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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
Recording circuit of phone conversations using PC
This circuit is used to record telephone conversations on your landline telephone. All you will need is this small circuit and subscription of your PC. There are few times when we forget what we said or told us. So we need recording. Sometime, not many years ago, recording of this kind of conversation was done with a small tape recorder. The...
FM Micro-Transmitter Bug Surveillance Circuit
The transmitter we recommend to build is quite simple. It can even be built by a beginner. However, unlike the ease of construction and its small size, it is almost certain that it will impress you with its outstanding performance. Its autonomy is 12-15 hours, with a 9 volt battery and its range is from 100 to 300 meters depending on the...
Construction of 50Watt 8Ω two-way Hi-Fi Speakers
The presented speakers are distinguished for their small dimensions and their extraordinary sound. Our home space is often limited and prohibitive for large speakers. This limitation does not mean that we will stay without high Sound Quality. Its design is simple, low cost and is easy to construct. Speaker types are too many and are designed in...
GSM modem circuit with Wavecom WMOi3
Modems are devices that connect either remote devices to a computer, or two or more computers to each other. Their connection is usually wired. The GSM modem we present is wireless. It can connect two computers, a computer with the internet or even be the central unit for a data acquisition system. Generally the construction is a GSM phone...
1W UHF Linear Amplifier with BLW33
This circuit is an amplifier for small transmitters operating in the UHF band, specifically in the 450-800MHz range. The amplifier works in class A and we used the well-known Philips BLW33 transistor for its manufacture. The construction, although simple, can be said to be quite critical due to the high frequency singularity. To achieve this, a...
8W Amplifier with TDA2003 circuit
Many times a small amplifier is needed to meet the needs of small spaces. This amplifier can be either mono or stereo, with this circuitry you can comfortably drive two small speakers. To build the amplifier you do not need anything but a few materials and a small power supply. The power of the amplifier, although low power, will solve many...
FM Linear Amplifier 400mW
This amplifier is intended for amplifying low signals from oscillators in the FM band. It does not have frequency regulators with variable capacitors and coils, it has a wide range and moderate power capable of driving several linear amplifiers. The whole construction is based on the two low-power 2N4427 transistors, which are designed for the...
50 Watt Hi-Fi power amplifier circuit
SGS Thomson's integrated TDA7294 is a high-frequency acoustic power amplifier, with true high-precision specifications, suited for all relevant applications. Its main feature is much higher output power than is usual in amplifiers with similar distortion performance. According to its manufacturer, the output stage of this 15-pin integrated can...
RF Remote Control Switch Rx-Tx circuits
This circuit consists of a 2048 radio remote control transmitter and the corresponding wireless receiver with very high reception sensitivity and low consumption. The combination of the two above gives a high-reliability remote control, ideal for security systems, alarms, automation, etc. At home, in the car and elsewhere. Using the wireless...
Digital Signal Integrity
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