circuit wiring

This 5v power supply circuit is designed using the LTM8021 and will provide a maximum current up to 500mA. Almost all required parts are included in the LTM8021 package. This 5v power supply circuit based on the LTM8021 operate over a input voltage range between 3V and 36V .The LTM8021 supports an output voltage range of 0.8V to 5V, set by a single resistor. Only an output and bulk input capacitor are needed to finish the design.

5V Power Supply Circuit diagram

Description


Circuit showing a 9 volt power supply .
Here we have used a bridge rectifier and 7809 ic for making this circuit.Where the ic regulate the output to 9 v,1 A .This voltage every time constant.Are you interested ?

Component Required

Diodes

            IN 4007 -4

Capacitor

              C1   1000 MFD/16v
IC
               7809
Transformer

                9-0 V  ,1 A


source by : http://www.electronics-circuits.in/2012/02/9-v-power-supply.html

This is a water sensor circuit design using based on a Conductive Liquid Level Sensor, this single chip circuit is very compact and simple. This circuit is an ac excited fluid level sensor, which uses alternating current to provide biasing for the sensor probe to avoid electrolysis of the probes.  This ac excitation makes the sensing probe has longer lifetime. This circuit can be useful for wide range of water  or liquid level sensing  and control such as radiators, beverage dispensers, washing machines, water softeners,  irrigation, reservoirs, boilers,  aquarium,  or sump pumps

Many type of fluids are electrically conductive and can be detected using this liquid level sensor circuit: city water/ground water, sea water, chopper sulfate solution, weak acid, weak base, household ammonia, water and glycol mixture, wet soil, coffee,  or fruit juices. Remember that most of fuel doesn’t conduct electricity, so this circuit can be employed as fuel level sensor/detector. This is the figure of the circuit.

If we look at its data sheet, this water level sensor circuit chip is best at 10-24 volt supply voltage. The absolute maximum voltage supply for this liquid level sensor chip is 28V, but remembers to always try to avoid this extreme condition to prevent damaging the chip.

In the first circuit, a basic low level warning application uses a LED to indicate the water level falls below the sensor. You can see the filter pin (9) is not connected, this means that the LED is actually blinking at sound frequency, but it’s fine since our eye response is slow enough to notice such high speed blinking. Since without filter capacitor at pin 9 the output give a square wave signal, you can easily replace the led with loud speaker as shown in the second circuit to give audio indication. If you need a TTL or CMOS level then you should use a filtering capacitor connected to pin 9 and use the open collector output to drive a pull up resistor connected to a voltage supply at desired voltage level. For water level control, or any conductive liquid level control, you can use a relay to activate a motor or valve to control the level. The third circuit show this kind of application,  and the relay can be seen as liquid/water level switch. The optional resistor seen in the third circuit is an option for high voltage transient that often occurs in automotive environment, and you can omit it if  there is no such possibility. [Circuits schematic diagram source: National Semiconductor Application Notes]

Description

               Circuit showing a Burglar Alarm.Here we have used a ldr and a switching transistor for making this circuit
.When the light coming towards the ldr during the period the ldr have low resistance so the buzzer will on.When the light going away the ldr during the period the ldr have high resistance so the transistor will off.Here you need a 12 volt power supply

 Components Required

      Resistor

                   10 k(preset)

      Transistor


                   BC 548

       LDR


        Buzzer



Source by : http://www.electronics-circuits.in/2012/03/burglar-alarm-ldr-bc-548.html

this source from swagatam at http//homemadecircuitsandschematics.blogspot.com/2011/12/constant-torque-dc-motor-speed.html