Midwest Data Source makes a software package called Contact which will allow
connection into BTOS (you can connect as a Burroghs MT-983, TD-730, or an
ET-2000 terminal).
BTOS is an extension of CT*OS, and Contact supports the Burroghs B2X family
running BTOS. The package supports also supports file transfer.
To locate a vendor's address and phone numbers, use the vendor name as a
search string.