Time Expansion Bat Detector Circuit
Time expansion te detectors are broadband detectors i e.
Time expansion bat detector circuit. Typically the sampling rate ratios can be varied from 1 10 to 1 32. Time expansion bat detectors. Bat detector choices are influenced by factors such as your experience the mode of operation that you want e g. Time expansion te detectors work by digitising the bat calls at a high sampling rate using an analog to digital converter and storing the digitised signal in an on board memory.
Te detectors are real time devices in that they can be monitored at the time of recording but there is an inevitable delay while the high speed sampled extract is. Chris eve s bat detector circuit view experiment. A bat detector is an electronic listening device that will allow us to hear the bat chirps and buzzes. A time expansion detector needs some kind of memory to store the bat call.
The output is audible on a loudspeaker or headphones. Hand held or passive and type of technology heterodyne fixed frequency time expansion or full spectrum. There are several types of bat detectors being used by bat listeners. Heterodyne detectors are great for beginners but professional bat workers will also turn to the more technologically advanced models which allow extensive recording and.
Time expansion te detectors work by digitising the bat calls at a high sampling rate and replaying them at a lower sampling rate immediately afterwards. Bat sounds are heard at 1 10th the frequency and 10 times the duration so no frequency information is lost as is the case with heterodyning or frequency division. Frequency divider heterodyne time expansion dsp digital signal processor. The advantage of this system is that all frequency information is retained for later analysis.
A 5 ms bat call at 40 khz would sound like a 50 ms call at 4 khz.