I'm new to the Apple II computers and am trying to get an Apple II Plus working with either a Viewmax 80 card or a Videx Videoterm card. (I don't have any manuals for either card.)
With the Viewmax 80 installed, I still get 40 columns, no cahnge in the video. There are a couple of jumpers on the card.
The Videx may be defective, because when I install it, I get nothing from the video output. I also get no 'beep' when the computer powers up. If I hook the monitor instead to the 40 column video output, all I see is the screen full of random characters (that you normally get for an instant when the Apple is powered up). They remain on the screen and there is no response from the keyboard. When I remove the Videx card the Apple boots normally.