not sure whether this topic has been already discussed here....
I was wondering why I am struggling to get a picture when connecting my Newton Replica to any monitor or TV other than my monochrome Apple II monitor. I tried already many different kind of displays and composite video adapters but without success. Sometimes I get an on / off picture sometimes the selected display struggles to sync. More often there is no picture at all. I tried to adjust the adjustable resistor R12 in all directions — no luck.
But again — on my old Apple II monitor there is a crystal clear picture without no problem. Therefore I always thought this is related to this difficult non standard video out of our Apple—1.
Today I looked in this issue again and found something strange. In the schematic this adjustable resistor R12 is rated with 100 (Ohm?). Having this unit adjusted so I get a nice picture on my AII monitor I measure 1100 Ohms!
I received that part from another Apple—1 owner here in Germany and was told that's the right one. I am not so sure anymore. I can adjust that thing from 0 up to 1200 Ohms and just at the very end of that scale I am getting a picture on the selected display if any.
What is your opinion? Did I install the wrong type? What adjustable resistor types you are using?