AN ECONOMICAL TIME STANDARD FOR CALIBRATING CARDIOTACHOMETERS AND BIOLOGIC DATA RECORDINGS.
Rept. for 10 Aug-1 Dec 65,
SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TEX
Pagination or Media Count:
A single-stage pulse-frequency divider is reported which will divide 60 pulsessec. by 60, yielding 1-second pulses with reliability from -40 to 80C. Division by 300, yielding pulses at 5-second intervals, is reliable from 5 to 45C. A triple-division circuit is then developed from the single-stage divider concepts. This circuit is incorporated into a calibration instrument which produces pulses in a frequency range useful for time calibration of biologic data. When the instrument is used as a cardiotachometer calibrator, pulses are available from 30 to 300 pulsesmin. as a time marker, periods range from 50 msec. to 10 sec. The circuitry remains stable over a line voltage fluctuation of plus or minus 20 and a temperature range of -15 to 80C. The output pulse, available as either a negative or positive going pulse, is 8.33 msec. wide, has an amplitude greater than 10 v., has rise and fall times of the order of 10 microsec., and exhibits a typical timing accuracy of plus or minus 0.02. Author
- Medical Facilities, Equipment and Supplies
- Electrical and Electronic Equipment
- Biomedical Instrumentation and Bioengineering