|
If it has a pot for vertical size, it would be as simple as adding a second pot and a switch to change which one is in circuit. You should try to design it so that it doesn't lose vertical deflection when when you switch it. For examplt, if lower resistance = a larger picture, then set it up so that the second pot is connected in parallel to expand the picture for full screen.
Be aware that there may be objectionable stuff visible in the VBI when the picture is compressed. Macrovision and other VBI data will probably show up. TVs with a 16:9 feature have to blank this.
|