In this paper a hardware/software system is described which permits the use of the Radio Shack TRS-80 Model I as a tachistoscope in perceptual-cognitive research. Hardware requirements and configuration, problems in developing software routines to handle reaction and stimulus timing using the TRS-80, and the development of a routine for…

Provides instructions for interfacing a pH meter directly to an Apple II microcomputer without an analog-to-digital converter. Includes program listing (with enough remark statements to make it self-documenting) in Integer Basic to display the pH readings. (Author/JN)

Describes apparatus, computer program (for Apple II), and procedures used in an experiment to determine the velocity of sound in air. In addition, the experiment focuses on the attention required in calibrating equipment and the measuring of both long distances and very short time intervals. (JN)