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Showing posts with the label Construction of a 9-1 unun.

Construction of a 9-1 unun. Post #1122.

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If you can't view this video, please insert this title URL into your browser search box: https://www.youtube.com/watch?v=L4jGNFGN-RQ. Here's a handy item that will make using an end-fed random length wire antenna easier and more efficient.  A 9-1 unun used in combination with an antenna "tuner" and a good ground radial or counterpoise system will make that random wire perform better than expected. This short video tutorial from "mk1tina" guides you through the process of designing, building, and using a 9-1 unun for your end-fed antennas.  According to "mk1tina", the core used is a T200-2 with 9 trifilar turns of enamel wire. The case is fairly small, measuring 120mm by 80mm.  Although the unit is rated at 400 watts, it may be best to run power levels below 100 watts to keep components cool.  You may want to bring one of these 9-1 ununs with you to the ARRL Field Day, just in case you may be using a random length wire antenna. For the late...

Simple Ham Radio Antennas--Construction of a 9-1 unun. Post #901.

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If you're having trouble viewing this video, please insert this title link into your browser search box: https://www.youtube.com/watch?v=L4jGNFGN-RQ.  Here's a handy 9:1 unun from m1tina that will make your use of a longwire antenna much more efficient and pleasurable.  The 9:1 unun is an impedance transformer to feed high impedance, end-fed (unbalanced) random wire antennas, which may exhibit an impedance of a few hundred ohms.  The unun transforms the impedance of the wire into something closer to 50 ohms--something your transceiver will appreciate.  The 9:1 unun is wound on a T200-2 core and has 9 trifilar turns of enamel wire.  This is a great weekend project! For the latest Amateur Radio news and information, please visit my news site at http://www.kh6jrm.info. If you're a radio amateur living on the Big Island of Hawaii, be sure to check my ARRL PIO (public information officer) blog at http://bigislandarrlnews.wordpress.com. Be sure to check out th...