There is an interesting pdf file (5_013.pdf) by Mark Walker in Microchip CD
that describes how with a PIC you can build a simple mosquito repellant that
mimics the 30Hz frequency of a dragon fly.

I remember to have read somewhere that an ultrasonic frequency (possibly in
the range of 25KHz to 40KHz), is quite effective in repelling mosquitoes.

I would appreciate any suggestions on the frequency required for the project
and other relevant details.

Thanks & Regards,

Bala

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