Gamma Match in VHF/UHF Antennas

 Gamma match is an arrangement used to match the impedance in both HF, VHF and UHF antennas, typically for Yagi-Uda type of antennas. As HF Yagi antennas are quite large, I do not have an option to use them on my small terrace. I have homebrewed both VHF and UHF Yagi antennas with Gamma match for impedance matching. Though the impedance of a simple dipole of around 70 Ohms is suitable for usual commercial radios with 50 Ohms impedance, Yagi-Uda antennas with multiple parasitic elements may have much lower impedance in the range of 25 Ohms or lower. This needs matching and Gamma match is a popular method. It derives its name form the similarity to the Greek letter Greek letter gamma, that is the capital letter gamma (Γ).



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