Hello. I am newly to join this forum.
I have Apple II plus (Rev.4) which I bought I was high school student(38 years ago!).
I kept it for a long time and draw out to share the excellent machine with my son.
First of all, I cleaned the motherboard then reseated ICs and replaced power supply. Now it seems working (system boot, power light on, beep, reading Disk II, reset), but no video. No video, I mean the screen is flashing about 2 times per one second but no message. As I write above system is working, so I can enter command by keyboard in the blind and apple II+ responses good (if I input error command, apple warns with beep sound). My display is LCD I have confirmed that another working Apple II (RFI board) displays. So I think something is wrong with the video circuit.
Please give me suggestions, comments to find out the problem to check and solve them.
It is hard to express my thoughts and the situation in detail in English, but I will make efforts. If there is something that is hard to understand in my text or more information, please let me know.