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Meter Counter Circuits
Digital voltmeter circuit diagram with single + 5V power supply composed of ICL7107
Frequency meter with 10Hz to 2MHz
7208 seven metric system counter is used for frequency meter, it has latch and multiplexing function, and contains direct drive circuit and display driver circuit. 7207IC is divided the output frequencyof6. 5536 MHz crystal oscillator by2 12which produces the 1600Hz square wave for calculator and display connection multiplexing. After fractional fr
Intelligent digital voltmeter circuit diagram composed of HI7159A
PH meter probe amplification circuit diagram
The interface circuit between single-chip accelerometer MMA1220D and microcontroller
The microcontroller within A / D converter can use PIC MCU within A / D converter produced by the Microchip. MMA1220D`s state end and self-test end are connected to the P1, P0 ports of ?C, its output voltage is sent to the A / D converter input end. C1, C2 are the power supply decoupling capacitors. A / D converter`s reference voltage side (...
Thermometer meter slinger 2
The thermometer meter slinger circuit is composed of power supply circuit and meter slinger timing control circuit, it is shown in the figure 9-135. The power supply circuit is made of fuse FU, power supply button S(Sa, Sb), resistors R1, R2, capacitors C1, C2, power supply indication LED VL, steady voltage diode VS and rectifier diodes VD1. The m
Using LB1413 as electronic thermometer circuit diagram
VU meter circuit diagram composed of M3916
LCD electronic thermometer circuit
Related components PDF download: ICL7106CD4036 The LCD electronic thermometer The LCD electronic thermometer circuit is as shown. The temperature sensor KTY10 has good linear relationship between temperature - resistance, and you can connect point A and point B (Measurement display circuit) with 100m wire, the digital display range is -50? to...
Digital frequency meter course design circuit
Microcontroller Based Digital Lock-In Milliohmmeter 2
The electronic thermometer circuit diagram for blind
Measuring range: room temperature is -10 ~ 40 ?; body temperature is 36 ~ 41 ?; Resolution: room temperature is 0.5 ?, body temperature is 0.05 ?; error: room temperature <1 ?, body temperature <0.1 ?. When S1 is in position 1, it shows the room temperature profile; position 2 is the body temperature profile. V1, R1, R2, RP1, RP2 form the...
555 ASTABLE_FREQUENCY METER
The circuit shown is a simple digital frequency meter, which indicates the frequency in hertz of an astable 555 timer. It could, perhaps, be adapted for other uses. An NPN transistor, TR2, is connected to the 555 astable to be measured, as shown in the in-set, and the output signal obtained is hooked to the main circuit via transistor TR1...
ANALOG FREQUENCY METER
This 1-kHz linear-scale analog frequency meter circuit uses the 555 as a pulse counter. Frequency is read on M1, (or 1 mA meter) which can be calibrated to read 0 to 1 kHz..
Analog frequency meter circuit
The circuit can measure the frequency between 1. 5kHz ~ 500kHz by connecting C1 ~ C6 different capacitors. The maximum frequency is up to 1MHz. Transistor T1 can be used as the integrator, and its load resistor is 15k © resistor and R1 ~~ R6 adjustable resistors. Integrator`s input signal is about 4 to 10V ( peak - peak value).
Audio Level Meter circuits
BIKE SPEEDOMETER CIRCUIT
The proximity detector senses the passing of the PC board pieces as the wheel rotates, providing an output signal, which has a clean transition between high and low voltage levels, and is ideal for triggering counting or processing circuits. Next is the frequency-to-voltage converter, and, because a reasonable degree of accuracy is required, the...
DIGITAL VOLTMETER CIRCUIT
A basic digital voltmeter circuit using the Harris Semiconductor ICL7107 is shown. It has a 2-V range. Calibration consists of applying a known voltage of 1.2 V to the input and adjusting R3 for a correct reading on the display. Supply is ±5 V, and S1 selects either the supply voltage or an external reference..
Frequency Meter with 100 MHz RF desktop channel
LC Meter Based on the AVR Microcontroller
LED VU Meter with LM3914N
The circuit is based on an LM3914N bar graph display driver device (IC1), which can be used to drive up to ten LEDs. This is connected so that with OV12 at the input only the first LED indicator switches on. This simple peak reading VU meter circuit uses six LEDs to indi-cate six signal levels at 14, 8, 3, 0, +3, and +6dB, or any other levels...
SIMPLE INDUCTANCE METER
This figure shows the schematic diagram of the simple inductance meter. U1, a 74LS00 two-input quad NAND gate logic integrated circuit, two resistors, a capacitor, and a surplus microprocessor crystal form a stable crystal oscillator near the marked frequency of the crystal. The RF voltage is taken from pin 8 through isolation capacitor C3 to...
SIX RANGE LIGHT METER
Switching of feedback resistors for opamp driven by Radio Shack 276-115 selenium solar cell gives multirange linear light meter. With 1000-megohm resistor for highest sensitivity, star Sirius will produce pho-tocurrent of about 25 pA when aolar cell is shielded from ambient light with length of cardboard tubing. Supplies are 9 V, and meter is...
Thermistor electronic thermometer circuit diagram
The thermistor RT and R1, R2, R3 and RP1 form a temperature measurement bridge. When temperature is at 20 ?, using R1, R3 and adjusting RP1 can allow bridge to keep balance. When temperature rises, the resistance of the thermistor RT reduces, the bridge in an unbalanced state, the imbalanced voltage output by bridge is amplified by operational...
VOICE LEVEL METER
Using an LM3915 VU meter LED bar graph driver?10 LEDs are driven?A simple audio amplifierdrives a detector circuit?which provides dc drive for the LM3915..
AC/DC 3 digits voltmeter circuit
The input stage of this voltmeter circuit uses operational amplifier and diode feedback to form linearity peak value rectifier circuit. Through R2/R2 partial pressure isolation, it is sent to double multi-channel BCD output A/D converter CA3162E, it also can add 0~1V DC tested voltage to CA3162E differential input terminal between ? and ?, If ?...
This circuit shows an ICM7217 and an ICM7555 that are connected as a basic frequency counter. The connections between the ICM7217 and a common-cathode LED display are shown in Fig. 12-18. The frequency counter is calibrated (against a known standard) using RA as a coarse control and RB as a fine control.Notice that the ICM7555 timer is connected...
The LED car voltmeter (2)
Here is to introduce the LED car voltmeter which is made of the op-amp LM312 and LED, it can display 6 gears of voltages, 10-15V, each gear is 1V. The working principle of the circuit The LED car voltmeter consists of the regulator circuit, Vref circuit, sampling voltage circuit and LED display drive circuit, see as figure 7-76. The regulator...
The LED car voltmeter (3)
The LED car voltmeter consists of the filter circuit, voltage distribution filter circuit, voltage amplifier circuit and LED display circuit, see as figure 7-77. The regulator filter circuit consists of the 3-terminal IC1 and filter capacitor C1. The voltage distribution filter circuit consists of the resistors
The electric thermometer circuit composed of LM134
This is the electric thermometer circuit composed of LM134. In the circuit, the voltage or current output by LM134 is in proportion to the thermodynamics temperature, which can be read out on the 100?A meter, the test temperature range of the meter is -55?150?. The power supply can work even when the voltage is under 1V, but when the precision...
The thermometer circuit composed of LX5600
When this thermometer is used in the room, it can work in the intermittent way, and this working state can be kept in the temperature test circuit, because internal temperature doesn`t change sharply. The astable multi-resonance oscillator consists of VT1 and VT2, i.e the interval oscillator circuit, which samples per 1s, and the interval time...
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...
Digital Signal Integrity
Interconnection and Timing of Digital Circuits
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