To hijack this thread... While sorting out some more stuff here I found an Atlantic Research protocol analyser. The front cover says it's a model 3600, but some of the PCBs say 4500 on them. Since from what little is on-line the 3600 could be upgraded to a 4500, I wonder if that is what happened to mine.
Anyway, it needs a lot of work. It looks like it was dropped from a great height. The plastic case covers are cracked. The chassis is twisted. It will need a new CRT. The cartridge tape drive is in many pieces. But the PCBs all look intact and it seems like an interesting challenge to get t to run again. I don't suppose anyone has the manuals for it.... -tony