Pincushion Correction Circuit-Discrete Circuit Diagram

Published:2011/5/4 8:17:00 Author:Robert | Keyword: Pincushion Correction, Discrete | From:SeekIC

It is the parabolic wave signal addedon the r520, and the user can adjust the parabolic wave signal amplitude by adjusting the r520, which canadjust the pincushion correction value as well. It is DC voltage added on the r523, and the user can adjust the line width by adjusting r523. This second circuit extracted from the Venus d2918 type pincushion correction circuit, whichhasjust V951 and v950 two-stage amplification more than the firstpincushion correction circuit shown below. The reason is that the field sawtooth wave is not taken from field deflection coilssampling resistor, but from tda8838's 46 foot, so thatit'sadded a two-stage amplification due to its small magnitude. The models which use this pincushion correction circuit have: Korea Samsung mc-15 module, Venus c6418, v6458, Peony 64c1, Lehua ct6388w and so on. The field sawtooth wave voltage is send to the pincushion correction circuit from the p404's 4 foot, and the r455, c454, r457 make up the integral circuit to integrate the field swatooth wave and produce the up-convexparabolic wave voltage. This voltage then is added on the b polar of the parabolic wave shaping and amplifying tube. Afteramplifying and shaping the c polar output 9V (peak-peak value) down-convex parabolic wave voltage. Then after the level width adjustment, left-rightpincushion distortion adjustment network made up by the vr451, vr452, r464, r463, r462, this voltage wave is added to the polar of the compound tube made up by q453 and q452. After amplifying the q452's c polar outputs 12.5V (peak-peak value) parabolic wave voltage. At last this voltage wave is send to the line scan circuit from fr459 and p403's 3 foot to modulate the line scan current. So this process achieve the goal of pincushion distortioncorrection. The vr451 is theline width adjustment potentiometer, thevr452 is pincushion distortion correction potentiometer.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Basic_Circuit/Analog_Circuit/Pincushion_Correction_Circuit_Discrete_Circuit_Diagram.html

Print this Page | Comments | Reading(3)