[1] The 1009 used the Synchronous transmit-receive (STR) protocol to transfer data at 150 characters per second (cps)[2]: p.577 over a single point-to-point dial or leased telephone line.
The system was advertised as being able to "link the magnetic core memories of IBM 1401 computers over telephone lines.
"[1][3] The 1009 attached to IBM 1400 series computers such as the 1401[4] In 1961 the transmission rate was doubled to 300 cps.
[2] In 1962 the 1009 was part of a test of data communications using the Telstar satellite to link two 1401 computer systems.
This computer hardware article is a stub.