I recently purchased an Apple ][ Plus system. I have wanted one for a long time and finally saw one for a a decent price, knowing it had some issues. In the listing the seller said he couldn’t get it to display a stable image on a screen at all.
When I received it was able to get a almost perfect image on the screen besides several $ symbols that seemed to be stuck where they were. Functionally I was able to write / run some BASIC programs and it seemed to work okay. A nice included item was a vision 80 column card which after reading the manual I was able to get working, while in 80 column mode there are no $ stuck and the machine seems to operate perfectly as far as I can tell. Waiting on a disk drive interface card to arrive to actually try to run some software. I tried removing both the language card and vision 80 card to see if the $ issue would go away , it did not. I’ve read through the forum a bit about reseating every chip, started doing a few but no changes. Is there a repair manual available I should be looking at? Just want a good place to start.