Matt circuit

This is a driver circuit for siren. This circuit usually used for car alarms. To build this circuit, we use VD-MOS FETs. This circuit receives 12 v supply from battery. A microprocessor sends complementary pulse waveforms to the driver circuit as inputs. Here is the circuit : This circuit uses two PHC21025 which each of them contains two FETs. Two BSN20 VD-MOS FETs in small SOT23 packages also used in this circuit. The maximum configuration of this circuit needs eight components and the minimum configuration of this circuit needs six components

This is the simple ic based Siren Alarm Circuit Diagram.  This siren alarm circuit may provide the final building block in an alarm circuit using a relay to activate it. This siren circuit is very simple and is constructed using common electronic components .  Siren Alarm Circuit Diagram When the switch is pressed C3 charges up through R4 with a time constant of 0.47 seconds and when the switch is released C3 begins a slower discharge through R7 and R3 with a time constant of about 5 seconds. The op amp 358 used in this project is set up as a voltage controlled oscillator. When the output of the oscillator (pin 7) switches low there is a charge remaining in C1 which holds pin 5 below the switching point. Current through R7 is proportional to the control voltage on C3. This current discharges C1 causing the voltage on pin 5 to rise towards the switching point at a rate proportional to the voltage on C3. When the switching point is reached pin 7 switches high and initially pulls...

This simple Toy Siren circuit for hobbyist and student who game liker, this is a very simple Toy Siren circuit,  This Toy Siren circuit can be built small enough to frt inside a toy. The Toy Siren circuit consists of a relaxation oscillator utilizing one uni-junction transistor (2N2646, MU10, TIS43). R2 and C2 determine the frequency of the tone.   Simple Toy Siren Circuit Diagram Pushing the button, SW1 charges up the capacitor and the potential at the junction of R2 and C2 rises, causing an upswing in the frequency of oscillation. On releasing the push-button the charge on C2 will drop slowly with a proportional reduction in the frequency of oscillation. Manual operation of the button at intervals of approximately 2 seconds will produce a siren sound. Sourced By: Circuitsstream