Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Meter Counter Circuits
Thermostat with three-wire serial interface smart temperature sensor DS1620 configuration control circuit
DS1620 with a microprocessor to monitor temperature, by opening or closing the fan can be changed thermal conditions of the chip to achieve temperature control circuit as shown
FGDF-3 three-phase low-temperature iron plating main circuit
FGDF-3 three-phase low-temperature iron plating main circuit KGDF-3 low-temperature iron plating power supply device having a single-phase low-temperature iron plating all the
Electronic thermometer circuit
Electronic thermometers as shown in the circuit. RT is the thermistor, A is an integrated operational amplifier. VD1 ~ VD4 composition marked by the scribe mushroom flow channe
Three temperature switch circuits
Electronic temperature control circuit on an imported car air conditioners. Operational amplifier Ai, A2 using LM393. Adjustment potentiometer RP. Temperature range can be chan
OP27 multiple S-type thermocouple circuit
Electronic switch selection, you can achieve multiple temperature control, or a plurality of temperature monitoring points, monitoring. OP27 multiple S-type thermocouple circui
TC621 temperature sensor using poultry hatchery electronic thermostat control circuit diagram
Eggs hatch chicks temperature requirements within 36 ~ 39oC temperature range, temperature sensor integrated circuits using TC621 temperature control circuit, having fewer exte
Dispenser Aucma temperature detection control circuit
Dispenser (Aucma) temperature detection control circuit It shows the dispenser (Aucma) temperature detection control circuit. The dispenser is composed of two parts, one part i
Electric thermos temperature detection control circuit
Electric thermos temperature detection control circuit Electric thermos shows the temperature detection control circuit. It is mainly by the control circuit of the boiler heate
SCR furnace temperature regulating circuit
Consisting of two differential amplifier transistors voltage dividing type bias circuit, and this resistance is measured four bridge four of arm. Wherein the product is a plati
The CD4069 or 74C04 hex inverterâ€”is used as^ fixed-frequency oscillator centered around 100 kHz. U2 contains the variable frequency oscillator and balanced modulator. The CD4046 is a phase-locked loop and R3, R4, and C2 determine the center frequency of the on-chip oscillator. The antenna forms a parallel capacitance with C2, which allows the...
Temperature measurement using two cables
In those cases we want to measure the temperature in an area far from where it is. The imaging unit installed, you should find some way to connect the latter with the necessary sensor. The cables we use most often will have three two conductors for power sensor and one more to carry the signal representing the temperature. But it may have only...
This thermometer is capable of 0.01Â°C accuracy over - 50Â°C to +150Â°C. A unique trim arrangement eliminates cumbersome trim interactions so that zero gain, and nonlinearity correction can be trimmed in one even trip. Extra op amps provide full Kelvin sensing on the sensor without adding drift and offset terms found in other designs. Al is...
TCA965 window discriminator IC allows the potentiometers RVl and RV2 to set up a window height and window width respectively. Rl and thermistor THl for a potential divider connected across the supply lines. Rl is chosen such that at ambient temperature the voltage at the junction of these two components will be approximately half supply. As the...
The circuit exploits the fact that when fed from a constant current source, the forward voltage of a silicon diode varies with temperature in a reasonably linear way. Diode Dl and resistor R2 form a potential divider fed from the constant current source. As the temperature rises, the forward voltage of Dl falls tending to turn Ql off. The output...
This design measures the differential temperature between two sensors. Sensor Tl, located before the heater resistor, assumes the fluid"s temperature before it is heated by the resistor. Sensor TZ picks up the temperature rise induced into the fluid by the resistor"s heating. The sensor"s difference signal appears at Al"s output. A2 amplifies...
Filtered 15 V de is applied to a series circuit consisting of thermistor R2 and parallel combination of resistors Rl and R3. Transistor Ql acts as a switch whose state is determined by the setting of potentiometer R3, which is first set so just enough current flows into the base to switch on when the thermistor is in contact with air. When...
This circuit responds quickly enough to prevent damage from most overloads. C 1 "s input is connected to the output of the LT1088 servo circuit. If the LT1088 circuit"s output exceeds the threshold at Cl"s other input, C1 trips, discharging the 2-!"F capacitor. This causes C2"s output to become low, energize the relay, and break the heater...
When power is applied, the thermistor, a negative tc device, is at a high value. A1 saturates positive. This forces the LT3525A switching regulator"s output low, biasing Ql. As the heater warms, the thermistor"s value decreases. When itsinputs finally balance, A1 comes out of saturation and the LT3525A pulsewidth modulates the heater via Q1,...
Sensing element Ql is a 2N3904 general-purpose npn transistor, although any general-purpose npn unit in a T0-92 style case will do. IC1, an LM334, supplies Ql with a constant current that is independent of temperature. An LM324 quad op amp, IC2, forms a high input-impedance differential amplifier (IC2a, IC2b, and IC2c) with a gain of about...
To decouple the sensors from the meter amplifier, either a reference junction at ooc or a bucking voltage set at room temperature may be used. The latter method is simpler, but is sensitive to changes in ambient temperature.
The temperature sensor provides an input to pin 3 of the NE5037 of 32 mV/Â°C. This 32 mV is the value of one LSB for the NE5037. The LM334 is a three-terminal temperature sensor and provides a current of 1 p.A for each degree Kelvin. The 32-KO resistor provides the 32 mV for each microamp through it, while the transistor bleeds off 273 p.A of...
This circuit uses the +5 V reference output and the op amp to level shift and amplify the 2.1 mV/Â°C Tempco output into a voltage signal dependent on the ambient temperature. Different scaling can be obtained by selecting appropriate resistors from the table giving output slopes calibrated in degrees Celsius or degrees Fahrenheit. To...
A simple op amp and silicon diode are the heart of the temperature-to-voltage converter that will permit you to use an ordinary voltmeter-either analog or digital-to measure temperature. User adjustments make it possible for a reading of either 10 mV or 100 mV to represent 1 Â°F or C. Temperature sensor D1 is a 1N4148 silicon diode. It has a...
Thermocouple Temperature Control
This control, with zero-voltage load switching, uses a CA3130 BiMOS op amp and a CA3079 zero-voltage switc
A thermistor (RI) is compared with a reference (R2) in a Wheatstone-bridge circuit. Comparator Ul"s output goes high
Simple Temperature Indicator
For the absolute measurement of temperatures, a thermometer is indispensable. However, in many situations, an
The reference current is fed from the supply voltage via Rl, to the inverting terminal, and the variable (noninver
The AD537 uses its two reference outputsâ€”one fixed at 1 V, the other of which varies with temperature (1 mV per Â°K). At
The output goes high when a preset temperature is exceeded. A fixed half-supply reference voltage feeds a reference
Inexpensive Linear Thermometer
As a sensor in the design of this linear thermometer, the LM34 is used. The output is the difference between
This thermometer is capable of measuring temperatures from - 30 to +120 Â°F. A diode-connected 2N3904 transistor form
This circuit combines a current source and a platinum RTD bridge to form a complete high-accuracy thermometer. Th
Frequency Meter Circuits
VU Meter Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity