Pillow school circuit-3

Models using this pillow calibration circuit include: Korean Samsung MC-15 movement, Venus C6418, V6458, Peony 64C1, Leroy CT6388W, etc.
The field sawtooth wave voltage is sent to the pillow calibration circuit through pin (4) of P404. R455, C454, and R457 form an integrating circuit to integrate the field sawtooth wave to form an upward convex parabolic wave voltage, which is added to B of the parabolic wave shaping amplifier tube Q451. pole, after amplification and shaping, a concave parabolic wave voltage of 9V (peak-to-peak value) is output from the C pole, and then added to The B pole of the composite tube composed of Q453 and Q452 is amplified and outputs a parabolic wave voltage of 12.5V (peak-to-peak value) from the C pole of Q452. Finally, it is sent to the row scanning circuit through the (3) pin of FR459 and P403. Scan current modulation. Achieve the purpose of correcting pincushion distortion.
VR451 is the line width adjustment potentiometer, and VR452 is the pincushion distortion adjustment potentiometer.