Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
The Colpitts Oscillator
A typical Colpitts oscillator design. This circuit is very similar in operation to the Hartley oscillator described in Oscillators Module 2. 1 but the Colpitts LC tank circuit consists of a single inductor and two capacitors. The capacitors form in effect, a single `tapped` capacitor instead of the tapped inductor used in the Hartl
Colpitts Oscillator Practical Project
Build the Colpitts oscillator shown using either breadboard (proto board) or strip board, then test the oscillator`s operation using a multi meter and oscilloscope. This Colpitts oscillator produces a sine wave output in excess of 12Vpp at an approximate frequency set by the values chosen for L1, C2 and C3. It will operate from a 9V battery, or a
Crystal Sine Wave Oscillators
Where good frequency stability is required, in applications such radio transmitters, basic LC oscillators cannot guarantee to hold their frequency without some drifting, which can be caused by quite small changes in supply voltage (although stabilised power supplies help avoid this) and changes in temperature. The effects of resistance and stray
Wien Bridge Oscillators
A basic Wien Bridge Oscillator using a filament lamp with an op amp. It is a property of filament lamps that the resistance of the tungsten filament increases in a non-linear manner as the filament heats up. The lamp in Fig. 3. 4. 1 is connected in the negative feedback potential divider that sets the gain of the non-inverting ampli
BJT Astable Multivibrators
The basic bipolar transistor (BJT) version of an astable multivibrator as shown in Fig. 4. 1. 1 has two outputs that repeatedly change state at a rate determined by the time constants of its feedback network. Although largely superseded by its equivalent op amp or timer IC versions in many applications, it is still a useful and flexible design...
Designing 555 Astables
If an oscillator of a particular frequency and mark to space ratio is required, (see Fig. 4. 4. 1) the method would be to calculate periodic time from the required frequency and the discharge time and charge time using the formulae for tD and tC described in Oscillators Module 4. 3. To do this, some component details will be needed. Starting...
The 555 Monostable
The 555 timer is so named because its primary mode of operation is intended to be in monostable mode. Operating as a monostable, it does not fit the strict definition of an oscillator because, unlike true oscillators, it requires an input signal to trigger its operation, however the fact that the 555 timer can be used in both monostable and astabl
LED Torch Uses Blocking Oscillator
This simple LED torch is driven by a 2-transistor blocking oscillator which steps up the voltage from a 1. 5V cell. It relies on the inherent current limiting of the 150 µH choke to protect the white LED from over-drive. With a 9V zener diode in place of the white LED, it could also provide a 9V supply provided the current drain is modest.
Safe Oscillator For Watch Crystals
This circuit was developed to allow watch crystals to be used in an existing CMOS oscillator circuit that was to run from a 12V supply. The problem is that these crystals only work up to a supply voltage of about 6V. Any more than that and the crystal will be over-driven, causing it to shatter. This circuit solves the problem by using LEDs 1 & 2 a
Switchable Output Crystal Oscillator
This oscillator circuit permits crystals to be electronically switched by logic commands. The circuit is best understood by initially ignoring all crystals. Furthermore, assume that all diodes are shorts and their associated 1kO resistors open. The two 1kO resistors at the non-inverting input of IC1 (LT1016) set the output to half the supply, ie,
The phase shift oscillator of Figure above produces a sinewave output in the audio frequency range. Resistive feedback from the collector would be negative feedback due to 180o phasing (base to collector phase inversion). However, the three 60o RC phase shifters ( R1C1, R2C2, and R3C3) provide an additional 180o for a total of 360o. This in-phase
555 audio oscillator
A oscilloscope would be useful in analyzing the waveforms produced by this circuit, but it is not essential. An audio detector is a very useful piece of test equipment for this experiment, especially if you don`t have an oscilloscope. The "555" integrated circuit is a general-purpose timer useful for a variety of functions. In this experiment, we
For successful circuit-building exercises, follow these steps: Carefully measure and record all component values prior to circuit construction, choosing resistor values high enough to make damage to any active components unlikely. If there are any substantial errors (greater than a few percent), carefully check your circuit`s construction...
Inductive Electronic Oscillator Circuit
The oscillator circuits presented on this page are from expired or non-maintained U. S. Patents. All circuits are presented in "Electronic Workbench 5. 12" or "Multisim 7 circuit simulation formats". A note on spice simulation of electronic oscillator circuits. All of the oscillator circuits presented on this web page have been simulated using...
Wien Bridge Oscillator
In this experiment, an oscillator is constructed using an operational amplifier and some other passive elements. This configuration for the oscillator is called Wien Bridge. The frequency of the oscillator is determined by R4, R5, C1, and C2 elements. In this circuit, they are chosen so that the frequency is 1 khz. The feedback coefficient ( ²)
sine wave oscillator
In case of Japan, the electricity to be using in the home is 50 Hz or 60 Hz. In case of 50 Hz, the 1-cycle sine wave occurs the 50 times for the 1 second. 60 Hz are the 60 times. There is a way of making make the Lissajous as the way of understanding that the sine wave relates to the circle. In case of the sine wave which doesn`t have the distorti
sine/cosine wave oscillator
When adding an alternating current signal to the capacitor, the wave position (the phase) of the charging current of the capacitor and the voltage of the capacitor shifts by 90 degrees. When adding an alternating current signal to the coil, it changes contrary to the capacitor. The change of the voltage moves ahead by 90 degrees with the change of
Using a VCXO (Voltage-Controlled Crystal Oscillator) as a Clock (CLK) Generator
The term VCXO stands for Voltage Control Crystal Oscillator. The frequency of such an oscillator can be adjusted by a small amount through changing the control voltage. VCXO CLK generators have been used in various applications, such as digital T..
Replacing Crystals and Ceramic Resonators with Silicon Oscillators
A short note describing how to replace crystal and ceramic resonator clock circuits with silicon oscillators and highlighting some of the technical advantages offered by these devices in microcontroller clock applications..
Analysis of a Digitally Controlled Wien-Bridge Oscillator
This application note analyzes the details of a Wien-bridge oscillator, shows how a JFET maintains oscillation, and demonstrates adding a digital potentiometer (digipot), rather than a variable resistor, to improve stability and flexibility..
Low-Power 32kHz Oscillator Operates Over Wide Supply Range
Design a 32kHz wide supply range oscillator with a low-power comparator, a reference and crystal oscillator..
Voltage Controlled Oscillator 1V/Octave Tracking
UJT RELAXATION OSCILLATOR
At the point Vp the Emitter triggers and TURN the ujt ON, until this point ; the emitter is isolated(doesnt conduct) from the transistor so no Current Conduction occurs between Base1 and Base2.
ASTABLE BLOCKING OSCILLATOR
Assume initially, that there is a voltage Vc on capacitor C1 larger than Vbb-Vg. Where Vg is the cut in base to Emitter voltage and g represent Gamma. Hence the transistor is off and the capacitor C1 discharges exponentially towards ground with a time constant R1 C1. When V1 becames equal to Vbb-Vg, the base current starts to flow and the transist
Oscillator circuit schematic
This web page describes the radio transmitter unit that flew aboard the Cirrus One rocket in April 2001. The intent of including the transmitter as payload was to: As the Cirrus One rocket was expected to achieve an altitude that would be well out of visual range at 10, 000 feet (3 km. ), it was felt that there could be recovery difficulties if the
Audio Oscillator circuit
The first was a simple single transistor RC audio oscillator built for a ham buddy. The breadboard circuit was literally a ball of components. Everything was just tack soldered together without a supporting circuit board. When my buddy asked for the breadboard, I figured he wanted the parts so he could rebuild the circuit in a more permanent...
Pierce type crystal oscillator circuit
The Tuna Tin 2 was originally designed by Doug DeMaw, W1FB in 1976. It appeared in QST, and was subsequently built by hundreds of QRPers, who were attracted to the project by the relatively easy parts availability. In fact, at the time of publication of the article, you could stop by the local Radio Shack and pick up everything needed except for t
Those variations, (in effect an alternating signal), will be passed via the coupling capacitor to the next stage - shown by the arrow to the right. We can replace one variable resistor with another. Consider R1 to now be replaced with any one of the devices shown in this following diagram. Each can act as a variable resistor: Other connections mus
Hewlett-Packard HP-200C audio oscillator
After repairing a couple of Hewlett Packard vacuum tube voltmeters, I read up on some of the company history. I was able to locate a HP-200C oscillator. This HP-200C is very close in design to the company`s initial product. It is a Wien bridge resistance-tuned oscillator with the famous light-bulb stabilized negative feedback circuit designed by W
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
Interconnection and Timing of Digital Circuits
CMOS Circuits Tutorial