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EFHW 49:1 Transformer Construction and Deployment


If you can't see the video, please insert this title URL into your browser search box:

https://www.youtube.com/watch?v=1BBg6vRybCo&ab_channel=KA5WPM

This is post 2450 in a continuing series of simple ham radio antennas.

End-Fed Halfwavelength Antennas (EFHW) are effective, simple antennas for both home and portable use.  Unlike dipole antennas which can be easily matched to 50 or 72 ohm coaxial cable, EFHWs exhibit a high impedance, necessitating a transformer to protect your transceiver.

In this well-made video from KA5WPM, we learn how to make a 49:1 transformer suitable for use with EFHW or random length long wire antennas.

Here are some general comments from KA5WPM:

This video shows how I made my 49:1 transformer for my End Fed Half Wave antenna. (EFHW)... (Click "SHOW MORE" below to see the Amazon links)...You will learn what you need to order and where you need to order it from and how much it will cost... and finally the results I am getting with this piece of wire... stay tuned.... 73 de KA5WPM This is an amazon affiliate link to the enameled wire I used. https://amzn.to/2GUCkGC This is the toroids on amazon.. Arrow.com is cheaper. https://amzn.to/2sgIX0Y I did find these 30KV 100 pf capacitors at a bargain! https://amzn.to/2Wm3tex PLEASE SUBSCRIBE AND CLICK THE BELL! If this kind of stuff interests you, please subscribe... Thanks

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Thanks for joining us today.

Aloha es 73, Russ (KH6JRM).

 

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