Posts: 209
Threads: 12
Joined: Jan 1970
They're the io-port interface chips for the 1800 series. They are for attaching other computers, parallel printers or sometimes keyboards... stuff like that. Probably the reason you have TWO is because, in a terminal device based on the 1802, you would usually have one 1852 dedicated to input, and one just for output.
They're good to have... and yes, they ARE rather pretty.
*** Now, if you also happen to have a CDP 1861 lying around, its an essential for building the PIXIE display unit that accompanied the ELF microtrainer based on the 1802, and I've had trouble finding one without disassembling other equipment I want to keep whole (in other words, email me if you have one to sell!). ;-) ***