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4 Band Resistor
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Micropower VCO (Voltage-Controlled Oscillator)
This is a schematic diagram of a micropower voltage-controlled oscillator circuit. This circuit can generate square and triangle wave outputs and only need..
Precision Oscillator With 20ns Switching
Precision oscillator can be built using quartz crystal, but with proper component selection, you can also build one with RC (resistor and capacitor) circuit..
Low Distortion Wien Bridge Oscillator
This Wien bridge oscillator uses incandescent lamp to stabilize its amplitude. This amplitude stabilization gives a low distortion output. Multiple frequency..
100MHz Varicap Oscillator
This is a 100MHz Varicap Oscillator circuit. This circuit can provide modulation signals less than 28V and frequency deviation of 28 MHz peak-to-peak. This..
Cmos Pair 2-Mhz Crystal Oscillator
This is a 2 MHz crystal circuit using CMOS pair. This circuit is ideal for uses in digital watches and clock because this circuit has low power drain. The..
Wien-Bridge Sine-Wave Oscillator
This is a Wien-bridge sine-wave oscillator circuit. This circuit uses negative-feedback stabilization to make sure the gain won`t go higher than unity to..
Voltage Controlled Oscillator for Commercial FM Band
VCO (voltage controlled oscillator) is an electronic signal generator which produce a signal that has variable frequency depends on a voltage level at its..
Crystal Oscillator with CMOS Inverter
This is an astable multivibrator (oscillator) circuit using CMOS inverter. This circuit uses CD4007 or MC14007. This circuit has operating frequency range of..
Electronic Gain Control in Quartz-Stabilized Oscillator
This is a quartz-stabilized oscillator circuit with electronic gain control. Replacing the common filament lamp for amplitude stabilization, this circuit use..
Square Wave Oscillator using Comparator/Op-Amp
The circuit shown in this schematic diagram is a square-wave oscillator circuit. The main component of this oscillator circuit is LP165/365 comparator. As..
Frequency Modulated Oscillator (for FM Transmitter)
An oscillator can be built using LC (inductor-capacitor) tank circuit. When we vary the capacity of the capacitor in LC tank circuit then the frequency of the..
The local oscillator for 10.7 to 2.5MHz conversion
A 52 MHz third overtone crystal is typically 30 ohms at its series resonance according to manufacturer specifications. The crystals used for the prototypes have nearly ten times lower series resistance but they were very expensive. An oscillator can be seen as an amplifier which has feedback through a filter. The amplifier of a series resonance os
A low noise four phase crystal oscillator
A 10 MHz crystal is typically 4 ohms at its series resonance and 40 kiloohms at its parallell resonance. To get low sideband noise the power dissipated in the crystal has to be reasonably large, the design used here dissipates 0. 2mW in the crystal, 7mA and 30mV across the crystal. An oscillator can be seen as an amplifier which has feedback throug
The FV-1 Crystal Oscillator
The Fv-1 has internal circuitry to support an external crystal, preferably a 32768Hz watch crystal. These crystals are extremely inexpensive and widely available. Frequencies other than 32768Hz are available, but not as cheap and not as plentiful. If the system the FV-1 is integrated into has local clocks available, a logic level clock signal can
Square Wave Oscillator
It`s most useful application is as a Signal Injector for radios and TV`s. A square wave is the most suitable for testing the IF (Intermediate Frequency) strip as the signal will pass through the IF transformers without any attenuation, no matter what the tuned frequency of the circuit. Normally only a sine wave of the correct frequency will get...
A phase-shift audio oscillator with excellent distortion characteristics thanks to "softened" diode limiting provided by the 1N914 and resistor divider and degenerated gain provided by the 68 ohm emitter resistor. For minimum distortion, increase the 68 ohm resistor to a point just below where oscillation stops. A simple buffer may be adde
VHF Overtone Oscillator
VHF overtone crystals can be difficult to use due to the many frequencies at which the crystal is perfectly happy to oscillate. A typical 100 MHz, 5th-overtone crystal will oscillate at approximately 20 MHz, 60 MHz, 100 MHz, and even 140 MHz, not to mention other, unintended modes that such crystals often have. Most VHF overtone oscillators use...
Linear electronic oscillator circuits, which generate a sinusoidal output signal, are composed of an amplifier and a frequency selective element,a filter. An oscillator circuit which uses an RC network, a combination of resistors and capacitors, for its frequency selective part is called an RC oscillator. Two configurations are common. One is...
A voltage-controlled oscillator or VCO is an electronic oscillator designed to be controlled in oscillation frequency by a voltage input. The frequency of oscillation is varied by the applied DC voltage, while modulating signals may also be fed into the VCO to cause frequency modulation (FM) or phase modulation (PM); a VCO with digital pulse
Echo Tone Oscillator
This simple circuit amplitude-modulates a single tone in such a manner to approximate the echo effect one might obtain, for instance, with sonar apparatus. Any reader who has been on a sonar-equipped vessel will realize that some imagination is required to appreciate the similarities among this simple scheme and the "real thing. " However, this cir
Twin-T Audio Sine Wave Oscillator
The circuit illustrated produces a clean sine wave signal ideal for audio testing, or wherever a good-quality sine voltage source is required. It uses one integrated circuit which is a widely-available dual operational amplifier, the Texas Instruments TL072CP. The values shown provide an output frequency of about 1000 Hertz. This frequency may be
Single-Supply Wien Bridge Oscillator
Tuned-base Armstrong oscillator
The circuit in view (D) has all three requirements for an oscillator: (1) amplification, (2) a frequency-determining device, and (3) regenerative feedback. The oscillator in this schematic drawing is a tuned-base oscillator, because the fdd is in the base circuit. If the fdd were in the collector circuit, it would be a tuned-collector oscillator.
Crystal oscillators are those in which a specially-cut crystal controls the frequency. CRYSTAL-CONTROLLED OSCILLATORS are the standard means used for maintaining the frequency of radio transmitting stations within their assigned frequency limits. A crystal-controlled oscillator is usually used to produce an output which is highly stable and at a v
Frequency counter Oscillator schematic
The oscillator provides a 1MHz and a 1khz clock. The 1MHz clock is used as the clock for the microcontroller and as timebase for millisecond measurement. I use a 2MHz and divide it by 2 in order to guarantee a 50% duty cycle. Then three halve HC390 are used as divider by 1000 which can be externally reset. This is necessary to make sure the millis
Precision Clock Generator
The device presented here can generate a complementary clock signal at frequencies of 10Hz to 10MHz in steps of factor10. Thus, I chose to call it "10xHz clock generator" (with x being a number between 1 and 7). It can also be used to manually create clock impulses using a press button. The frequency is selected using two press buttons/swiches: S1
The circuit is a fairly easy design: It consists of the actual VCO (ICL8038 with supplement parts), the sine and triangle output stage (LT1210) and the CMOS-compatible output stage using the MOSFET driver chip ICL7667. The ICL8038 and all parts around on the lower half of the sheet make up the actual oscillator which is a modified design based on
Small Footprint Square Wave Oscillator
This is a small footprint 50% duty cycle square wave oscillator with variable frequency from 10kHz to 30MHz. The frequency range can be extended to 1kHz by using 1M instead of 100k for R6. The sheet presented here drives the square wave directly into 50Ohm; the output stage uses 5 parallel 74AC04 CMOS in
Poor Mans DDS Board
The applied microcontroller is an ATMega8 clocked at 16MHz. This microcontoller can shift out arbitrary wavefroms from its flash or SRAM storage at a rate of 2MS/s (and even faster!). The 8bit data is fed from portD to the AD converter ( Analog `s AD7524) connected as voltage DAC. The USB data lines are shared with the DA data forming a common 8bi
The Colpitts circuit, like other LC oscillators, consists of a gain device (such as a bipolar junction transistor, field effect transistor, operational amplifier, or vacuum tube ) with its output connected to its input in a feedback loop containing a parallel LC circuit ( tuned circuit ) which functions as a bandpass filter to set the frequency o
A Hartley Oscillator
In the Hartley circuit (Fig. 14 B), the amplified energy of the plate circuit is fed back to the grid circuit by means of fluctuating magnetic fields. They are both of the so-called magnetic feedback type. The Hartley circuit uses only one coil, part of which is in the plate circuit and part in the grid ci
Astable Oscillator Circuits
Colpitts Oscillator Circuits
Crystal Oscillator Circuits
Hartley Oscillator Circuits
RF Oscillator Circuits
Sine Wave Oscillator Circuits
Square Wave Oscillator Circuits
Volt Controlled Oscillator Circuits
Wein Bridge Oscillator Circuits
Pierce Oscillator Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
Digital Signal Integrity
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