Position: Index > Sensor Circuit >

Fire_siren

2014-11-04 15:06  
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.


Fire_siren
This LM3909 circuit produces a rapidly rising wail upon pressing the button, and a slower coasting down sound upon release. If it is desirable to have the tone stop sometime after the button is released, an 18-kΩ resistor can be placed between pins 8 and 6 of the LM3909. The sound is then much like that of a motor-driven siren, National Semiconductor Linear Applications Handbook, 1991 p. 402.