Dennis,
It hasn't got all the answers yet, but we'll get it there. I'm considering what should be added to the 500-series plug-in interface page. You shouldn't have to dig through schematics and principles of operation to get an answer for what the multi-trace sync signal is (even if the name is terribly suggestive).
Too bad we don't seem to have a document similar to the 7000-Series Plug-in/Mainframe Interface Manual for the 500-series. I realize that it's a vastly simpler interface, but just a little more explanation would be nice.
I still need to add the pictures I took of those small curve tracer adapters.
-- Jeff Dutky
