# Questions tagged [waveform]

The shape of a value (usually voltage) when graphed over time.

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### Why is Zener avalanche noise saw tooth shaped?

I have the following schematic of a Zener based noise source:- simulate this circuit – Schematic created using CircuitLab When built, an oscilloscope reveals a saw tooth noise signal at the "...
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### OP amps distort sine wave

I am creating a simple circuit in order to amplify the signal from an electret microphone and then add a 2.5V bias to the signal. The problem I'm having is that the signal from the mic is distorted as ...
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### What does the radiation from an antenna look like?

Just out of curiosity, I searched for antenna on Google Images, and what usually shows is something like this. So I really thought that an antenna radiates in a circular and equal pattern. But as I ...
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### What is causing this distortion of a pulse wave when recorded to a reel-to-reel tape?

I'm currently trying to record a pulse train used as a tempo clock for music instruments (e.g. output of Korg Volca 'sync out') onto my Fostex M-8 reel-to-reel recorder, with the aims to then ...
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### Why is signal on XTAL1 and XTAL2 a sine wave (not square)?

I have a basic implementation with a crystal feeding XTAL1 and XTAL2 on a processor (similar to below). When I look at the signal on XTAL1 and XTAL2 they are sine waves. Shouldn't they be square ...
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### Square Wave input into Transformer

Can a square wave generated using an astable NE555 be used as input of a transformer instead of AC? Say, I generate a square wave of 60Hz using NE555 and a 24V at 6A supply and feed it into a ...
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### How do you shift a square wave down?

I have a square wave the oscilates at 25khz from 0 to 30v. I would like it to oscillate from -15v to +15v. Is there a SUPER DUPER SIMPLE circuit to do this? Keep in mind it's going up and down at ...
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### Why does putting resistors between Vcc/SDA & Vcc/SCL in I2C result in a square wave?

I'm trying to understand why placing resistors between Vcc and the data/clock lines helps my waveform be square, when I'm communicating between Arduino and an EEPROM chip. If resistors are not placed ...
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### What protocol is this waveform?

I'm trying to reverse engineer a communication line between two components. However for debugging I'm connecting to only one of them, powering it up and looking at the signal. I have no experience ...
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### If a square wave has infinite bandwidth, how can we see it on an oscilloscope?

If a square wave requires infinite bandwidth how can we display it on oscilloscopes? Link: Oscilloscope fundamentals.
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### Is there a spice directive to export waveform data in LTspice?

http://www.linear.com/solutions/1815 The above web-page explains how to export the waveform data to a text file. You basically run the LTspice simulation, clicking on the waveform window, go to ...
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### Voltage spikes in triangular waveform generator circuit using LM324 op amp

I recently made a triangular waveform generator circuit using LM324 op amp. But the output of the generator had some sort of periodic spikes in it. However I was able to suppress the spikes by ...
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### What units are kpts?

I am parsing data from a Siglent SDS2000X oscilloscope. The first chunk (0x00 - 0x003) is for wave_length. The data sheet ...
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### What could be generating this waveform in an EMC Compliance test?

We are having trouble with a CISPR-11 (EN55011) Radiated Emissions Class B compliance test in one of our solutions. The troubling part of it is basically an industrial motherboard (with a commercial ...
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### Operating principles of a sawtooth wave generator bootstrap circuit

In one of my assignments, I was asked to explain the working principles of the sawtooth wave generator shown below. The input voltage is a spiked waveform obtained from a differentiator circuit. I ...
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### Peak to Peak vs. Amplitude

For a sine wave, Amplitude is the fluctuation or displacement of the wave from its mean value. Peak-to-peak (pk-pk) is the difference between the maximum positive and the maximum negative amplitudes ...
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### Why do we use the terms AC and DC if they have nothing to do with current?

It seems archaic, maybe that we use the term AC (alternating current) and DC (direct current) to talk about power systems. After all, it is the voltage waveform we're usually referring to. In my first ...
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### How to Calculate the average of a Square Wave?

I could not figure how to calculate the average of a square wave. Consider a square wave of +5V from time 0 to 6 sec and -3V from 6 to 10 sec. On integrating from time 0 to 6 the average: 3.0V On ...
858 views

### Why IR remote waveform is a saw-tooth or am I measuring it wrong

The measurement circuit is as follows: simulate this circuit – Schematic created using CircuitLab The waveform looks like this in my measurement: Is this because I'm measuring it wrong and ...
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### What is the reason for the "back porch" current requirement on an SCR gate driver?

I am studying SCR gate drivers at the moment and I would like to understand their fundamentals. Looking at a SCR datasheet (for example, this one section 7 or this application note fig 6 p4,) one see ...
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### Using Oscilloscope So That Nothing Blows Up

I want to see the input current waveform of an LED T8 18W. An EM ballast is purposely placed in series with the lamp. I don't have a power analyzer. What's available is a GDS-2102 oscilloscope. So I ...
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### Why am I getting a half-wave rectified output when i am using a full-wave rectifier?

I have recently gotten back into electronics and have access to a lab with a signal generator and oscilloscope. I have been trying to teach myself how to use this equipment by building small and ...
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### Working of Hex Schmitt−Trigger Inverter as a Sawtooth and Square Wave Producer

Can someone explain how a Schmitt Inverter can behave as a Sawtooth (on pin 1) and a Square wave (on pin 2) as produced in a circuit where we have a Capacitor between pin 1 and GND, and a resistor ...
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### Capturing mains AC waveform with audio recording device

I'm wondering how practical (read: safe) it would be to use an audio capture device to "record" a mains AC signal for the purposes of monitoring the characteristics of the AC sine wave. I am ...
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### LED not outputting square wave signal

I'm working on a sensor similar to an oximeter that measures light attenuation through a medium. I have an LED on one side, and an IC photodiode with on-chip transimpedance amplifier (OPT101) on the ...
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### What is the source of this shape on my USB eye diagram?

I have designed a USB device around an STM32F105. It is USB 2.0 Full Speed CDC device configured as a Virtual COM Port using ST's USB Library. It uses the STM32's built-in PHY, and runs at 12 Mbps. ...
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### Square wave generator without op-amp

I am trying to make a square wave generator but don't have an op-amp nor the PNP transistor to do it. Is there any way that works? I have tried using this one: simulate this circuit – Schematic ...
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### Waveform result of an equation

I have this waveform and I would like to have the Y. I know that the equation is Y = D' + E' + F'. Where it has ' it means NOT. ...
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### Improving waveform shape in discrete Pierce oscillator with Schmitt trigger output

I am making a simple clock source using discrete Pierce oscillator with its output attached to high speed Schmitt trigger buffer to get square wave in the final output. I got the circuit for the ...
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### How to store more waveform after trigger and less before?

I have a Rigol DS1074Z and can't figure out how to lower the time the scope spends pre-sampling to open up more memory for the actual data I want to see. Here is a nice image that will hopefully ...
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### Circuit find IB, IC and VCE?

I'm asked to find IB, IC and VCE. This is my answer: I wonder if my answer is true are not. VCE Value is negative, is this true or not?
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### Shift Registers Controlling Seven-Segment Display without a Latch?

I'm restoring a Model H Skee-Ball machine, and these old models have a bunch of hardcoded settings and unreliable switch detection, so I want to replace the main control circuitry with something ...
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### Want Square Waves based on Injection Timing of 4-Stroke Engine

Recently, I am working on ECU of CNG Auto Rickshaw having 4 Stroke Engine. Here, Image shows the Engine of Auto Rickshaw. I have already taken reading of MAP, TPS and RPM. And now I am working on ...
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### Is it possible to change Arduino Nano sine wave frequency without using PWM? [closed]

I have a program that generates a sine wave (array with predefined 8 bit values) on an Arduino Nano. ...
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### Could sawtooth waveform be optimal for transformer input?

All the transformer theory I have reviewed uses sinusoidal waveforms, and concludes that a true sinusoidal input is optimal. But I'm wondering whether a sawtooth waveform would actually be optimal in ...
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### Op-amp square wave to triangle wave converter not working as expected

A follow-up to a similar question from yesterday since the problem I've run into has differed enough to warrant something more than an edit. I have built an integrator to act as a 5V 32Hz square wave ...
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### SPI waveform on Raspberry Pi is not clean, and I'm wondering why

I have a Raspberry Pi Zero Wireless and I wish to connect it to an FPGA via SPI. I have done some SPI tests with my 100 MHz oscilloscope and see the images shown below. The Raspberry Pi ...
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### Is it normal for a square signal to change into a sine shape at high frequencies?

The signal generator outputs a square wave into an LED which emits light onto a photodiode. The photodiode is connected in a TIA circuit and then output is displayed on an oscilloscope. The output ...
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### Smooth wave plotting using 3 inch thermal printer [closed]

I am interfacing 3 inch Fujitsu thermal printer (FTP-638MCL103) with STM32. Character printing is working fine. I am struggling to print smooth sine waves generated from a function generator. I want ...
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### Square wave to triangle wave converter using Op-Amp not working

I have built an integrator to act as a 5V 30Hz square wave to triangle wave converter. My output currently looks like this. I am unsure why. The value of the triangle wave amplitude, according to ...
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### Export Modelsim waveforms as image for printing

I want to export the Modelsim waveforms of my simulated design in a form where they can look decent when printed. To be more specific, without the black background, in a vector format preferably. Not ...
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### Waveform generation on FPGA

Can anyone give me an idea on how to generate this RF waveform on FPGA? I already have the I(cos) and Q(sin) signals generated just need a guide to produce this weird shaped pulse. Edit: This is the ...
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### Quality of a square wave?

For an assignment I was asked to evaluate the quality of a square wave I had generated with an op-amp. After spending quite a bit of time searching I have yet to be able to find a definition of the ...
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### How can I generate this waveform?

I am trying to generate this waveform: basically a ramped square wave with a maximum frequency of 1KHz. My first thought was to use the DAC pin of a microcontroller, but are there any ICs that can do ...
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### Why does the diode current waveform look like this in a full-wave rectifier?

The oscilloscope trace below shows the output waveforms for the diode current (yellow) and the load voltage (blue) for a single phase full-wave uncontrolled bridge rectifier. The load attached to the ...
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### Can a triac which is driven by another triac be used for switching AC continuously?

MOC3041, BTA06 I am considering cascading two triacs like this in order to make a solid state relay. I'm not going to control the phase angle of the voltage on load as done in dimmers. I only want to ...
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### 1.2/50 us Combinational Wave Generator (Surge Test) Simulation - Help Needed

I am looking for assistance in editing my LTspice simulation for the design mentioned in the title. I have provided the design and output (open + short circuit) expectations (First two screenshots), ...
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### Understanding digital filters, specifically their effects on time domain information, how to preserve the waveform of a signal being filtered?

According to Steven W. Smith, in his book: The Scientist and Engineer's Guide to Digital Signal Processing, when designing a digital filter, "Good performance in the time domain results in poor ...
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