Whistle Responder

Beeps when hears your whistle A gadget suitable for key-holders, games etc. These devices contained a special purpose IC and therefore were not suited to home construction. The present circuit is designed around a general purpose hex-inverter CMos IC and, using miniature components and button clock-type batteries can be enclosed in a matchbox. It is primarily a gadget, but everyone will be able to find suitable applications.
Whistle Responder - schematic

This device beeps intermittently for about two seconds when a person in a range of around 10 meters emits a whistle. The first two inverters contained in IC1 are used as audio amplifiers. IC1A amplifies consistently the signal picked-up by the small elec

Leave Comment

characters left:

Ibi   Feb 21, 2008

Can't make it work......mmm I've changed the Cmos, changed the bc337, buzzer(i have a 3.3KHz) Does anyone knows if it works?

New Circuits