I've recently purchased an Apple II Plus off eBay and it's in working order.
One thing I'd like to know is how much memory it has. It boots into Applesoft BASIC fine, so I'm assuming it has at least 4K of RAM.
Looking at the motherboard, I see all chip sockets in the RAM section are full, but I can't tell what kind of RAM chips they are (4K or 16K?) and I don't know for sure if they are working properly or not.
Is there a way to identify a RAM chip by the lettering on top?
Is there any built-in memory diagnostic in the monitor or in Applesoft BASIC?