Category: Electronics
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LiteVNA Review
The LiteVNA is a portable vector network analyser, it offers reasonable performance for a very low price, making it an ideal tool for electronics hobbyists and amateur radio operators, it can be had for under £100 from China. For those who are not familiar with a VNA, it measures the amplitude and phase response of…
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Crystal Radio Improvements
Previously I made a basic crystal radio, since then I’ve made a number of design improvements. Multiple Bands There is only a few medium wave stations where I live so I decided to add shortwave as well, to achieve this I used a rotary switch and a 7uH inductor, this is wound on a T50-2…
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Making a Crystal Radio
A crystal radio is a radio designed for receiving audio (voice) broadcasts, it was invented around the beginning of the 20th century and became extremely popular in the 1920’s and 1930’s, allowing millions of people to access radio broadcasts that otherwise would have been prohibitively expensive, the majority would have been self constructed sets rather…
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TinySA Spectrum Analyser Review
The TinySA is a low cost portable spectrum analyser that also functions as a signal generator, this is a true spectrum analyser that has a wide dynamic range and can measure a signal up to 960 MHz, it is developed by Erik Kaashoek and has open source firmware but not hardware. It features a 2.8″…
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Measuring Amplifier AC Impedance
Knowing the impedance of an amplifier or any electronic circuit can be very useful, for lower frequency applications it’s desirable to have the source impedance be much lower than the load impedance to minimize voltage drop, in RF applications and where maximum power transfer is needed it’s better to match impedance to avoid reflections, the…