Frequency Meter Circuits
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This small device, intended primarily for modellers, allows an instant reading of the time I of a pulse in ms. It can, for example, measure the position of the servomotors, about 1 to about 2 ms, or make repetitive or non-pulsed measurements, such as closing.... -
FIG. 555 and R1, C1 and other components monostable delay circuit, the input square wave signal or square wave signal by a Schmitt trigger shaping after the trigger requirement.. -
Direct reading frequency meter by the amplifier, and trigger one-shot circuit and table top components. It can be directly detected in the read head of the table 1mA signal, th.. -
If the input frequency is known, the timer can easily be used as a frequency divider by adjusting the length of the timeing cycle. Figure shows the waveforms of the timer when used as a divide-by-three circuit... -
Here is a simple tachometer circuit for use with a hand-held DVM or portable chart recorder. A novel feature is that the source frequency pulse/rev rate can be directly set on a ten-turn potentiometer to provide a convenient calibration of one V per 1000.... -
The figure shows the use of a CD4016 analog multiplex to multiplex the digital outputs back to the FUNCTION input. Since the CD4016 is a digitally controlled analog transmission gate, no level shifting of the digit output is required. The CD4051's or.... -
The ratio of capacitors Cl and C2 determines division. With a positive pulse applied to the base of Ql, assume that Cl = C2 and that Cl and C2 are discharged. When {31 turns off, both Cl and C2 charge to 10 volts each through R3. On the next pulse to the.... -
This is a minimum component complete Universal Counter. It can use input frequencies up to 10 MHz at INPUT A and 2 MHz at INPUT B.. -
The meter will indicate the frequency from a power generator. Incoming sine waves are converted to square waves by the 100K resistor and the 6,8 V zener. The square wave is differentiated by the capacitor and the current is averaged by the diodes. The.... -
In this configuration, the display reads hertz directly. With pin 11 of the ICM7027 A connected to V00, the gating time will be 0.1 second; this will display tens of hertz as the least significant digit. .. -
The circuit converts frequency to voltage by taking the average de value of the pulses from the 7 4121 monostable multivibrator. The one shot is triggered by the positive-going ac signal at the input of the 529 comparator. The amplifier acts as a de.... -
The output frequency from IC pin 3 is determined by the voltage input to pin 6. A standard frequency counter can be used to measure voltages directly over a limited range from 0 to 5 V. In this circuit, the 555 is wired as an astable multivibrator..... -
This is a schematic and block diagram of a 2-MHz frequency counter. It uses and LSI counter/display driver, LCD readout, and a few logic chips for timebase and timing pulse circuitry. Q2 and Q3 form a signal (input) amplifier. The circuit contains a crystal.... -
The circuit consists of an ICM7208 seven-decade counter (Ul), an ICM7207A oscillator controller (U2), and a CA3130 biFET op amp (U3). Integrated circuit Ul counts input signals, decodes them to 7-segment format, and outputs signals that are used to drive a.... -
This system uses an MM5369 IC to derive a 60-Hz signal from a TV burst crystal (3579 MHz). F8 and V9 producc a 10-Hz and 1-Hz signal from this 60-Hz signal... -
This meter differs from the norm in that it does not use a D`Arsonval movement or digital display to give a reading of the input frequency. Instead, the measured frequency is read from a hand-cali-brated dial. Any audio signal applied to the circuit is.... -
This circuit uses the low power ICM7555 (CMOS 555) to generate the gating, STORE and RESET signals. To provide the gating signal, the timer is configured as an astable multivibrator. The system is calibrated by using a 5 M potentiometer for Ra as a coarse.... -
This counter makes direct readout of frequency-generating equipment very easy when a 1-H.. -
This circuit is meant to be driven by a 1-MHz standard signal of a few volts amplitude. Ul through U5 are 7490 decade counter/divider and produce a division ratio of 100,000:1. Successive divisions of 10 can be tapped off, if desired, between stages. .. -
The turn-on and turn-off characteristics of two complementary transistors can be combined to attain nonselective frequency tripling. The resulting circuit handles any periodic waveform with nonvertical sides. Each input signal peak produces three output.... -
The ICM7216A or can be used as a minimum component complete Universal Counter. This circuit can use input frequencies up to 10 MHz at INPUT A and 2 MHz at INPUT B. If the signal at INPUT A has a very low duty cycle it may be necessary to use a 74121.... -
Circuit using an ordinary digital quartz electronic watch, the lower its crystal welding, as shown by the connected circuit constitutes a digital frequency meter. The test sign.. -
Recently, I have needed to measure inductances in the hundreds of microhenries to several millihenry range. Though I have a pretty good LRC meter and an excellent bridge on my workbench in Mesa, Arizona, I wanted to make these measurements in my home in.... -
The following circuit enables me to measure inductance of the inductor labeled LX which is the inductance to be measured. The o/p of the circuit is a TTL square wave whose frequency relates to the inductance being measured. The heart of the circuit is the.... -
Finally, white LED`s are bright enough to use in a practical stroboscope. This circuit can operate as a bench-top stroboscope that, in conjunction with an oscilloscope or frequency meter and bench top power supply can accurately measure rotational speeds, or.... -
Having found an u664b prescaler chip (Telefunken) from an old tv-tuner , I decided to build a valid frequency counter using pic16f84 , the prescaler I use is able to divide by 64 every frequency from 30 to 1300 MHZ. The original project is from Peter.... -
This project has 3 features. 1. It`s a Field Strength Meter, 2. A Frequency Meter and, 3. An aid for testing detuned transmitters. Its uses will become clear in a moment but firstly let`s go over the background of a Field Strength Meter. A Field.... -
This is a handy companion for a digital voltmeter. Its allowed me to do a lot of things I used to use my oscilloscope for, and in addition it measures voltages to much greater precision.Using an LM324 quad op amp, this peak detector provides 2% measurement.... -
This basically the frequency meter section of the frequency meter/pulse generator based on the AT90S2313 described elsewhere on this site, combined with the 100 MHz RF interface described in the page about the RS-232 to 100 MHz RF desktop channel adapter..... -
This instrument requires two precision components: A precision capacitor and a precision inductor. You only need to start with one precision component, either the reference capacitor or the reference inductor, and using this meter, you can select or adjust.... -
If this picture (above) looks a lot like the Pretty Good LC Meter also on this web site, that's because its the same meter, but with some significant improvements. At this point, its a good idea to read the Pretty Good LC Meter page because the rest of this.... -
The circuit's operating principle is that if you make a pulse width proportioal to inductance, and keep the pulse frequency and amplitude constant, and then pass the pulse through a low pass filter so that only the average voltage comes out, the resulting DC....
New Circuits
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This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
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.... -
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.... -
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.... -
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.... -
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,.... -
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.... -
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.... -
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.....
Popular Circuits
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