Questions tagged [wien-bridge]
Anything related to Wien bridge circuits. A Wien bridge is a particular bridge circuit configuration in which two sides of the bridge are purely resistive, whereas the other two are made up by resistors in parallel with capacitors. Wien bridges are commonly used in linear oscillators for producing sinusoidal signals.
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Doubts about the Stable Amplitude of Diodes in Wien Bridge Oscillator
Recently, I have been studying theWien Bridge Oscillator and I am a bit confused about the process of the diode automatically stabilizing its amplitude. The following diagram is used for circuit ...
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Wien bridge oscillates at 6x expected freq and amplitude oscillates too
A while ago I made a Wien bridge oscillator to go from ~500 Hz to ~1 MHz, using an NE5532 opamp and stabilizing amplitude with the typical opposing diodes method. Worked fine, but the output was too ...
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How to control the amplitude of a Wien-bridge oscillator?
I am trying to design a Wien-bridge oscillator and understood the basic working principle of it. Now I got to the point where I want to add a system which would make the gain >3 during startup and &...
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RC oscillator with Wien bridge and JFET amplitude stabilizaton
I need to make an RC oscillator with a Wien bridge and JFET amplitude stabilization, I have a schematic, but no formulas on how to calculate the values. I tried to look around the internet, but found ...
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Why doesn't this Wien Bridge oscillator work?
See the circuit. I am running this from a 24 V supply. I need it to oscillate at about 700 Hz.
Does anybody see anything wrong with the circuit? I have spent about 3 days trying to figure it out, but ...
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My Wien bridge oscillator doesn't work, what could the problem be?
I suspect I am making a probe connection mistake, but couldn't figure it out.
The circuit works fine in LTSpice but I don't get anything in a real experiment.
What might be the problem?
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Negative Oscillating Signal with Op-Amp?
I am trying to design a Wein Bridge oscillator that oscillates with frequency 1.5 kHz using LM741 Op-Amp. I simulate it in LT-Spice and obtained sinusoidal oscillation going both positive and negative....
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Frequency of square wave generated by Wien bridge oscillator
I have designed the wien bridge oscillator circuit for 20Hz square wave generation. It gives a 20Hz sinusoid as output when I keep the non-inverting amplifier gain 3V/V. But when the non-inverting ...
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Dual op-amp Wien bridge oscillator queries
I'm trying to understand a Wien Bridge oscillator circuit as published in Elektor 7/1987 on page 63, and I'm getting kind of frustrated. I've reviewed plenty of theory in an attempt to revive my BEng ...
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Wien Bridge Oscillator: Why does equating the real part to 0 give the gain equation?
I am learning about Wien bridge oscillators. Following Experiment No. 9: WIEN BRIDGE OSCILLATOR USING OPAMP, they use the following schematic:
They then arrive at the following equation half-way down ...
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Wien bridge oscillator frequency
Question from Microelectronic Circuits by Sedra and Smith, Section 17.2: Op Amp–RC Oscillator Circuits:
17.10 For the Wien-bridge oscillator of Fig. 17.4, let
the closed-loop amplifier (formed by the ...
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What is the purpose of the anti-parallel diodes in this Wien Bridge oscilator circuit?
In the following op-amp circuit:
Rf here is replaced by the following:
What do the anti-parallel diodes here serve? This is a Wien Bridge oscillator circuit and I am showing only the negative ...
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Trying to obtain a voltage gain equal to 3 without an op-amp
I'm a beginner in electronics and currently, I am trying to design a Wien bridge oscillator. I've read documents about oscillators. For now I am stuck at trying to design the amplifier, without using ...
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How to make sure this oscillator will be stable?
In my textbook, the Wien-Bridge oscillator and the Twin-T oscillator needs a tungsten lamp as the self-adjusting resistance:
The lead-lag circuit connected to noninverting input has a gain of 1/3 on ...
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Wien Bridge Oscillator using OpAmp(LM386) works in simulation, but doesn't work in Breadboard?
This is a simulation of the circuit in multisim. It is a Wien bridge oscillator circuit, tuned at 1844Hz. I am mostly interested in generating sound of that frequency. It seems to work here in ...
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Make old telephone ring
I recently found one of those old rotary dial telephones in my garage and amazingly it still is fully functional (I tested it by hooking it to the phone line). As I have no use for it as a telephone ...
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How is an incandescent light bulb used for gain stabilisation?
If a circuit like the Wien bridge oscillator below uses an incandescent bulb for automatic gain control, how does this actually vary the gain?
I know that the resistance of the bulb increases as the ...
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The Wien Bridge Oscillator
The question is that: How could you make a Wien bridge tune to different frequencies?
Since the frequency is depended on the value of the resistor and capacitor we should use a variable resistor and ...
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Diode and capacitor at the Wien Bridge Oscillator
The circuit below represents the JFET stabilized Wien-bridge oscillator.
we add another diode in the circuit. Shown in the picture below:
The questions are:
Before adding the second the diode the ...
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Is the Wien Bridge oscillator essentially a resonant filter?
According to chapter 21 of Electronic Principles(8th edition), the Wien bridge oscillator uses the Johnson-Nyquist noise from one of the resistors as the startup voltage. It selects for a desired ...
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Current across Wien bridge
I am trying to answer the question
If you connect a detector between Va and Vb, knowing that the frequency to which the bridge is balanced is 6820,58Hz, what is the current that passes through the ...
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Wien bridge oscillator amplitude stability methods
I have read things about tungsten bulbs and its thermally controlled resistance. But what can I use for an electronics project will be builded on a breadboard. I searched for tungsten bulbs and all ...
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Sinusoidal waveform generator from DC
I am working on a project which requires me to create some sinusoidal signals at specific frequencies using a DC battery as the only power input. And I also want to tune the amplitude of the output ...
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wien bridge oscillator transfer function
I am trying to calculate the transfer function of a wien bridge oscillator but there is something wrong in my calculations.
In the picture below there are my results from this calcultation. I am ...
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JFET stabilised wien bridge component ratios
I find myself in need of a sine wave oscillator and have decided on the wien bridge. I have followed all the tutorials but have a few questions that do not seem to be answered elsewhere.
Firstly, I ...
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Transistor differential wein bridge oscillator wrong frequency
So I have created the attached Wien bridge oscillator using a transistor differential amplifier, the Negative gain is controlled using a potentiometer, center tapped and yes I understand that in the ...
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Vary the Vpp of sinusoidal oscillator
For an assignment I have to create a sinusoidal oscillator with 5 Vpp (centered around 0 V) oscillating at 10.0 kHz. The oscillator works as expected, at the right frequency, but the voltage needs to ...
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Electronic metronome Wien oscillator
I've got to analyze an electronic metronome schematic and I'm having trouble understanding how the oscillator in this schematic really works.
I believe it's a Wien oscillator with variable output ...
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Measuring a varying capacitance using the Wien bridge
I am going to make a capacitive soil moisture sensor. The principal that I'm going to use is the change of capacitance of the soil with moisture. What I'm going to do is make a capacitor that would be ...
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Whats the equation to calculate the Vo-w and Vp amplitude of this Wien Bridge oscillator?
Im trying to find the equation to the amplitude of this wien bridge, if you could help me that would be awesome
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Wien Bridge Oscillator in Multsim Values
I am trying to build a Wien Bridge Oscillator in Multisim that has a frequency of 3.6 kHz. However my graph is very distorted and I'm guessing its because of the op amp component values. Does anyone ...
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Why spectrum analyzer ruined my oscillator's output?
I have been tried to investigate and fix this problem by myself. I however cannot find the solution. Please give me some advises.
I used 3 traditional oscillator circuits with opamps (Wien bridge, ...
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Troubleshooting wien bridge oscillator circuit with 741 op amp
I built the standard Wien bridge oscillator circuit using the UA741CN op amp IC, however I am not getting any oscillation.
I am powering this circuit with two 9V batteries. I'm using the values R1=...
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How to add a phase shifter to a Wien bridge oscillator
I need to add a variable phase shift circuit to my Wien Oscillator, I have done some research, but have only found phase shift oscillators made with 3 RC stages that generate a 180º shift. However, I ...
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How to decouple a negative feedback loop in DC?
My question is open ended, but I provided an example to explain the question better. R19 and R8 in the middle of the pic form a negative feedback loop. They set the gain of the amplifier.
I need to ...
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Trying to build a Wien bridge oscillator, but can't make the oscillations work.
I built this circuit to have oscillations between 20kHz to 30kHz. Unfortunately the oscillations come out very tiny and very irregular.
What should I modify or add and why to make the oscillations ...
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JFET Burn Out in Wien Bridge Oscillator
I have a simple Wien Bridge Oscillator (with JFET gain control) circuit pictured below. This circuit works as expected at lower voltages (+/-9 V), but I am running into some problems with higher ...
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Problems Building Variable Frequency Wien-Bridge Oscillator
I have been doing some experiments with Wien-Bridge Sine Wave Oscillators, specifically trying to make one where frequency can be controlled via a single knob, using a dual ganged potentiometer. I am ...
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Wien Bridge Oscillator Resonant Frequency cannot reached!
I am so bothered by the output frequency of my Wien Bridge oscillator because I cannot reached the resonant frequency which is given by
f=1/2iπRC.
FOR EXAMPLE:
R = R1 = R2 = 1.5kΩ
C = C1 = C2 = ...
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Wien Bridge Oscillator - LT Super Low Distortion Variable Sine Wave Oscillator Debug
I have been setting up a low distortion sine wave generator based on this design from LT (http://www.linear.com/solutions/1623):
For resistors R1 and R2 I am using a ganged pot so that both change ...
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Great Voltage Stable Oscillator
i'm want to produce an AC signal an +-3.3V (or 3.3v-0) voltage supply with a small frequency around 1kHz-2KHz and a low output voltage too(200mV,for example), where the frequency stability is not ...
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How sine wave is generated in wien bridge oscillator? [closed]
It is known that the initial feedback signal is developed from the noise in the resitors and the transients of the power supply. The question here is : why the waveform at the output is sine wave ...
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Wien Bridge Oscillator with LM358
I am constructing 10kHz , 30kHz and 50kHz sine waves using wien bridge oscillator design with LM358 OP-Amp. I have a few problems with the circuits that i could not figure out. Thank you for all your ...
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Effect on opamp lead length for non-functional wien bridge oscillator
I've built two diode stabilised variable frequency wien bridge oscillator circuits according to this schematic:
(source). Both are on the same stripboard and connect to a single LM324.
One of the ...
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Wien bridge oscillator circuit doesn't work
I've connected the circuit of Fig 3.4.6 in this link which is shown below:
Here is the circuit that I've connected:
Where in my circuit:
R3 = 100 kOhm
R4 = 47 kOhm
R1 = R2 = 5.1 kOhm
C1 = C2 = 100 ...
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How can I build a dual potentiometer?
I am about to build a wien bridge oscillator circuit which is shown in the figure below:
However, I need a dual potentiometer to do so, because the resistors VR1a and VR1b must have the same value ...
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Transistor Based Wien Bridge Oscillator
I've been studying the schematic for this RLC Bridge from Heathkit (IB-5281). The full pdf can be found here (search for the part number): http://www.vintage-radio.info/heathkit.
The circuit ...
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Wien bridge sinusoidal oscillator
simulate this circuit – Schematic created using CircuitLab
I would check that in the Wien bridge sinusoidal oscillator the gain A_V=1+(R5+R4)/R3) is actually A_V=3 as the Barkhausen stability ...
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How to calculate the amplitude of a Wien Bridge Oscillator? [closed]
How do I calculate the amplitude of the waveform that is created with this Wien Bridge Oscillator? My scope measurement shows 1V. My LTSpice shows ~.8V.
Thank you.
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Problem in wien bridge oscillator
I have put up a circuit for Wien bridge oscillator using 741 op amp, with R= 390 ohm and C = 2.2nF, for operation around 200 khz ( gain is 4). However, it did not work so I switched the resistor in ...
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