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need ideas,suffestions and advices on this project: listening device for bird watching Answered

having the following specification:1.handheld,battery operated.2.frequency operation in audible frequency range.3.minimum of 30bB signal amplication.4.volume control for final outout stage.5.automatic gain control.6.10 second recording of sound,non volatile storade.7.two output sockets for headsets,5mm jack plug sockets.8.5 hour operational capabilities on one set of batteries.9.On/Off switch with LED indication.10.LEd to indicate recording.11.LED to indicate playback

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Re-design
Re-design

11 years ago

Look at this piece of equipment.
http://www.defensedevices.com/big-ear-parabolic-dish.html
THen either buy one (price is right) and modify it where it is lacking or build yourself one from scratch.

I don't think Radio shack carries one anymore. But they do carry lots of stuff you could use to build you own.

You could use an old satelite dish for the reflector as a starting point. Drill a hole in the middle for a length of threaded rod and put a high gain mike on the end of that so you could move it in and out to focus the sound. And pick a battery op. amp that has high enough gain ... and so on an so on.

good luck.

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abrinah
abrinah

Answer 11 years ago

i have to design that circuit.need its circuit,hardware n software.its my project project.