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Hartley Oscillator Circuits
Hartley Oscillator Circuits
Hartley oscillator requires no coupled inductors
Examine a traditional Hartley oscillator circuit, and you`ll note its trademark: a tapped inductor that determines the frequency of oscillation and provides oscillation-sustaining feedback. Although you can easily calculate the total inductance required for a given frequency, finding the coupling coefficient, k, poses technical difficulties and...
The I.F. amplifier is similar to the one used in the 80M receiver project . The original design has been modified by putting a couple of LED`s in the source circuit of each Mosfet. The voltage drop across the LED`s keeps the source voltage at about two volts. This results in a much greater AGC range. This arrangement was suggested by N6BIU....
High Voltafe Generator
This is a series regulator with Q900 being the control ele- ment, Q901 a driver, and Q902 an error amp. ZD900 forms the emitter reference voltage source. Since the generated high voltage and other voltages are linked by means of the magnetic field of T900, any change in H.V. will be reflected back to all of the other voltages.
This circuit was used to stop all the BFO drift. The circuit is extremely stable. Turn the receiver off, and then on at any time and temperature, the BFO frequency is exactly the same. The resonator is a Murata CSB 455E. Murata's series number is CSBLA_E 430-509kHz. The data sheet is a .pdf file and the information on this resonator starts on...
variable Hartley oscillator
Hand and body motions in proximity to the sensing antennas produce frequency changes in a Hartley oscillator operating at approximately 750kHz. The signal from this variable oscillator is mixed with a constant reference frequency in a ring modulator and the result passed through a single pole of low pass filter to leave only the difference...
The Hartley oscillator is an LC electronic oscillator that derives its feedback from a tapped coil in parallel with a capacitor (the tank circuit). Although there is no requirement for there to be mutual coupling between the two coil segments, the circuit is usually implemented as such. A Hartley oscillator is essentially any configuration that us
Comparison between Hartley and Colpitts oscillator
Op Amp based Hartley oscillator
Build an oscillator that will satisfy a few requirements. The main requirement is to have exactly one capacitor. Another one is to have high Q and sine wave output. I am considering Hartley`s oscillator design. Since it has only one cap. I don`t what to built the biasing network and select a transistor that will suit the oscillator`s needs, so I...
Can a Hartley Oscillator be built using Fixed Inductors
An Hartley Oscillator circuit can be made from a pair of series connected coils. I had a couple of 22mH fixed inductors, which I hooked up on a breadboard with the other needed pieces. When I test the transistor amplifier independently, it seems to be working. However, there is no sign of oscillation in this circuit. So my ignorant question is,...
The Hartley Oscillator is characterised by an LC circuit in its collector. The base of the transistor is held steady and a small amount of signal is taken from a tapping on the inductor and fed to the emitter to keep the transistor in oscillation.
Hartley oscillator circuit
hartley oscillator circuit tutorials
hi Im trying to construct a Hartley Oscillator. I am using a bypassed common emiter and i am trying to get a 200kHz 2Vp-p oscilation. With a BC547B..
Hartley oscillator design with opamp
Hi! I made an opamp hartley oscillator using a certain electronics simulator and even though simulation takes place I`m unable to get any oscillation..
Voice Transmitter Via FM Band 2 VHF by Hartley Oscillator
The circuit was designed to operate a frequency modulation voice transmitter over the FM band 2 frequency range of VHF. Transmitter an electronic device..
Hartley Oscillator Calculator
Q is the transistor, L1, L2, C resonant circuit formed, L2 double as feedback network, through the coupling capacitor Cb will be sent to feedback voltage transistor base. Figure 2 shows the communication channel, resonant circuit with three endpoints and the three most connected transistor, it is known as the inductive three-point oscillator...
Hartley Oscillator Tutorial and Oscillator Design
Hartley Oscillator Tutorial and the theory behind the design of the Hartley Oscillator which uses a LC Oscillator tank circuit to generate sine waves..
Definition of a Hartley oscillator
A Hartley Oscillator is a style of oscillator that uses two series connected inductors or an inductor with a center tapped coil, along with a capacitor. The tank circuit is formed by the inductor and the parallel capacitor. An oscillator circuit requires an amplifier which has a feedback path between the output and input. The feedback point for th
The HARTLEY OSCILLATOR is an improvement over the Armstrong oscillator. Although its frequency stability is not the best possible of all the oscillators, the Hartley oscillator can generate a wide range of frequencies and is very easy to tune. The Hartley will operate class C with self-bias for ordinary operation. It will operate class A when the
The Hartley Oscillator
The Hartley Oscillator is a particularly useful circuit for producing good quality sine wave signals in the RF range, (30kHz to 30MHz) although at the higher limits of this range and above, The Colpitts oscillator is usually preferred. Although both these oscillators oscillator use an LC tuned (tank) circuit to control the oscillator frequency, Th
Single 10 Shunt Fed Hartley Oscillator for 80 meter CW
This Hartley oscillator was built on the remains of a single tube Hartley using a single 45. The original circuit I constructed was one that was published in a 1932 QST article by George Grammer. As it turned out, both of the 45s I had were weak, so the oscillator only would run when it was loaded very, very lightly. I did, however, have a good 10
Hartley oscillator circuit
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
Transistor Hartley Oscillator
Any vacuum-tube oscillator configuration has an equivalent transistor circuit. For example, consider the vacuum-tube oscillator, illustrated in Fig. 6-1 (A), which represents one form of Hartley oscillator. Positive feedback is accomplished by arranging the resonant tank E to be common to both the input grid and output plate circuits. The...
Astable Oscillator Circuits
Colpitts Oscillator Circuits
Crystal 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...
DIY HV Variable Capacitor
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Digital Signal Integrity