This is an electrical circuit protection device sound disappeared. when too much voltage 220V, and protection when pressure is too low with Using the relay cut off power when voltage problems. In particular, If the voltage of motor is lower, the coils of it can be a burn.
The working of circuits
From the circuit when the voltage is 220 volts AC through a transformer T1. It serves to reduce the pressure remaining 12 volts, through a D1-D4 connected to Direct rectifier bridge circuit. To convert the voltage, alternating current to direct current. Then, through the C1 and C2 to the power filter smoothing. And entering a pin. Or input pin of IC1, a loan IC Rex bit computing to 12-volt power supply is fixed to the IC2. That it is IC Op Amp. Pressure acts edge IC2/1 High Voltage Detector, High Voltage ICs,…
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Car Exhaust Meter
Bridge circuit contains two resistors lOO-ohm (R3 and R4), and two thermistors (Tl and T2). At room temperature, the resistance of T1 and 1’2 is about 2000 ohms. When they are each heated to 150 °C by an RNA 10 current, the resistance value decreases to 100 ohms. So. the four elements include a bridge
Air Flow Detector
This simple circuit uses an incandescent lamp to detect airflow. With the filament exposed to air, a constant current source is used to slightly heat the filament. As it is heated, the resistance increases. As air flows over the filament it cools down, thus lowering it’s resistance. A comparator is used to detect this difference
Self-heated transistor digitizes airflow
A sensitive and reliable way to measure airflow is to exploit the predictable relationship between airspeed and the heat dissipated by a sensor exposed to the flow while being held at a constant temperature differential above ambient. The power required to maintain the elevated sensor temperature is proportional to the square root of the airspeed
Read more Airflow sensitive circuit
This circuit can use with power supply since 5 volt until 25 Volt. When voltage of power supply or battery agree come to lower location level keeps. It make LED bright show know. Although the circuit this use how many is the equipment not, but there is the stability and accurate in good moderately work. Because of use IC Voltage Detector 8211 that bring build be Voltage Comparator Circuit. Which have Voltage Comparator at certainly stay within the integrated circuit. Read more and view circuit diagramContinue Reading »
FM surveillance BuG Transmitter using 2N2222 Nov 7, 2008 … The Circuit shown can transmit voice to exceptionally good range. Tune trimmer to hear the signal to your near radio. Frequency range is …
FM telephone bug Jun 18, 2010 … A simple telephone transmitter circuit that is ideal for transmitting the telephone conversation through small distances.The circuit is very simple …
Mobile Bug Detector using CA3130 Sep 6, 2010 … This handy, pocket-size mobile transmission detector can sense the presence of an activated mobile phone from a distance of one-and-a-half …
Bug Detector Circuit Mobile Bug Detector using CA3130. Monday, September 6th, 2010. This handy, pocket-size mobile transmission detector can sense the presence of an activated …
Telephone Listening Bug with FM Transmitter by A933 Mar 7, 2008 … Here is a simple transmitter that when connected to a phone line, will transmit anything on that line (execpt the dial tone) to any FM radio.
Telephone Listening Bug by A933 Jul 12, 2008 … Here is a simple transmitter that when connected to a phone line, will transmit anything on that line (execpt the dial tone) to any FM radio.Continue Reading »
This circuit will detect AC line currents of about 250 mA or more without making any electrical connections to the line. Current is detected by passing one of the AC lines through an inductive pickup (L1) made with a 1 inch diameter U-bolt wound with 800 turns of #30 – #35 magnet wire. The pickup could be made from other iron type rings or transformer cores that allows enough space to pass one of the AC lines through the center. Only one of the current carrying lines,.
Read more and view circuit at : AC Line testing circuit