AN ULTRASONIC RECEIVER FOR DETECTING SIGNALS OF BATS
Abstract
A portable ultrasonic receiver was designed for detecting the signals of bats and other fauna which may emit ultrasonic sounds. The receiver has a passband extending from 15 kc to 200 kc, but bandwidth selection within this interval can be obtained with the use of plug-in filters. It has a small-signal voltage gain of 78 db preceding a rectifier which envelope-detects the ultrasonic signal. Following detection is 10 db of audio voltage gain. Additional gain is provided by a preamplifier inserted between the microphone and ultrasonic amplifier. All of the power is supplied by five 1.35 volt mercury cells but D-cell flashlight batteries may be used when necessary. The total weight of the unit is 5 pounds. Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 05, 1961
- Accession Number
- AD0268702
Entities
People
- Anthony Bertolini
Organizations
- Massachusetts Institute of Technology