This is the circuit diagram of seismic / vibration sensor. The circuit simulates a seismic sensor to detect vibrations/sounds. It’s really sensitive and may detect vibrations due to the motion of animals or human beings. So it could be utilized to monitor protected locations to restrict entry of undesirable individuals or animals. The circuit applies… Read More »
Above circuit design is thermocouple amplifier circuit using CA3193 operating amplifier. The CA3193 is an excellent choice for use with thermocouples. In the circuit, the CA3193 amplifies the generated signal 500 times. The three 22MΩ resistors will provide full-scale output if the thermocouple opens.
This is a ultrasonic motion detector (or movement detector) circuit. The circuit claimed has a high movement sensitivity. Even air moving (hot air rising, wind blowing) will trigger it when the trimpot is set near the most sensitive position. The transmitter sends out a steady ultrasonic tone at 40kHz. At this frequency the wavelength is… Read More »
This is a very easy build, simple metal detector circuit, built based on a CS209A IC. The circuit will give surprising results and draws extremely small current from a 9 volt battery. It worked great on the bench, but not so good outside for common metal detecting. But definately a great circuit for sensing studs… Read More »
I’ve found some interesting schematic of load cell amplifier. As we know, load cell amplifier is pretty expensive with fair price range of 100-300 USD. You may built your own load cell amplifier to get the lower cost. Here the two scheme diagram of load cell amplifier circuit: Load Cell Amplifier using AMP04: source: http://cgi.ebay.com/Load-Cell-Amplifier-Improved-Better-Stability-New-/350451149452
Touch alarm circuit is widely used for security, which is installed on the door. The advantages of this alarm is because the cost is cheap and difficult to detect by burglars / intruders. The following is an example of a touch of alarm circuit which is designed by Tony Van Roon. Components List: R1 =… Read More »
A well-known IC LM35 is chosen to be the temperature sensor in this circuit. Output voltage of LM35 will increase by 10mV per degree rise in temperature. Output of LM35 is joined to the non inverting input of the operational amplifier (op-amp) of CA3130. The inverting input of the same op-amp could be provided using the required reference voltage using variable resistor R2.
The following circuit diagrams are tone detector circuit diagrams which also known as sound activated switch circuit. Actually, these circuits use microntroller for switching because the circuits were designed for robot start up activation. But you can build switching module using relay. You may make a trial to use this circuit for other applications such… Read More »
This is the basic dark and light sensor which using photoresistor as sensing component. The transistor act like as a switch, when the “switch” in on condition then the relay will be activated.