A simple computer-controlled analogue ramp generator for producing multiple ramp-and-hold stimuli.
This report describes an inexpensive ramp generator which produces multiple ramp-and-hold stimuli ("staircase-type" wave forms). The output voltage is analogue and is, therefore, free of stepping artifacts characteristic of digital function generators. When coupled with a standard power amplifier and mechanical vibrator, this system is particularly suitable for stimulation of mechanoreceptive sense organs. Connection to the serial port of an IBM personal computer, or the user port of a BBC computer allows complex ramp-and-hold sequences to be developed and repeated. The number, duration and sign of ramps, and the duration of intervening hold periods can be set using the computer. This system has been used successfully to characterise phasic and tonic neurones in the locust metathoracic femoral chordotonal organ (a leg position and movement detector).
Matheson
T
T
Department of Zoology, University of Canterbury, Christchurch, New Zealand.
Ditz
F
F
D000818:Animals; D003201:Computers; D004581:Electronics; D004594:Electrophysiology; D006110:Grasshoppers / Q000502:physiology; D008465:Mechanoreceptors / Q000502:physiology; D009474:Neurons / Q000502:physiology; D010812:Physical Stimulation / Q000295:instrumentation*; D012984:Software