NotTaR of Television Sets : Vertical foldover                       
 Copyright © 1994-2007, Samuel M. Goldwasser. All Rights Reserved. Reproduction of this document in whole or in part is permitted if both of the following conditions are satisfied: 1. This notice is included in its entirety at the beginning. 2. There is no charge except to cover the costs of copying. I may be contacted via the Sci.Electronics.Repair FAQ (www.repairfaq.org) Email Links Page.

     << Horizontal output transis.. |  Index  | Comments on vertical prob.. >>

Vertical foldover

The picture is squashed vertically and a part of it may be flipped over and distorted.

This usually indicates a fault in the vertical output circuit. If it uses an IC for this, then the chip could be bad. It could also be a bad capacitor or other component in this circuit. It is probably caused by a fault in the flyback portion of the vertical deflection circuit - a charge pump that generates a high voltage spike to return the beam to the top of the screen.

Test components in the vertical output stage or substitute for good ones.