An Electronic Switch for a Physiograph
by David A. Larrabee
Biology has an old physiograph, whose basic amplifiers were tubes. A masters thesis required that a switch be opened or closed based on the position of a muscle. This information was being recorded on the physiograph. Rather than develop an external switch we built a device that monitored any channel of the physiograph and changed the position of a relay depending on the output level of the physiograph (level is user selectable). To guard against multiple transitions the device had built in (selectable) hysterisis as well as a 4 pole Bessel filter with a cut off frequency of 200 Hz.
The device performed satisfactorily, and the graduate student (I'm glad to say) got her Masters.
This is the kind of interdepartmental cooperation that I find so satisfying at ESU.
Or Perhaps you like the back.
Interested in the circuit? Give me a ring (Email etc..)
This Page maintained by Prof. Larrabee ( Larrabee@esu.edu )