The Tektronix 240 is a pre-GPIB "Program Control Unit" introduced in 1968 for the Tektronix 230 and 568. It can be extended using the R250 so that it can control other instruments such as the R116 and R293.
The 240 can execute programs from an optional magnetic disk or paper tape.
- Tektronix 240 Manual (OCR, PDF)
- 240 and R250 Description from Tektronix Automated Testing Systems book (PDF)