This Wien-bridge sine-wave oscillator uses a 2N3819 as an amplitude stabilizer...
In this circuit, an LM741 op amp drives a Wien-bridge network using two zener diodes as..
This phase-shift oscillator is useful for audio oscillator applications. Adjust R7 for a good sine w..
A Wien-bridge oscillator can be made Vllriable by using two frequency-determining parts that are varied simultaneously at high tracking accuracy. High-quality tracking potentiometers or variable capacitors are, however, expensive and difficult to obtain. To avoid having to use such a component, this oscillator was designed to operate with a single potentiometer. ..
This oscillator uses a bridge circuit with an optoisolator as a gain-control device. The resultant distortio..
The sine wave output has a relatively high output impedance (1K typ). The circuit provides buffering, gain, and amplitude adjustment..
U1A, an op amp, oscillates at the frequency at which the phase shift in the Wien bridge network is exactly zero degrees. Changing bridge component values changes the oscillator frequency. In this circuit, we need change only the two resistors to do this. S1A chooses a value among Rl through R6, and SIB similarly selects a value from R7 through R12. U1A must provide enough gain to overcome losses in the bridge, but.not so much gain that oscillation builds up to the point of.....
This circuit produces a pure, - 80-dB THD sine wave with a frequency that is equal to the fc of IC3"s filter. A TT..
A TTL counter, an 8-channel analog multiplexer, and a fourth-order low-pass filter can generate 10- to 25-kHz sine waves with a THD better than -80 dB. The circuit cascades the two second-order, continuous-time Sallen-Key filters within ICS to implement the fourth-order low-pass filter. To operate the circuit, choose the filter`s cutoff frequency,^, by tying IC3`s D0 through D6 inputs to-5 V or ground. The cutoff frequency can be at 128 possible levels between 1 and 25.....
This compact LC oscillator offers a frequency range of about 1 kHz to almost 9 MHz and a low-distortion sine-wave ou..
The oscillator delivers a high-purity sinusoid with a stable frequency..
The quality of the sine wave depends on how closely you match the components in the twin-T network..
Lamp LI stabilizes the loop gain at higher frequencies while the limiting action of R2, CRI, and CR2 prevents clipping at low frequencies and increases the frequency adjustment range from about 3:1 to greater than 10:1.
A 555 timer operating in the astable mode generates the driving pulses and two 4518 dual BCD (binary coded decimal) counters provide the square waves. A TL081 op amp serves as an output buffer-amplifier, and potentiometers Rl and R2 are used in order to control the pulse`s frequency and amplitude, respectively. The output-frequency range can be varied by changing Cx. For example, a value of 0.1 gives a range from about 0.1 to 30 Hz, and a value of 470 pF gives a range.....
In this circuit, a square wave is filtered by a high-order low-pass filter so that a -3-dB frequency will eliminate most harmonics of the waveform. As a result, the filter outputs a fundamental sine wave. This method is applied to generate a sine wave by using a switched- capacitor filter (MAX292) (see the figure). This circuit offers wide frequency range (0.1 Hz to 25 kHz),..
Using a Quad NAND Gate, the TTL oscillator can use fundamental crystals between 1 and 10 MHz. The sine..
Basically a Hartley oscillator using a triple-emitter follower, this oscillator can be used at audio and low ra..
Cascading two identical integrators will thus result in an overall phase shift of 180Â° and an amplification of unity (p..
A highly-stable 60-Hz sine wave can be delivered with this circuit, which offers a different and much simpler approach to gaining a stable amplitude...
This oscillator uses two transistors and operates the crystal in the fundamental mode. CT and C2 should..
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