Have you ever wondered why almost all RF and microwave systems have 50-Ohm characteristic impedance? Find out in 2 minutes. Quaxys offers skills-based quantum and microwave engineering courses Visit us at qauxys.com
This begs the question, why is there also 75 Ohm coaxial cable for video, TV etc?
@quaxys_academy
4 күн бұрын
Thanks for your question. There are a few reasons for using 75 Ohms. 1. As demonstrated in the video, a 73-ohm characteristic impedance results in minimal attenuation. Therefore, when dealing with weak signals from an antenna or an analog video link, 75-ohm cables are preferred. 2. A half-wave dipole antenna used in TV receivers has an impedance of 73 ohms at its resonant frequency, making it well-matched to a 75-ohm cable. 3. Moreover, a folded dipole antenna used for TV receivers has an impedance of 300 ohms. So, by using a 4:1 balun, a 75-ohm cable provides an excellent match.
@zedcarr6128
4 күн бұрын
@@quaxys_academy Thank you so much. 😲 Nearly 40 years I've been an engineer in electronics, electrics and mechanics, and this simple fact has never been explained to me, or have I ever bothered to ask the question. This is one of those nuggets of knowledge that is mind blowing. 😊 Subscribed!
@alansalari6319
4 күн бұрын
@@zedcarr6128Thank you for asking this important question.
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