From marc989 at gmx.de Wed Sep 6 06:21:05 2006 From: marc989 at gmx.de (marc989@gmx.de) Date: Wed Sep 6 12:43:02 2006 Subject: [Ecophysiology] Bat-counter Message-ID: <20060906112105.93710@gmx.net> hello, I found a message of you in a Internetgroup and I?m very interesting in your methodes to count bats. I build also an bat counter with microcontroller and infra red gate to count the flight direction. Now, I try to recognize the ultrasonic calls, but it doesnt work good. I only use the frequency input of the microcontroller to calculate the frequency. I hope you can help me.... and you are not scared about my english. ;-)) best regards MARC -------------------------------------------------------------- Hello, its depend on species and vary on species to species. The pitch can be determined by spectrometer (Discret Fourier Transform and DSP is your friend:) ) or from the literature (for a concrete species). Microphone(wide bandwith)-->preamp-->A/D converter-->Puffer1 (RAM)-->Fast Fourier Transform -->Puffer2-->Human interface I am an electrical engineer and I have developed some instruments especially for bat research. If you are interested in , I have developed Infra Red Gate for Bat moving direction and Bat counter Datalogger with microclimate datalogger, and I can customize a solution for your project regarding ultrasound processing (recording time domain / frequency domain, spectra, etc.) . Best Regards, Attila -- Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! Ideal f?r Modem und ISDN: http://www.gmx.net/de/go/smartsurfer