# Questions tagged [time]

Time cannot be created, but it can be measured by using common references. The oscillation of the cesium atom, or a pulsar, can be used in our lifespan, but neither one is steady forever. We can create 'instances' of time with tuning forks and electronic oscillators. By creating them we define them in terms of 'increments' of time. Those deemed to be laboratory grade become our reference devices for measuring time and frequency, the reciprocal of time.

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### Method for calculating time different between two acoustic signals using analog electonics [closed]

Think If we place two sensors at different places and record acoustic signal coming form certain direction. So, I want to find a method to calculate the time difference which two sensors detect the ...
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### What does it mean to have a settling time at 5% of final value?

I need to make my control system to have a tolerance of 5% in less than 0.5 seconds (settling time ts = 0.5s at 5%). My question is: does 5% mean the error band can be between these values in red (...
83 views

### Do I need RTC while I'm using NTP?

We know computer and another device like microcontroller is not accurate in ticking clock comparing to wall clock that using cesium atom. I heard RTC module is purpose to making accurate the ticking. ...
236 views

### Equation for total charge time of a capacitor in a half wave rectifier circuit

simulate this circuit – Schematic created using CircuitLab For the above circuit I want to know if there is a formula that can give me the capacitor voltage as a function of time. I'm not ...
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### Why don't the GPS equations account for receiver clock drift?

My basic understanding of GPS is that a network of at least four synchronized satellites send messages containing their locations and transmit times ($A_i, B_i, C_i$ and $t_i$) to an ...
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### Time domain reflectometry and resolution

Regarding the temporal (and consequently spatial) resolution of a TDR system, I've read from different sources that the maximum resolution achievable is half of the rising time of the input step ...
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If there is a power supply charging a capacitor (e.g. 4 μF) through a resistor (3.2 MΩ), the time constant can be calculated with the capacitance and resistance. If I, however, measured the voltage ...
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### Why do car blinkers seem to synchronize and then diverse from each other?

When I am on the road, the blinkers of other cars seem to sync together for a few clicks and then they diverse again. Is this just me seeing it wrong - so on fact they never sync - or is there some ...
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### Time synchronization of circuits in different places

How can i synchronize times of circuits placed quite far(a few hundreds of meters) from each other? I thought of using PPS signal from GPS receivers, but I'm not sure about this point: Are these PPS ...
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### Detecting pulses of one nanosecond length

As the title suggests, I want to detect extremely weak (~20mV) and short pulses: between 900ps and 1,5ns in length. I do not really care about the readout time or hold time after a pulse is detected. ...
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### Is there a way to convert a time delay into a sample delay?

I have been given a time delay of a signal and the sampling frequency, however, I am trying to calculate the delay in samples. My logic is: delay frequency divided by sampling frequency, however, this ...
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### Timing Diagram - HyperBus - HyperFlash - HyperRAM - RWDS - CLK - DQ

I'm trying to design an interface between an application processor and a HyperFlash memory from Cypress. Therefore, I'm trying to understand the timing diagram for RWDS and DQs relative to the CLK ...
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### Compute the total time required to take a photo

I'm in the computer sciences engineering field. For a project, I need to use a camera, take a photo, process it and take a decision and so on. It's a hard real time problem as we have timing ...
1 vote
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### Carry-select adder - Time calculation

a) Suppose a binary pick-up adder (carry-select) of 32-bits, comprising 4 sub-sections adders spreading carry of range 8 bits. Show the values ​​obtained internally in the circuit of this adder to ...
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### Memristor LTspice simulation not matching MATLAB or Python

I have been attempting to port a modified version of the Yakopcic memristor from Python/MATLAB to LTspice but have been running into issues with the results not being the same, as shown in the ...
90 views

### Viewing 100-200ns pulse on oscillocope

I've recently bought a Gould OS300 twin-beam 20MHz oscilloscope. I'm trying to view a 100ns to 200ns pulse, but I'm not sure I'm using the correct settings. The pulse voltage goes from 3.80V to 0V so ...
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### What does hₖ[n] mean here?

Is the impulse response different from the output y[n]? Is the input x[n] all the delta function at different values of n? From Signals and Systems by Robert Oppenheim, Linear Time Invariant systems
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### Is this the best way to make a timer auto-off feature for a CPU fan?

This circuit is outside of a PC simulate this circuit – Schematic created using CircuitLab I want to make a fan that shuts off after a preset time depending on the capacitor value. The button ...
1 vote
340 views

### How are system clock and oscillator frequency related?

My question is given a, for example, a quartz oscillator on a MCU board, how is the system clock generated? I'll break down this question into several parts below: I always have the impression that ...
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### Reliability of Sampling Rate vs Absolute Timestamps

I am building a system with multiple sensors and I want to sample the different sensors at different rates. For the sake of an example, I am using two MAX30102EFD-T sensors. One of the sensors I want ...
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### What is the uncertainty of the Analog Discovery oscilloscope?

I'm an electrical engineering student and I have to measure the Slew Rate of an opamp (and most importantly its uncertainty). I created a simple voltage follower circuit and I'm using the Analog ...
80 views

### State Space Clock Model & Control

I was hoping to get some help understanding a state space model that I have found in time and frequency literature. The literature pertains to a discrete-time model of a steered clock. A phase ...
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### How does the 4th satellite in GPS know the time offset?

Going through the working of GPS technology, I came to know that at least 4 satellites must be visible to solve for the location with considerable accuracy. Going through most of the resources, I can ...
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### What is a "discrete time controller"?

I'm reading a paper, and the first sentence is: Most dynamic systems are controlled by discrete time controllers What is a discrete time controller ? Thanks
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### How to use a CSV file from an oscilloscope for further analysis

I saved and opened this data from my oscilloscope: How to plot the real scale waveform data? Do I have to multiply it with vertical scale? And what about the time? What to do if I want to plot the ...
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### Best way to run current for certain amount of time

I have a circuit set up that requires around 5 Amps of current to run but I need it to only run for a specific amount of time. The circuit is activated when I press a button and I want some tool to ...
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### DIY reference clock jitter / Allan deviation measurement

I am considering doing some recreational timing. I have few OCXO's, GPSDO, Rb source - but no way to compare their stability / jitter. Majority of sources are around 10Mhz. Is there any DIY-friendly ...
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### How to sync time between two devices (<30m apart) with a sub milisecond accuracy? (think PTP)

So my task is to detect the source of banging in a metal tube (picture radiator pipe). The idea is to put two mics to the ends of the tube and measure time differences when they hear banging. The tube ...
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### Fourier Transform Time Scaling Property using f (frequency) or w (omega - angular frequency)

The time scaling property for a fourier transform is as follows: My book shows this property in terms of $f$; however, my instructor likes to use $\omega$. I have also seen this property written ...
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### A problem with designing a time register

I'm on a project where I need to design a time difference register. In a time register the time information is first converted to voltage, which is stored in a capacitor. Later, when we want the ...
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### Wireless Time Synchronization Project

I am part of a team project involving baseball where we would like to determine whether a runner stepped his foot on the base (first base, for example) before or after a fielder (the first baseman) ...
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### Inductor Voltage and Current After Switches Open and Close

I was given this problem where switch s1 and s2 are opening and closing at different times. I have already solved for the voltages and currents, but now I need to plot vL and iL at each time. My ...
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### Why is Δt constant in phase shift measurement?

I would like to ask for some help with phase shift plotting. To be precise, with time delay between two waveforms. I am measuring two currents using an oscilloscope. channel A (blue) is my current ...
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### The constant time value for an electronic device [closed]

i am working in a data science project that require certain information about electronic devices. So I know that for each electrical circuit there is a permanent regime and a transient regime and ...
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### Time interval quantized?

We have a capacitor fully charged with some voltage. At t=0 we can find the current. This current will change the voltage of the capacitor. However the information of the change of the voltage of the ...
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### time axis confusion in signals and systems

I am learning signals and systems and we are given a impulse response swhich is discrete and from -5 to +5 on X axis. I do not really understand that it has a negative part as everything starts from 0 ...
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### Calculate time energy is stored in capacitor

I have this problem: I've calculated A) to be 8 nJ, and my Vc(0) = 4 V and Vc(∞) = 0 V. I tried using the wc(t) = 1/2CVc^2 formula to calculate the time when the energy of the capacitor is 1 nJ. ...
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### How to discretize value like EDF ( or other electricity companie )

I make a solution using some automate like : A9MEM2050 ( Shneider ) ( and more advanced, so i have a lot a different value , that include rpm, psi, armonic, etc ...) Every automate send a value every ...
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### timestamp generator register location on Cortex-M4 (PSELCTRL CNTCR)

I am trying to find the location of the register where the timestamp generator can be enabled on a Cortex-M4 processor. In the CoreSight SoC Technical Reference Manual on page 3-210 it is mentioned ...
297 views

### Calculate power on time of a buzzer

I would like to use a 5v active piezo buzzer to beep for a second or two. When the relay is on NO the capacitor will charge from the dc source and when the relay is on NC the capacitor will discharge ...
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### Are consumer systems able to measure nanosecond timings?

Following the theft of my brother's car (a modern Audi Q-something), I got interested in how contemporary cars are protected. The authentication of the key to the car is dreadful (I work in ...
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### PPS Timer on STM32

The MCU used is a STM32F042 which is clocked by an OCXO oscillator (Abracon 10 MHz - 20 ppb). The subject of this thread is to get the best accuracy on one PPS Timer. For my application, I need to ...
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### Time Domain Analysis with Vector Network Analyzer

I have done some measurements with a VNA in time domain (by using the transform operation of the instrument). Precisely, I have selected the measurement of S11 (reflection coefficient at port 1 of the ...
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### How do I calculate the capacity of a capacitor using measurements of an experiment?

I build this circuit in an experiment During the experiment I got these readings: ...
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### Is charge batteries in series faster than in parallel?

I would like to know if charging 7 lithium-ion batteries in series with BMS 7S are faster than simply charge them in parallel. Please for your advice, thank you!
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### How to generate time delay when input frequency is high?

Im trying to generate time delay for my gate drivers for a project im working on. But the issue is at lower frequencies my circuit works fine, as I ramp up the frequency (upto 250Khz) the output goes ...
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### Current when switching on with inductance. Role of Reactance?

When switching on the current through a coil it can be described as: $I(t) = \frac{U}{R} \cdot (1 - e^{(-x\cdot R/L)})$ For a sinusiodal current the complex resistance for a circuit with ...
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### NTP Time calculating

I have this code and i use in my device. ...