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 […]
Calculations
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 […]
LC Oscillator Circuits: Explained with Calculations
An LC oscillator is a circuit which we can use to transform a direct current (DC) supply voltage into an alternating current (AC) output waveform. This output can exhibit various types of waveform shapes and frequencies which might range from complex forms to simple pure sine waves depending on the specific application requirements. These oscillators […]
Decibel Calculations: From Basics to Advanced Applications
We usually think of decibels as being used to measure loudness. But when designing amplifier and filter circuit layouts, we typically come across numerical values that have extremely wide ranges. For example, a total gain of 665 (19 multiplied by 35) is obtained through cascading two amplifier stages with power gains of 19 and 35 […]
Understanding Active Low Pass Filter Circuit with Calculations
As we learned in our previous tutorial, passive filter circuits depend exclusively on passive components such as resistors (R) and capacitors (C) to provide filtering characteristics. A simple example is a first-order low pass filter built with a series resistor and a shunt capacitor across a sinusoidal input. Active filters on the other hand use […]
Learning Passive Low Pass Filter Circuit Calculations
Basically passive RC filters are circuits that separate various frequencies within a signal. We can consider a signal as a collection of distinct-pitched noises. We can make an RC filter to only allow high-pitched sounds to pass through (such as a treble filter) or only the low-pitched sounds to pass through (similar to a bass […]





