Archive for tag: Meter

Car Water Temperature by CA3161 CA3162

Automotive Wiring | By: Diagram mania

The circuit measures the car water temperature. CA3161 , CA3162 is a counter and 7segment driver to display amount of temperature on 7segments. The temperature sensor is a diode, 1N4148. This is set near of the Car Radiator. To obtain the 5V power supply from Car Battery, you can use a LM7805, +5V low cost […]

Car battery Volt meter circuit using LED

Automotive Wiring | By: Diagram mania

This is a very useful circuit which when installed on your car gives the voltage of you car battery in a LED dot display form.The circuit is based on four comparators made of quad op amp LM324.The inverting inputs of IC are kept at at reference voltages 5.6V,5.2V,4.8V,4.4V respectively at pins 2,6,9,13 by resistors ,R3,R4,R5,R6.The […]

Lambda Probe Readout For Carburettor Tuning

Automotive Wiring | By: Diagram mania

A lambda probe (or oxygen sensor) can be found on the exhaust system of most cars running on unleaded fuel. Having reached its normal operating temperature (of about 600 degrees Celsius!) the lambda probe supplies an output voltage proportional to the amount of residual oxygen measured in the exhaust gas. This information is indicative of, […]

LED VU Meter by LM339

Lighting Circuits Diagram | By: Diagram mania

The circuit below uses two quad voltage comparators (LM339) to illuminate a series of 8 LEDs indicating volume level. Each of the 8 comparators is biased at increasing voltages set by the voltage divider so that the lower right LED comes on first when the input is about 400 millivolts or about 22 milliwatts peak […]

Low Power LED Voltmeter by LM3914

Lighting Circuits Diagram | By: Diagram mania

This is a low power voltmeter circuit that can be used with alternative energy systems that run on 12 and 24 volt batteries. The voltmeter is an expanded scale type that indicates small voltage steps over the 10 to 16 volt range for 12 volt batteries and over the 22 to 32 volt range for […]

Comparator Oscillator Circuit by LM311

Lighting Circuits Diagram | By: Diagram mania

Comparator Oscillator Circuit by LM311 or LM339 Comparators can also be used as oscillators but are not well suited for this type of application. Source : http://home.cogeco.ca/~rpaisley4/Comparators.html

4 Level – voltage Detector by LM339

Lighting Circuits Diagram | By: Diagram mania

This circuit can sequentially indicate 4 separate voltage levels. The voltages are determined by the values of resistors R1 through R5 arranged in a simple voltage divider circuit. Source : http://home.cogeco.ca/~rpaisley4/Comparators.html

Audio Indicator by 741

Lighting Circuits Diagram | By: Diagram mania

This circuit can be used to remotely monitor a loudspeaker, alarm, or audio source for presence of an audio waveform. It can also be directly connected across loudspeaker terminals used as a peak indicator. If you need to monitor some audio signal at a location that is either soundproof are too far away to actually […]

Temperature Monitor with IC LM741 or LM301

Control circuits | By: Diagram mania

My Friend want circuit Temperature Monitor for control relay. I find on internet , See to This Web http://www.mitedu.freeserve.co.uk/Circuits good article circuit. The Temperature Monitor use IC LM741 or IC 301 for test Temperature control relay switch. read more detail: Using a thermistor in the position shown makes a heat activated sensor. A change in […]

High Temperature ALARM by BC550

Control circuits | By: Diagram mania

The circuit is small regulatorof temperature, us warns for the increase of temperature. The control of temperature becomes from the thermistor TH1, that is negative factor. His resistance is altered between in the 10K in temperature 25° C and roughly in the 1K in their 94° C. The trimmer TR1 regulates the precise temperature in […]