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  • Radio, alarm clock and thermometer

    2016-02-19 02:18:4471

    Original project by: D’D?D°D′D???D?D°D2 D¨D°D?D?D2D°D?D?D2 Such multi-purpose device is a nice example of of using microcontroller for combine...

  • Strobe Alarm

    2016-02-19 01:46:5568

    This strobe gives a visual indication of a sensor input. The input signal causes Ul, a light dependent resistor, to chaijge CI and C3 through R4. When ...

  • Dc Supply Low voltage alarm

    2016-02-19 01:13:1571

    This low voltage circuit can be used to monitor batteries and other volatile sources of current for problems. The circuit sounds an alarm and lights an...

  • One second Audible Clock (CD4024)

    2016-02-19 01:04:3597

    Accurate, finger-operated portable unit Circuit diagram: Parts: R1______________10K 1/4W ResistorR2_______________4K7 1/4W ResistorR3_____________100R ...

  • gate alarm circuit (1N4148)

    2016-02-19 00:52:4568

    This article describes a gate alarm circuit (1N4148). The principle is very simple, very practical. The circuit components can help you understand bett...

  • Programmable Clock Oscillator

    2016-02-19 00:52:3666

    This is a voltage controller oscillator that was designed as a wide range oscillator to generate clock pulses for a stepper motor drive system. It does...

  • Low-battery-warning

    2016-02-19 00:45:2294

    A voltage divider consisting of Rl, R2, and R3 is used to set the input reference voltage below which the batteries are to be replaced. That reference ...

  • Warble tone alarm circuit

    2016-02-19 00:34:1469

    Warble tone isa tone whose frequency varies periodically several times per second over a small range; used to prevent standing-wave patterns from formi...

  • How to build A One-Time-Only Burglar Alarm

    2016-02-19 00:32:1566

    Description This alarm is designed to sound its Siren only once. That is - when the alarm is activated - the Siren will sound for a preset length of ti...

  • The Circuit Diagram of Fire Alarm (BC548)

    2016-02-19 00:14:31158

    This article describes The Circuit Diagram of Fire Alarm (BC548). The content is very simple, very helpful. Components in this article can help you und...

  • Motion detector alarm circuit

    2016-02-19 00:09:16104

    This motion detector alarm circuit can detect a moving person from a distance of 1 meter. It uses a Dual IR Transmitter-Receiver module HOA1405. When t...

  • 3 motorcycle alarm circuit

    2016-02-18 23:55:2277

    This article describes the three motorcycle alarm circuit. The circuit is very useful, it is worth Duokanjibian then master the principles of the theor...

  • Safer Security System Alarm circuit diagram

    2016-02-18 23:23:1567

    A Many security systems use a closed loop of wires and switches arranged so that whenever a door or window is opened, the loop will be broken and the a...

  • Hijack Alarm

    2016-02-18 23:13:5463

    Description The first circuit was designed for the situation where a hijacker forces the driver from the vehicle. If a door is opened while the ignitio...

  • Automatic Arming Auto Alarm

    2016-02-18 23:01:4164

    When the car is turned off when the circuit opens automatically. It not only gives you a variable time to go out and locked up, but also provides a var...

  • Real Time Clock Module - DS1302

    2016-02-18 22:43:1864

    Description This a custom designed module for the DS1302 Real Time Clock. Interfacing the DS1302 with a microprocessor is simplified by using synchrono...

  • Discrete Sliding Tone (Frequency Ramp) Doorbell

    2016-02-18 22:37:5463

    This doorbell circuit produces a low tone that will slide up to higher frequency. The equivalent total resistance connected between the base of Q1 and ...

  • Ultrasonic Burglar Alarm

    2016-02-18 22:35:4163

    Figure 1 Ultrasonic Burglar Alarm: Transmitter and receiver parts of the circuit are connected each other by using a triple cable. System operates with...

  • How to build A Cmos Based Motorcycle Alarm

    2016-02-18 22:33:5766

    Description This circuit features an intermittent siren output and automatic reset. It can be operated manually using a key-switch or a hidden switch; ...

  • Alarm System(1N4001)

    2016-02-18 22:33:2765

    This article briefly describes the Alarm System (1N4001). This principle is easy to understand, but also very practical. Depth understanding of circuit...

  • Door Alarm (BC547)

    2016-02-18 22:30:5169

    This article describes the Door Alarm (BC547). The principle is very simple, very practical. The circuit components can help you understand better gras...

  • Sun - Up Alarm

    2016-02-18 22:28:2664

    The Sun - Up Alarm can be used to provide a audible alarm for when the sun comes up or it can be used in a dark area and detect when a light comes on. ...

  • Small Loop Alarm Circuit Schematic Showing

    2016-02-18 22:26:2662

    This article is a small loop alarm circuit schematic presentation. The circuit is completely original, by the same transistor tw1o Switch. Each has its...

  • Water-Leak Alarm

    2016-02-18 22:24:5369

    If you choose to make your own moisture sensor,; this foil pattern should come in handy. A sensor connected to J1 causes S CR1 to conduct, which sounds...

  • Automotive burglar alarm

    2016-02-18 22:13:2661

    The car alarm is triggered after 13 seconds of delay and stays in 1-1 VFE minutes. Then, it can also turn off and reset open and reclose the SI. The ca...

  • How to build An Expandable Transistor Based Burglar Alarm

    2016-02-18 21:54:0666

    Description This is a simple transistor based burglar alarm circuit. Its features include automatic Exit and Entry delays - together with a timed Bell ...

  • NAND Gate Clock Generator circuit diagram

    2016-02-18 21:45:18211

    The following diagram is the Clock Generator circuit diagram which build based on NAND Gate logic IC. You may use IC 7400 or 4011 for this circuit. The...

  • Tone Generator-Ding-Dong Bell

    2016-02-18 21:41:3288

    Tone Generator Circuit Description Here we present a simple and low cost tone generator circuit, a ding dong bell suitable for calling bell purposes.It...

  • Auto Alarm

    2016-02-18 21:15:2165

    Before arming circuit IOD, LED1 lights green. Before arming circuit SI operation, allowing the alarm 0 after - 45 seconds delay time. SI is the externa...

  • Temperature alarm circuit

    2016-02-18 21:12:5869

    Thistemperature alarm circuitcontinuosly monitors the room temperature and beeps when the temperature drops below 20 degrees centigrade. This capabilit...

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