Rain Detector Using 555

Rain Detector Using 555 is a simple alarm that can be used to find out it was raining. In principle, Rain Detector Using 555 is an astable multivibrator which is prepared by IC555 with installed a sensor that can detect water. Astable multivibrator with the 555 is set in the audio frequency with a frequency of 1 KHz. The series of Using Rain Detector 555 can be disupplay with a voltage source that is free enough from 5-15 VDC. In the application circuit Rain Detector Using this 555 can be mounted motor, car or other object that we want to protect from rain.

Water sensors that are used in circuit 555 Rain Detector Using this we can make yourself degan a PCB that we make the path as shown in the image above or as disclosed from the image above is by using aluminum foil taped to a board or boards that are plastic insulator . The important principle of the sensor is to conduct electrical current very well when the surface is exposed to water even a little. Hopefully useful ...

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Laser Level Detector

Rotating laser levels, which are very handy  for setting objects in a room or garden at the  same height, are available at prices of a few  dozen pounds. At relatively large distances  and for outdoor use, the light from the rotating laser beam is often not easy to see, and  the laser beam detector described here can  be useful in such situations. The detector  works well at distances up to 50 metres (150  feet) and consists entirely of standard components. The detector is housed in a plastic case  that can be fixed to an object (such as a post  or a beam). It has three LEDs and a beeper that  indicate whether the object should be raised  or lowered. 

LEDs with a transparent package and integrated lens (round surface) are used as sensors. The top and bottom detection zones  each have five LEDs and two opamps (IC1a &  IC1b or IC1c & IC1d), which drive the ‘Move  Up’ and ‘Move Down’ indicator LEDs. The middle sensor LED drives the ‘OK’ indicator LED  via two opamps (IC2a & IC2b).  The rising edges of the opamp output signals  trigger three separate monostable multivibrators (type CD4047). If desired, the circuit  shown inside the dashed outline (one gate of a  CD4044 quad RS latch) can be used in place of  each of the monostable multivibrators. In this  case the output signal has the opposite polar-ity, so the BS170 N-channel MOSFET must be  replaced by a P-channel type. 

The monostable time of the middle retriggerable MMV should be longer than the rotation period of the laser (e.g. with a 2 rpm laser  it should be longer than 500 ms) so that the  beeper will emit a continuous tone. Most  rotating laser levels have variable speed, so  this can also be achieved by adjusting the peed if necessary. The monostable times of  the upper and lower MMVs are dimensioned  to generate clearly distinguishable short and  long beeps, respectively. The three MOSFETs  (T1, T2 and T3) are configured as a wired-OR  gate to drive the shared beeper. The fourth  MOSFET (T4) drives the ‘OK’ LED. 

The circuit can be housed in an enclosure  together with three penlight cells.

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Phone Cellular Calling Detector

Phone Cellular Calling Detector

This circuit was advised to ascertain back a alarm is admission in a cellular buzz (even back the calling accent of the accessory is switched-off) by agency of a aflame LED.

The accessory charge be placed a few centimeters from the cellular phone, so its sensor braid L1 can ascertain the acreage emitted by the buzz receiver during an admission call.

The arresting detected by the sensor braid is amplified by transistor Q1 and drives the monostable ascribe pin of IC1. The ICs achievement voltage is angled by C2 & D2 in adjustment to drive the high-efficiency ultra-bright LED at a acceptable peak-voltage.

Notes:

Stand-by accepted cartoon is beneath than 200µA, accordingly a ability on/off about-face is unnecessary. Sensitivity of this ambit depends on the sensor braid type.

L1 can be fabricated by ambagious 130 to 150 turns of 0.2 mm. enameled wire on a 5 cm. bore above (e.g. a can). Remove the braid from the above and wind it with careful tape, appropriately accepting a stand-alone coil.

A bartering 10mH miniature inductor, usually awash in the anatomy of a tiny ellipsoidal artificial box, can be acclimated abundantly but with lower sensitivity.

IC1 charge be a CMos type: alone these accessories can cautiously accomplish at 1.5V accumulation or less. Any Schottky-barrier blazon diode can be acclimated in abode of the 1N5819: the BAT46 blazon is a actual acceptable choice.

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4 x 12 W power amplifier with dynamic distortion detector and diagnostic interface

FEATURES
Requires very few external components
High output power
Fixed gain
Diagnostic facility (distortion, short-circuit and temperature detection)
Good ripple rejection
Mode select switch (operating, mute and stand-by)
Load dump protection
AC and DC short-circuit safe to ground and to VP
Low power dissipation in any short-circuit condition
Thermally protected
Reverse polarity safe
Electrostatic discharge protection
No switch-on/switch-off plop
Flexible leads
Low thermal resistance
Identical inputs.

GENERAL DESCRIPTION

The TDA8562Q is an integrated class-B output amplifier in a 17-lead single-in-line (SIL) power package. It contains 4 × 12 W single-ended amplifiers.

Circuit Diagram

4 x 12 W power amplifier with dynamic distortion detector and diagnostic interface

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RF AF signal detector

The series that we will make this is a special electronic circuit can be used to detect the presence or absence of signal AF / RF. The circuit is very neat and simple to make. Costs it takes quite cheap. If you are already assembling this circuit, then with easy reader determine whether there is AF or RF signal at a particular section of a circuit.

Basic circuit uses an audio amplifier and a loudspeaker with switch input for AF and RF signals. The whole device can be made small as possible so it can be included in a container to maintain security. Audio amplifier section in this series created by IC TDA 2822M, with low stereo power amplifier in 8-pin mini-DIP. IC is used as a bridge cofiguration to shrink to 250 mW output power, loudspeaker handle 4 ohm, 500mW. The current required is less than 10mA with voltage of 3V battery.

RF-AF signal detector schematics

How it Works circuit

When the selector switch in the AF position, working on the input audio signal AF amplifier input (pin 7 of IC 1) through a capacitor C2 and potentiometer VR1. Capacitors C2 always hold input amplifier of the DC voltage and make it happen in the audio signal frequency. Input Signal IC 1 can be arranged with the help of potentiometers VR1.

When the selector switch in position RF and demodulator detector circuit formed by capacitor C1, diode D1, and resistors R1 and R2 are connected to the input The set. When the audio signal is detected then it will actually go kerangkaian to be strengthened. Signal detection is done by plugging probe (probe) on the legs of the existing components.

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Simple Power Failure Detector Wiring diagram Schematic

Simple Power Failure Detector Circuit Diagram. This schema indicates that a power outage occurred for 1, 10, 100, and 500 seconds with the values given for R* and C* . After a power failure, the schema can be reset by pushing the Reset button.

Simple Power Failure Detector Circuit Diagram

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Active ir Motion Detector Wiring diagram Schematic

To explore how different motion detectors operate.To successfully build and test an ambient-light-ignoring active IR motion detector.

Background

 There are a wide variety of motion detectors available currently. To allow a better understanding of motion detectors,the following section provides a detailed description of a few different types.

Ultrasonic Motion Detectors

Ultrasonic transducers can be used to detect motion in an area where there are not supposed to be any moving objects.This type of motion detector is most commonly used in burglar alarm systems since they are very effective in this application.

 Figure 1 shows the operation of an ultrasonic motiondetector. There are tw1o transducers: one emits an ultrasonicwave and the other picks up reflections from the differentobjects in the area. The reflected waves arrive at the receiverin constant phase if none of the objects in the area are moving.If something moves, the received signal is shifted in phase. 

A phase comparator detects the shifted phase and sends a triggering pulse to the alarm.Ultrasonic motion detectors have certain advantages and disadvantages when compared with other types of motion detectors. The main advantages is that they are very sensitive and extremely fast acting. However, the largest problem with this type of motion detector is that it sometimes responds to normal environmental vibration that can be caused by a passing car or a plane overhead. Some types of motion detectors use infrared sensors to avoid this problem, but even these detectors have some problems.

 Passive Infrared Motion DetectorIn passive infrared motion detectors, a sensorcontaining an infrared-sensitive phototransistor is placed in thearea to be protected. Circuitry within the sensor detects theinfrared radiation emitted by the intruder`s body and triggersthe alarm. 

The problem with using this type of detector is that it can be falsely triggered by warm air movement or other disturbances that can alter the infrared radiation levels in an area. In order to prevent this problem, newer systems use tw1oinfrared sensors which monitor different zones within a protected area. Logic within system triggers the alarm only when the tw1o zones are activated in sequence, as would occur if a person walked through the protected area.

Active Infrared Motion Detector

Figure 2 shows the operation of an active infrared motion detector. In the active system each sensor consists oftw1o housings. One housing contains an infrared-emitting diode and an infrared-sensitive photo transistor. The other housing contains an infrared reflector.When positioned in front of an entrance to a protected area, the tw1o housings establish an invisible beam. A person entering the area interrupts the beam causing an alarm to be triggered. An active motion detector is much more reliable than a passive one, but it requires careful alignment when it is installed. The detector can be falsely triggered if one of the housings moves slightly and causes a discontinuous beam.

Project

 For our project, we decided to construct an activeinfrared motion detector. Originally, we wanted to build both anIR and an ultrasonic detector, but we decided that an ultrasonicdetector would require too much time for a three week project.However, we also decided that just building an IR motiondetector would probably be a trivial exercise. 

So, we decided to expand on the concept by building an ambient light ignoring motion detector.This type of motion detector uses the same basic concept as the active infrared motion detector. An interruption in a 5kHz modulated pulsating beam that is transmitted by an infrared diode and received by an infrared transistor sets off the alarm. A schematic of this motion detector is given in Figure 3.

 Figure 3. Ambient-Light-Ignoring Active Motion Detector

The schema on the left is the transmitter schema that establishes a 5 kHz modulated infrared beam. As you can see from the schematic of the receiver schema, a resonance-handbarrow amplifier reduces the detector`s sensitivity to stray light. C1 and L1 in IC2A`s feedback loop cause the op amp to pass only those frequencies at or near the LED`s 5 kHz modulation rate. IC2B`s output increases when the received signal is sufficient to drop the negative voltage across C2 below the reference set by R2. The output of this schema is then attached to some load resistance, which can be an alarm or, for demonstration purposes, an LED.

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