Heterodyne Bat Detector Schematic

Build a semiprofessional bat detector with the teensy 3 6 microcontroller teensy audio board for less than 100 i developed this bat detector in the hope that it will promote the study of bat calls by everyone who is interested in the natural history and bioacoustics of bats and or interested in the technical details of how the detection.

Heterodyne bat detector schematic.

A bat detector is a device used to detect the presence of bats by converting their echolocation ultrasound signals as they are emitted by the bats to audible frequencies usually about 120 hz to 15 khz. This bat detector is a heterodyne design. A heterodyne function is often also built into the other types of detector. Click image for a larger jpeg view.

This project is about building a so called bat detector i e. A heterodyne bat detector simply shifts all the ultrasound frequencies downwards by a fixed amount so we can hear them. This was first presented by popular electronics magazine as an ultrasound detector in 1994. Hand held or passive and type of technology heterodyne fixed frequency time expansion or full spectrum.

It has been optimised for the use of an electret microphone. There are other types of detectors which record bat calls so that they can be analysed afterward but these are more commonly referred to by their particular function. From popular electronics 1994 the circuit shown here is for a heterodyne bat detector. This is a schematic for a straightforward direct conversion heterodyne detector having a tuning range of about 10 khz to 120 khz.

Nevertheless the sounds heard with this detector are highly informative with real scientific value. The current consumption is very low at only 8 ma which allows it to operate for about 100 hours with a set of rechargeable batteries. As you probably know bats emit ultrasonic sounds for the purpose of echolocation. Schematic of a heterodyne bat detector.

The by far most popular method for bat detectors appears to be the heterodyne down converting if you judge by the number of commercial and home built circuits frequency compression or time lapse this is the most advanced technology based on digital signal processing of the sampled bat sounds but it also requires the most advanced electronics. A bat detector uses a special microphone to capture these high frequency. A device that lets you listen to and record the sounds emitted by bats. Bat detector choices are influenced by factors such as your experience the mode of operation that you want e g.

Heterodyne detectors are the most commonly used and most self build detectors are of this type. Heterodyne detectors are great for beginners but professional bat workers will also turn to the more technologically advanced models which allow extensive recording and.