A device or circuit that generates an AC signal at a certain frequency.

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3
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3answers
98 views

how does current go to infinity in an ideal LC circuit at resonance?

Consider an ideal LC series circuit, excited by a sinusoidal source at resonant frequency. Assume zero initial conditions, for capacitor voltage and inductor current. simulate this circuit ...
3
votes
1answer
48 views

how to select capacitor for a crystal oscillator

Here is a 32 MHz crystal from one of TI's reference design The BOM list defines the crystal as ...
0
votes
1answer
94 views

Oscillator problem

I was designing an oscillator for HF range. Although both the circuits are same, the first circuit doesnt work while the second one does, despite the fact that the varicap used has 17 pF at 20 V. ( ...
1
vote
1answer
31 views

pic16f628a internal oscillator setup error undefined symbol “INTOSC”

I want to set internal oscillator for pic16f628a, according to datasheet page 96, I have to set FOSC_INTOSC, but I get this error ...
2
votes
1answer
55 views

What is the conductance of this LC tank?

So, I start with total conductance: $$ G_{TK} = \frac{1}{\frac{1}{j\omega C}+ 2R_C} + \frac{1}{j\omega L + R_L} $$ Then, when I take only the real part of this expression in order to know the ...
-1
votes
2answers
71 views

Why Inductor reactance 180 ohms?

Why is the inductor reactance 180 ohms for designing Voltage controlled Oscillators ( or oscillators maybe ?) I came across a few resources for designing oscillators, colpitts and hartley ...
2
votes
1answer
204 views

Why does this regenerative receiver not just turn into an oscillator?

I'm trying my hand at making a radio transmitter and receiver and I'm not sure exactly how this receiver works. I understand its a continuous wave receiver which is good for on/off transmission. I'm ...
0
votes
0answers
38 views

Crystal Oscillator Output Amplification

I have a HCMOS Crystal Oscillator at 50 Mhz (DataSheet). With an ac coupling and pi network I generate a sine wave with 50 ohm output impedance. In standart bjt oscillator circuits, one need to make ...
16
votes
3answers
2k views

How does a Crystal work?

Specifically, a 2pin and 4pin quartz crystal oscillator. What I know: current is applied and the crystal oscillates in order to provide an oscillating signal. What I want to know: How does the ...
2
votes
2answers
77 views

Can oscillators be made from a single supply?

Oscillators such as a Wein-bridge sinusoid or a square wave Schmitt trigger oscillator. Is it possible to bias these so they oscillate above 0V?
1
vote
0answers
27 views

Microwave Oscillator: Both Ports Unstable?

I'm just wondering, for microwave oscillators, I think both ports need to be in the transistor's unstable region. What would happen if just one port were in the unstable region and the other in the ...
1
vote
1answer
62 views

Proper oscillator for CPLD

I plan to use KC5032A40 as a clock source for CoolRunnerXPLA3 256. I power it with 3.3V and interface it as suggested: I perform the measurement at the Test Point and do not add any CL capacitance, ...
4
votes
2answers
92 views

Why use asymmetrical capacitor values for crystal?

Are there any circumstances where you would want asymetrical load capacitors on a crystal? I came across this schematic in the documentation for an NXP UART. It looks just wrong to me. Can anyone tell ...
0
votes
2answers
56 views

Ring oscillator frequency

According to Barkhausen's criteria, for oscillation the feedback should be made after phase difference of 2pi and gain has to be >=1. Now when I consider a ring oscillator if 2 inverters are ...
3
votes
1answer
214 views

Crystal oscillator wave shape?

I hooked up a crystal oscillator (4 pins) to Vcc + Gnd and observed the generated waveform using my scope. I think everyone will agree the waveform shown is very distorted and I am not sure why. Any ...
0
votes
2answers
103 views

Crystal Oscillator design with no data sheet

I am a newbie to circuit design and I need a 50MHz clock. I went to a local electronics store and got a 2-pin radial Quartz crystal. I do not have a data sheet for this. The only markings for the part ...
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votes
2answers
63 views

Analyzing clock oscillator using timing diagram

In a recent examination a friend of mine was asked to analyze and find the frequency of oscillation of a clock oscillator using timing diagram as shown below: Can someone give me directions as how ...
0
votes
1answer
76 views

connecting oscillators in parallel to increase current

I am trying to power an alternating current coil, and was wondering if I can connect the output from transistor oscillators in parallel to increase the current, like you can with batteries. I don't ...
0
votes
1answer
100 views

Correct 4-pin Oscillator connections

I'm looking for the correct way to connect a 4-pin oscillator to a PIC24F. I have seen diagrams like the one below, but it seems that this connection is only for crystals and not crystal oscillators. ...
1
vote
2answers
131 views

What do Capacitors do in a System with a Speaker?

I made a circuit based on a diagram from my physics teacher. The circuit has a 555 chip connected to seven wires that make up a circuit. The circuit includes a photocell resistor that acts as a ...
3
votes
1answer
57 views

Audio oscillator cross-talk on small synth project

I am making a small 9V battery powered synthesizer with a square wave oscillator built around a 40106b Schmitt trigger (reference: http://richdecibels.com/blog/?p=11) and a few other components, one ...
0
votes
1answer
59 views

A voltage-controlled oscillator? [closed]

I need to identify a circuit from its function. So, here is the block (called OCT): I only know that the components are organized in the following manner: Where INT is an integrator, COMP is a ...
4
votes
2answers
415 views

What components are needed for a 20MHz square wave clock?

I would like to create a 20Mhz clock that generates a square wave for the home-brew Z80 computer I' making. I already have several 20MHz crystal oscillators but am at a loss when it comes to circuit ...
2
votes
3answers
151 views

RC phase shift oscillator : how to give positive feedback?

why is negative feedback given in a rc shift oscillator although a oscillator requires a positive feedback? as shown in this figure. And as shown here positive feedback is given by connecting the ...
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votes
1answer
42 views

Buffers in oscillators

Simple question. Consider positive feedback electronic oscillators. Imagine the amplifier I wanna use has an input impedance which is non infinite. Is it a buffer always meant to be put between the ...
1
vote
1answer
44 views

DC Air pump oscillator - square vs sine

I have an air pump that currently runs on AC, but I want to run on a solar/battery system that's 12V DC. The internals of the pump include a transformer to reduce voltage from 120 (I haven't been able ...
0
votes
1answer
79 views

HEF40106BP oscillator output frequency [closed]

I have a NuTone four note Door Chime, Mod# LA500K. I want to slow the chime cadence. There are two ICs: CD4017BE & HEF 40106BP. Can someone tell me if this is possible and how? (RC circuit?) ...
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vote
3answers
658 views

Deriving the formula of oscillation frequency for the Phase Shift Oscillator

My aim is to find the oscillation frequency of a Phase Shift Oscillator. I start by finding transfer function of the cascaded RC network. $$ V_o(s) = \dfrac{\dfrac{1}{C_3s}}{R_3+\dfrac{1}{C_3s}} ...
0
votes
2answers
501 views

Working of Wien Bridge Oscillator

I am studying Wien Bridge Oscillator. The part I do not understand is how the other frequencies die out. For example, let us say initial disturbance was not of the resonant frequency but a higher ...
0
votes
5answers
136 views

What is the name of this oscillator topology?

What is the name of the topology of the oscillator shown below? I try to understand how it works and what are the design equations. But in order to find that, I first have to know the name of the ...
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vote
0answers
178 views

Wien bridge oscillator LTSPICE

im looking for a good oscillator to implement in a circuit and I was trying to simulate a Wien Bridge oscillator in LTSPICE but I have no success as my output is always 0 V. Is there a special ...
0
votes
0answers
62 views

Do I need to use a programmable oscillator?

I can produce pwm signals with my mcu and I am intended to use this signal to feed another MCU's external clock input. But my output pwm signal voltage is 5V and I need peak to peak 2.5V signal and it ...
0
votes
0answers
112 views

How to use a crystal oscillator

I am trying to use a crystal oscillator as a clock signal for the PWMCLK input of a LED driver chip (TC62D723FNG) I have a FOX 1813-0245 8926 25.00000 MHz crystal oscillator I picked up at a local ...
2
votes
2answers
133 views

What is the tiniest, low-power, and efficient am transmitter?

Here are my constraints: I need to build an am transmitter, but it has to fit in a 1 inch diameter and ~1 inch height box. Since the box is very small, I plan to use a CR2032 battery, which is also ...
1
vote
1answer
72 views

Loop Controlled v. Full Swing Pierce Oscillator

I am going to be working with the Freescale MC9S12XE processor and trying to figure out the oscillator configuration. They offer the following options: Loop Controlled Pierce Oscillator Full ...
1
vote
1answer
94 views

Trouble with phase locked loop: phase comparator is just showing the VCO output (with picture)

I am using the CD4046BC for the first time, and do not understand something that is happening. I am using the type I phase comparator, which is just a simple XOR logic gate. When I have the input as a ...
-1
votes
1answer
80 views

Will a 5V crystal oscillator oscillate with a 3.3V supply?

My question is in the title. I was looking for a component, but I can only find it with 5V. There is no data sheet provided so my question is in general: Will a 5V crystal oscillator oscillate with a ...
0
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0answers
60 views

Crystal oscillator output impedance

I want to build a varactor frequency tripler (from 80 to 240 MHz). Can't find XO output impedance for an input matching network. I would appreciate any advice on this matter.
1
vote
1answer
77 views

Review and question about AD9838 circuit

I have tried to come up with a schematic of using AD9838. I used the eval. board schematic and modified it to my needs. The eval. board schematic can be found on page 9 here: AD9838 eval. board ...
5
votes
2answers
840 views

How to test a crystal resonator in board?

I have 2 quartz crystal resonators in my pcb board: 32.768 kHz & 20 MHz. They are connected to a Freescale MC12311 transceiver IC, which has an HCS08 micro-controller embedded in it. I want to ...
0
votes
1answer
129 views

zvs induction heater mosfet failure?

Hey guys my name is Barrett I'm an electrical engineering student and I'm new to the forums. I've been super excited to put a zvs induction heater together and I finally got all my parts turned it on ...
1
vote
5answers
97 views

Control resistances with voltage

Let's say I have an audio oscillator, which a resistor varies the tone. I have 5 different voltage sources, each representing a tone. How can I control the tone (vary the resistance) depending on ...
1
vote
3answers
153 views

What does FCY / F_CY stand for?

I've come across many equations in microchip datasheets that are based on this value and am looking for a central place to lookup definitions. F_OSC = oscillator frequency T_CY = 1 / F_CY = time to ...
4
votes
1answer
140 views

Why does my crystal oscillator spike so much?

I just got a new oscilloscope (Rigol DS1102E) and I'm new to EE in general. One of the first things I put on the scope was my 3.579Mhz "TKD" crystal oscillator. ...
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votes
1answer
136 views

how do oscillations build up initially although the circuit has no external applied input? [closed]

In practical we got some king of oscillation even before given input power. We have built wien bridge oscillator like this one. . image from electronicdesign.com
1
vote
0answers
166 views

simple schematic for 10.7MHz crystal-based marker generator

For FM tuner alignment purposes I want to build an outboard 10.7MHz marker generator to use in association with a piece of gear (ST1000A) that doesn't have one built in. They used to be available in ...
0
votes
1answer
126 views

What is the oscillator used for on HT12E/D? [closed]

Every tutorial I've found on the internet connects the oscillator in and the oscillator out with a resistor. What can these ports be used for?
0
votes
0answers
45 views

Can any one tell me the purpose of those two capacitors at the both end of XTAL1 and XTAL2 connected to crystal oscillator? [duplicate]

How does those two c2 and c1 capacitor affect clock input spectrum? What would happen if those two capacitors were not there? Are they mandatory to have?
0
votes
0answers
58 views

Difference between 3.3V half-size DIP oscillator and Full size DIP oscillator

I have often heard oscillators with 3.3V half-size DIP oscillator with 4 pins and Full-size DIP oscillator with 8 pins. Why would someone want to use half-size DIP or full size DIP?
4
votes
1answer
149 views

How is the negative resistance feature of tunnel diodes used in oscillators?

Can someone explain how the negative resistance feature of a tunnel diode is used in oscillators with the help of this circuit diagram: