Questions tagged [frequency]
How many times something happens per second, measured in Hz (hertz).
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How can I compare these two frequencies?
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 does a PLL PFD produce a high frequency?
I am going to work with a PLL and a VCO.
I have read and understood the basic procedure in which the charge pump works. I understood that say, when the reference signal (or the divided signal) is up ...
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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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How to calculate far field distance from an antenna
I understand the formula for calculating the far field distance from an antenna is:
Distance = (2D2)/λ
Is the D in the above equation the length of the antenna under test (antenna under test is a ...
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How to calculate PWM duty cycle to compensate for different piezo sounder response at different frequencies?
How to calculate PWM duty cycle to compensate for different piezo sounder response at different frequencies?
I have a piezo sounder, and the datasheet informs me that I will get the following ...
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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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sr-t500 walkie-talkie module [closed]
I have the sr-t500 walkie-talkie module.
Everything works fine, but the sound is not sent through the microphone!
I tried replacing the microphone, but there was no change.
Does anyone have ideas ...
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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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Maximum input frequency of 74HC Logic gates
I have a clock that is running at 25.175MHz I want to run that signal through some basic logic gates from the 74HC series.
I have looked on the datasheet for the 74HC08 (AND Gate), I can't seem to ...
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Why does the \$ Q\$-factor depend on the resonant frequency?
The \$Q\$-factor is defined as $$Q=\frac{\omega_{0}}{\Delta \omega},$$
where \$ \Delta \omega\$ is the bandwidth around the resonant frequency \$ \omega
_{0}\$. For a series RLC circuit, $$\Delta \...
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Calculate total harmonic distortion
I have the following problem.
MY ATTEMPT
I found the formula for the total harmonic distortion to be this:
\$THD = \frac{\sqrt{V_2^2+V_3^2+V_4^2+V_5^2+...}}{V_1} \$, where the subscript denotes the ...
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STM32 timer settings changing
I'm using an STM32F407VG. I created a 28 kHz square wave by using timer PWM generation. When I look at the oscilloscope, I can see it clearly. I'm having trouble changing the frequency of the PWM ...
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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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how to find the frequency of this nonperiodic composite signal?
I'm new to electrical engineering, sorry if my question sound dumb. Below is a nonperiodic composite signal plot:
As you can see this is a nonperiodic composite signal in 1s and I know that if the ...
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How would this circuit work?
This is a frequency doubler from a graphene frequency doubler paper if anyone know the working with substituting a normal transistor instead of a GFET?
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Why does short band (high frequency) radio travel longer than low frequency?
In physics, we are taught that longer wavelength (lower frequency) have a lower attenuation in air, and thus is able to travel longer distances.
However, when talking about radio channels, short wave (...
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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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STM32F103C8 SPI1 clock frequency too low (~32kHz)
I am trying to program SPI1 on STM32F103C8T6 (black pill board).
I have configured it as follows:
...
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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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FSK demodulation with LM565
On the Internet I found FSK demodulation connection diagram with LM565 . And I'm trying to connect up it in Qucs. At the output of the whole schema I get unclear result.
In my previous topic we were ...
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How can I calculate the input power at a given frequency for a PWM motor?
Is it possible to calculate what input power (watts) is needed to run a given PWM at a certain line frequency (hertz)?
I have all the motor parameters, I know:
P-nom, nominal power, kW
U-nom, nominal ...
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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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Unable to measure frequency response of a Wien bridge oscillator with Bode plot
I'm unable to get the Bode plot to work with this Wien bridge oscillator circuit.
Is there something wrong with my configuration, or does the Bode plot not work without an external signal source?
I ...
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Will capacitor in high pass filter pass high frequencies while it is blocking low frequencies?
I thought that capacitors will only act as a conductor while is is being charged and once fully charged it will not conduct any more. I know that current does not actually pass through the capacitor ...
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De-rating / Re-rating criteria/theory for frequency in circuit breakers
I'm trying to spec a circuit breaker for a system that will be performing in the 3kHz range, and am not finding much info on how to calculate a new rating based on frequencies in this range (where ...
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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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How do I calculate limit frequency of the attenuator circuit?
Calculate the limit frequency \$fg\$ of the attenuation \$v_u =\frac{ u_a} { u_e}\$ at the current source I (for the value given in example), so that for \$f>> fg\$ exist ideal behavior.
Note: ...
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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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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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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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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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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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1GHz digital oscilloscope with 50MS/s sample rate
Can someone please explain to me why can't I measure a non-periodic pulse signal \$T_r=1ns\$, with a digital oscilloscope \$1GHz\$ with a sample rate of \$50MS/s\$?
I may have to solve similar ...
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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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What frequency stability crystal do we need?
We're designing a simple digital clock and using a 32.768 kHz crystal with a frequency stability of 20 ppm (standard off-the-shelf SMT).
We're finding the clock is running fast by about 2.5 minutes ...
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Frequency upconversion from 1 to 100 MHz for FM transmitter
I'm trying to build an FM transmitter like pifm but using the ESP32. I can generate an FM signal at the DAC output of the ESP32 with a carrier frequency of 1 MHz and a deviation of 25 kHz, but in ...
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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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How to calculate the safe AC frequency at high Voltages?
If someone wanted to build some kind of machine which produces HUGE and completely safe electric arcs, how would you calculate the frequency of the AC current in relation to Volt to make it safe?
Why ...
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Why do power grids tend to operate at low frequencies like 60 Hz and 50 Hz?
I understand that a two-pole AC generator has to rotate at 3600 rpm (60 Hz USA) in order to maintain a 60 Hz frequency and higher frequencies would require these generators to spin even faster which ...
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Does the antenna length differ between transmitter and receiver?
I bought this 433Mhz transmitter/receiver that has two different antennas included. I managed to solder the receiver antenna to the transmitter. Is this a problem?
Shouldn't they have the same length ...
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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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Generator frequency control
We are trying to run an AC generator on an RV for a customer. On an RV as you drive the engine RPM goes up and down. As I understand it, that would change the outlut AC frequency.
Is there an ...
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