Thursday, November 26, 2015

12V Motorcycle Siren Circuit

Sirine Touring
Motorcycle Ilustration
Siren circuit works with a 12 volt Motorcyle alarm or warning alarm systems on road suitable for applications in integrated circuit UM3561 can give 0.2W power transistors integrated with BC547 and IRF9540 power output 10w made ​​to give enhanced

Rangkaian sirine Touring

Good Luck for siren circuit 

siren circuit

Sunday, November 15, 2015

Laser Beam Security Sensor

Little Laser Trip Wire circuit presented here can detect movement of people or objects while passing through the laser beam and trigger security alarms as alert signals to those concerned. What is behind this little laser trip wire is actually a red laser line that triggers a latch-switch when tripped. Here it is created by a single laser beam, a small light sensor brick, and a series of optional reflectors/mirrors.

In this article you will learn how to build a laser trip wire out of inexpensive electronic components, and you will build two circuits – the laser beam sender circuit and the laser beam receiver circuit. The receiver circuit includes an electromagnetic relay to assist the switching process of external electric loads such as floodlights, home alarm systems, etc.

Laser Beam Sender Circuit
laser sensor

laser sensor circuit

At the heart of the laser beam sender is a standard 650nM red laser diode having 5mW of power. The laser diode is fired by a 5 V dc supply with the help of two supporting components D1 (1N4007) and R1 (62R). Although the author used a “modified” laser diode lifted from his cheap laser pointer, you can use any (suitable) readymade laser diode module/card available from reputed online/offline components vendors.

laser diode used by the author
(laser diode used by the author)
laser beam sender circuit
(laser beam sender circuit diagram)
Laser Beam Receiver Circuit

Forepart of this circuit section is a 5mm photoresistor (LDR).This component is used to trigger the relay latch circuit wired around the planar passivated, very sensitive gate silicon controlled rectifier BT169 (T1). The 1N4007 diode (D2) connected in antiparallel with the electromagnetic relay (RL1) functions as an “orthodox” flywheel diode to protect the electronics from damage due to the back-emf pulse generated in the relay coil’s inductance when T1 turns off. Note that the relay should energized (and latched) when the laser beam does not shine on the photoresistor. You can use the power/reset switch (S1) to activate/deactivate your laser trip wire.

laser beam receiver circuit
(laser beam receiver circuit diagram)
Setting Up the Laser Trip Wire

If you are planning on protecting your staircase with the laser tripwire, then it is better to set it up as shown in the following example. First of all, try to place the sender and receiver units at the top of the stairs with a slight distance between them. Next, point the laser beam from the sender on a reflector placed at the bottom of the stairs and align it with the light sensor of the receiver. On the other hand, if you want to protect a wide-zone, then it is more estimable to use a series of reflectors/mirrors with your laser trip wire system!

laser trip wire setup

Monday, November 09, 2015

Schematic of Mini Emergency Light Circuit based LDR

Schematic of Mini Emergency Light Circuit based LDR. This is an LDR based emergency light that turns on a high watt White LED when there is darkness in the room. It can be used as a simple emergency lamp in the child’s room to avoid the panic situation in the event a sudden power failure.
It gives ample light in the room.

The circuit is too simple so that it can be enclosed in a small box. A 12 volt miniature battery is used to power the circuit. Two transistors T1 and T2 are used as electronic switches to turn on / off the white LED. When there is sufficient light in the room, LDR conducts so that the base of the PNP transistor T1becomes high and it remains off. T2 also remains off since its base is grounded. In this state, White LED remains off. When the light falling on the LDR decreases, it cease to conduct and T1 forward bias providing base current to T2. It then turns on and White LED switches on.

Schematic of Mini Emergency Light Circuit

Schematic of Mini Emergency Light Circuit based LDR

White LED used in the circuit is 1 watt High bright Luxeon LED. Since 1 watt White LED consumes around 300 milli ampere current, it is better to switch off the lamp after few minutes to conserve battery power.