25-08-2017, 09:32 PM
26-08-2017, 03:54 PM
This is police siren circuit using 555 IC
The work of the circuit IC1 that it constructs is a multiple astable vibrating circuit. Low-frequency signal of the output signal comes from the pin form 3 have about 1 Hz per frequency value that s were set by the value, R1, R2, C1 frequency signal will have to come out pinch 3 ways it built itself Carry well with the change of IC2R5. By the frequency of IC1 it will touch the total with the frequency in IC2 it will set valuable over 440 Hz - 550 Hz the frequency had to be sent out out 3 ways.
To be gush up from IC2 the connection is going to get along with B from Q1 to expand the tendency comes to sing bail make the sound of the circuit coming out looks like the sound of the police siren.
![[Image: Police-sirens-sound-with-ic-5551-600x355.jpg]](http://www.eleccircuit.com/wp-content/uploads/2010/07/Police-sirens-sound-with-ic-5551-600x355.jpg)
The work of the circuit IC1 that it constructs is a multiple astable vibrating circuit. Low-frequency signal of the output signal comes from the pin form 3 have about 1 Hz per frequency value that s were set by the value, R1, R2, C1 frequency signal will have to come out pinch 3 ways it built itself Carry well with the change of IC2R5. By the frequency of IC1 it will touch the total with the frequency in IC2 it will set valuable over 440 Hz - 550 Hz the frequency had to be sent out out 3 ways.
To be gush up from IC2 the connection is going to get along with B from Q1 to expand the tendency comes to sing bail make the sound of the circuit coming out looks like the sound of the police siren.