When we talk about charging a capacitor it is not something that can happen instantly. This is because capacitors have specific current-voltage i-v characteristics that shift depending on time. If you connect a resistor R and a capacitor C together into a circuit, you will get what is called an RC charging circuit. This setup […]
Calculations
Twin-T Oscillator Circuit: From Calculations to Practical Applications
I have personally used the Twin-T RC oscillators a lot and I find it very interesting, mainly because it is designed to generate a sinewave output. It is ideal for fixed-frequency applications much like the Wien-bridge oscillator. The name “Twin-T” oscillator comes from the fact that it employs two “Tee”-shaped RC networks in the feedback […]
Understanding Quartz Crystal Oscillator Circuits, with Calculations
Quartz crystal oscillators allow us to overcome a number of issues that may have a substantial impact on the frequency stability of an oscillator circuit. These influences include, but are not restricted to, temperature variations, fluctuations in the load connected to the oscillator, and even changes in the DC power supply voltage. All of these […]
Wien Bridge Oscillator Circuit Explained with Calculations
In the RC Oscillator tutorial, we saw that by connecting resistors and capacitors together with an inverting amplifier we can create an oscillating circuit. One of the simplest ways to generate a sine wave is through a circuit known as the Wien Bridge Oscillator. This oscillator replaces the traditional LC (inductor-capacitor) tuned tank circuit with […]
Colpitts Oscillator Working, Explained with Calculations
Compared to the Hartley oscillator that we looked at in the last lesson, the Colpitts oscillator represents a very different way of designing tuned tank circuits. Similar to the Hartley oscillator which creates a sinusoidal output waveform by implementing an LC resonance sub-circuit between the collector and base of a single-stage transistor (BJT) amplifier, the […]
Understanding Hartley Oscillator Circuit, with Calculations
The basic LC Oscillator tank circuit that we discussed in one of our earlier posts has a significant limitation: it cannot alter the magnitude of its output oscillations. This means that the oscillations might be either too large or too little, making it difficult to get the desired results. It might also be difficult for […]