Alex Discovers Amateur Radio

13 How did Matty make the signal so clear at the end? It was terrible at the start. Sounds complicated all this audio stage and IF ! Yes but you don’t have to understand what’s going on inside to use it. Good, but I would like to learn more about how it works once I know how to use the controls. Different radios have slightly different controls, some easier to use than others, but they all do much the same thing … IF-DSP is before the audio stage so that makes it more effective. … they shape the incoming radio signal to get rid of any interference and focus on the signal you want to listen to # . There are a number of reasons why the call could have suddenly come in so strong: the other station might have increased their power; a change in the atmosphere could have improved propagation; Matty could have adjusted the receiver controls – in particular the DSP … … Simple DSP is like the sound card on a computer – it digitally processes an audio signal. The what? DSP - DIGITAL SIGNAL PROCESSING Roger Whisky 1 Alpha Whisky you are 5 and 9 - 1036 in Wallasey – good luck in the contest. QRZ from, from Mike 3 Uniform Alpha Yankee . # Today all this filtering and processing can be carried out by a home computer running the correct program. This is called S oftware D efined R adio - SDR. A radio receiver has several main stages. The Tuning and Radio Frequency (RF) stage which tunes in the wanted signal from the antenna and amplifies it. The Intermediate Frequency (IF) stage that provides more amplification and filtering out of unwanted signals. The detector which recovers (demodulates) the original audio signal. The Audio Amplifier which amplifies the audio signal. DSP Filter Analogue Signal