Questions tagged [frequency]
How many times something happens per second, measured in Hz (hertz).
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Increasing power of a standalone circuit board
I am a rookie at potentially upgrading some electronics and wanted to see if I could get a little direction on a potential first project.
I purchased a small frequency generator and would like to ...
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Reading a spectrum analyser in MATLAB
When demodulating an AM waveform why is there a frequency spike on the spectrum analyser of exactly two times the carrier frequency with an upper and lower sideband. It is past the cut off frequency ...
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How can I compare these two frequencies? [closed]
I want to make a metal detector using an STM32F103C8T6.
I want to compare the PWM signal from the STM32 to the search coil's signal. When the search coil's signal is higher or lower than the STM32 ...
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How can prevent the source voltage from dropping when using a 555 timer
I am trying to use a 555 timer in my circuit to produce a signal (rather generally) above 100kHz. I have been successful with this goal, but have had an issue where the voltage measured on my positive ...
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WCCA analysis - Induction selection - Mismatch with recommendation at low current values
I'm performing the WCCA analysis of a 3.3V buck regulator(AP64200Q).
Datasheet: https://www.diodes.com/assets/Datasheets/AP64200Q.pdf
In the current circuit:Vin=24V,Vout=3.3V,Max.current=300mA so ...
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Tips on Building An Analog VCO
I am attempting to build an analog VCO. Many of the resources I see online implement a 555 timer, but I am trying to avoid that, solely for the sake of learning how to do this in purely analog. Here ...
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What are the effects on the converter circuit due to lower vs higher switching frequency?
I know that lower frequency and higher frequency are selected based on the application. But I read that higher frequency will usually have more EMI harmonic distortions. It would be nice if anyone ...
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Finding device Tx frequency with Yardstick One
I wanted to get into RF hacking (to decode and reproduce ceiling fan control), and decided to buy a Yardstick one. After having played with the YS1 for a while I now better understand that it is NOT ...
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NF (Noise Figure) calculation - task
In a 622 Mbps radio-link interface, it was assumed that the BER would
be 10^-10 when the signal-to-noise ratio at the receiver point is 7.8
dB, while its sensitivity for a fixed modulation-code scheme ...
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How are different GPIO frequency modes implemented?
An MCU GPIO's slew rates may be increased, or decreased, and this allows setting the maximum GPIO switching speed. But how is it implemented on hardware level?
I know that those outputs are ...
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Does a higher switching frequency in SiC MOSFET mean higher efficiency?
https://www.we-online.com/en/news-center/blog?d=design-drivers-sic-mosfets
From this link, it says "The SiC MOSFET's extremely fast switching speed helps to achieve higher efficiency".
Is ...
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How crystal ensure stable frequency?
I know the crystal frequency (series also parallel) is given by its properties however I don’t understand how can crystals hold the stable frequency when power supply of oscillator changes. Like LC ...
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Boost low frequency sine wave to high frequency
I have a 50 Hz sine wave, which I need to convert to 1 kHz synchronously without delay. Can anybody suggest a method to do so?
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Low power low speed pulse divider?
I have a digital input which receives irregular pulses. I want a circuit that takes that input and generates an output pulse for every 100 (or so) input pulse. The expected input speed is 10-300 Hz. I ...
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Current sense transformer outside its freq range
What happens if I use a current sense transformer outside its specified frequency range? For example a transformer is rated for 20-200 kHz but I want to use it to measure 50 Hz power line frequency ...
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Why is the Gb/s usually matched with the GHz for SDI?
My knowledge in electronics and RF(because high speed data) is very surface level but attempting my best.
I'm attempting to do an application which utilizes 3G SDI, but am not understanding why there ...
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DC-DC current mode control frequency behavior
On a buck converter in average current control mode, for example, the inner current loop sees and manages the double pole created by the LC filter, and thanks to this the outer voltage loop is blind ...
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More voltage for radio carrier frequency, is that all?
I soldered one radio circuit for a wave transmission with ~107 MHz frequency and I got good results. I simulated this circuit in LTSpice, too. What I have seen was that the wave got AM modulated and ...
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How to measure the frequency of a low frequency signal?
I am looking to measure the rpm of a wind turbine,
the wind turbine is 3-phase synchronous generator,
the frequency range I am looking to detect is between 1Hz to 60Hz,
I tried to use a frequency ...
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Why does an AC Voltage reading on a DMM decrease as the frequency is increased?
I'm doing an assignment for a lab and I've found that frequency doesn't affect the voltage reading of an oscilloscope while it does for a DMM. Online, it says this is because an oscilloscope displays ...
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Measuring electric generator AC frequency
I need to measure the AC frequency of a 230 V electric generator (gasoline powered).
I have a cheap but ok multimeter that does Hz but the reading is erratic (some 1 kHz...)
The reading on the mains ...
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Coaxial quality and frequency rating
Context
I aim to start playing with RF and the first thing I wish to do is some EMI tests.
I've been watching YouTube videos on the matter as you do, and I've seen plenty of people using SMA ...
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Clock divider/ multiplier ( 3/4, x6/4, x8/4) with CD4017s and CD4046
(UPDATED SCHEMATIC) I want to make a clock divider to add to a drum machine. I made this schematics, can anyone confirm it does what it s meant to (multiply the clock from the drum machine by 3/4,6/4,...
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Does locking a CPU frequency to a higher state (even OC) have any downsides?
I got into an argument with a friend that thinks generally is not a good idea to manually lock a CPU to a high frequency, or even overclocking by locking the frequency, in a stable scenario. His main ...
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Converter Switching Frequency
I am implementing a USB-to-system-to-battery charger (TI BQ25730 or TI BQ25723), which:
Converts USB voltage 5+ [V] to 4.2 [V] ...
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SMPS design formulas confusion
I was working on the SMPS but I have having trouble in getting a propper method to follow before designing an SMPS. I followed a video series but I didn't know where all those formulas came from as I ...
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NE555, 50% duty cycle at 110kHz
I want to get an NE555 chip with a 50% duty cycle to 108-110kHz in output.
I have already experimented with various online calculators and values. However, I never get the values that allow me to do ...
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If capacitors are frequency-dependent resistors, then what are inductors?
I was reading The Art of Electronics 3rd Edition, there it was saying "You can think of capacitors as frequency-dependent resistors."
So in terms of this description, what could inductors be?...
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unfamiliar notch filter configuration [duplicate]
This is a configuration of the notch filter that I saw in some design. It is very different from the Active Twin-T notch filter configs that show up on a quick google search. Any idea what is going on ...
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Make a tune-able resonant frequency
Using a long cable to a LC circuit reduced the resonant frequency, I reduced the inductance in order to increase the frequency; it worked. However the voltage amplitude decreased significantly. How ...
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Resonance inverters and pulsation frequency
I was reading one of the patents for the x-ray generator when I found a resonance inverter attached in front of the switching circuit. I understood how the system works but one statement written is ...
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How ideal should the clock input be for registers built out of 74HC chips?
I am a just starting my first build where a fully digital solution just isn't practical.
Basically I have an old laptop I want to give away but it doesn't have any backlight on the keyboard.
I have 2 ...
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Why don't we use the third harmonic in power transmission?
For some high power high voltage lines DC is used with the advantage that sinus wave AC obviously doesn't use the line to it's maximum capacity at all times. To correct this, we could use square wave ...
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Piezo sensor at resonance - equivalent model
piezo materials are commonly modelled with the BVD model
When the piezo is used as a sensor, they are commonly modelled as a current source in parallel with a capacitor because à external force ...
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PWM frequency for braking circuit
I am running a small DC car motor with PWM and I am using 20 kHz. This requires special op-amps with fast v/us times to get a proper square wave out to drive the MOSFETs even with drivers. I am trying ...
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Design of an antenna on a PCB card emitting between 1000 and 5000 Hz
I would like to create an antena on my PCB thanks to copper track. My antenna has to be a square like a coiled coil in order to emitt a magnetic field.
Is it possible to create an antenna like that ...
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Output load capacitance vs max input load capacitance
I am currently in the process of building a frequency divider circuit. To realize a lower frequency of 3.072 MHz. I use the: ECS-TXO-3225MV-122.8-TR
For frequency division and reduction I use D-...
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controlling power by AC frequency
I am working on circuit that will control a heat pad using a triac and microcontroller.
In order to reach minimal EMI noise rather than phase controll I am controlling the frequency.
schema:
As I ...
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Are RC /CR - Highpass filter the same?
I‘m quite new to electrical engineering and one of the tasks is to showcase and plot an CR high pass filter. I am familiar with RC HP filters but this is new to me. Just changing the order of the ...
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PVDF film to record high speed dynamic force
Do you know if TE Connectivity's PVDF films can be used as sensors for measuring high-speed impacts? The frequency range of the signal to be measured is between 3 kHz and 500 KHz. However, there is no ...
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Can we generate a frequency-dependent beams with uniform linear array?
I have some difficulties understand how can we generate frequency-dependent beams using unniform linear array. A paper that discusses this is the following: https://ieeexplore.ieee.org/stamp/stamp.jsp?...
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measuring frequency with opto-isolator
I have a circuit where 220VAC mains is stepped down by transformer to 48V and through an 5k1 resistor I'm activating optocoupler that drives a LED through a resistor on the other side. I am measuring ...
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Computation Doppler shift in ppm
I am computing Doppler shift for different flying platforms and after my first presentation, it was suggested to revise in ppm.
I compute always in Hz and have never heard even about this unit until ...
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'Best' topology to measure this weird sensor standard
I am developing an embedded solution to measure and record the analog signal from a PCB Piezotronics pressure sensor. Specifically the Model 124A21.
The sensor has some integrated circuitry to boost ...
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Motor frequency increase using a VFD
If I increase motor supply frequency to 70 Hz or more using a VFD, while maintaining the voltage at its rated value, will the current drawn by the motor increase?
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Creating a large number of crystal-stabilized pulse waves at precise frequencies
I intend to generate 22 separate 50% duty cycle pulse or square waves. The frequencies range from about 5 Hz to 350000 Hz and are all irrational numbers, so I would like as much precision as possible.
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THT resistor at high frequencies
Experimenting with radio frequencies (50-150 MHz) I found that parasitic inductance of resistor can cause problems.
Reading about resistors technologies (THT) seams that the parasitic inductance of a ...
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What is the resonant frequency?
I know the formula of resonance frequency for both series and parallel circuits. But when we have a circuit that is shown in the image below where the RESISTOR and INDUCTOR are in parallel and their ...
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How can I measure the frequency of multiple square waves?
I'm trying to evaluate the frequency of 18 independent sources of square waves in my system (the signals are generated independently as feedback.) Basically, I need to have a way to use one ...
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How to debug unexpected behavior on voltage-controlled oscillator PCBA?
I designed a circuit for a voltage-controlled oscillator (VCO) for use in a synth and had it fabricated and assembled as a PCBA. I got three assemblies back and while two behave exactly to spec (and ...
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