protection
circuitry will be biased off causing the voltage to C2 to be grounded; thus giving
G2 a 0 volt potential and stopping conduction within the pickup tube. This process
protects the target of the pickup tube; otherwise without deflection, the electron
beam would strike the target in one single area causing damage to the target.