Circuit resonance forms the basis of tuning. A series or parallel tuned circuit will resonate when the reactance’s of C and L are equal. The reactance of a capacitor falls exponentially with increasing frequency whilst for an inductor it increases in a straight line. At resonance the series circuit will present a low impedance to the applied signal, and the parallel circuit having a high impedance. TEST YOUR UNDERSTANDING: Your objective in this lesson is to become familiar with radio tuned circuits and how they work. Essentially they are filters that either allow (Accept) Or block (Reject) either a single frequency or group of frequencies. Using the internet, search series & parallel tuned circuit, find some suitable circuits and note down the capacitor, resistor and inductor values along with the operating frequencies. These will also be found in any standard electronics textbooks or component catalogues. Draw a small table of the values and input to each of the topics. It would be sufficient if at this stage you gained an idea of what combinations of values are required to build Radio Frequency Tuned Circuits. Learning electronics is all about gaining experience and sufficient confident knowledge to apply to a project or fault, and that only comes with spending time understanding the theoretical stuff. We believe our approach, whereby you can learn this interactively is the most interesting way to achieve that. Luckily electronics physics can always be exactly replicated exactly and return the same result for the same input conditions.
