@▷ Police bicycle siren circuits | Diagram for Schematic

Police bicycle siren circuits

My son like to watch movies about the police catch the culprit. However is funny because I do not see in violence model.Some stories the police rided a bicycle to catch the culprit. And turned on very loud siren. (In the minds of children).
When I build a project on electronic sirens. So he request me to build a bicycle police sirens. Which I’m not sure about the sound, However at least his son will like it. By the circuits below.

This circuit is the sound generator super siren, for use be alarm signal get by live frequency generator circuit that use , op-amp circuit. The principle works to are while still no press switch S1 will still have no the loud sound comes out from a loudspeaker SP1. When do pressure switch S1 then liberate C3 do something charge full until while press switch S1 and discharge go out. When liberate switch S1 come in at R7. Which perform in something limit current come in at 3 Non inverting legs of IC1a. By IC1, D1, D2, C1, C2 and R5 build be sound generator signal circuit then export come to way pin 6 of IC1a come to reach at pin 3 (Noninverting) of IC1b. By have R1 and R2 build be Dectector circuit. For do fining level has signal then signal to come out the way pin 7 of IC1b which will have flowing through comes in at pin B of Q1 for do something bias give Q1(BC639) bias. When Q1(BC639) work then make SP1 make a noise loud come out and make a noise poor loud C3 discharge be finished SP1 then stop make a noise loud.

Op-amp siren sound using ic 741

Circuit Two Tone Alarm with IC LM3900

This be Two tone alarm use op-amp IC number LM3900 (Quad Amplifiers) perform produce the frequency square wave 2 level , be high frequency and low then mix the sound in the end danger beep that is appropriate it has can to link up a loudspeaker with ,using power mosfet then have better use transistor which complicated and not durable. This circuit convenients for power supply 9V to 12V sizes and 8 ohm 20watt size loudspeakers will by large-sized have a voice loud small-sized better.

Two Tone Alarm with IC LM3900

"Police bicycle siren circuits Search Tags"
Alarm system siren, Linear op-amp, LM324 op amp