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> A potential positive advantage of the layered coiled air core >transmission line balun over the solenoid wound balun is the lowering of the >Q of the balun. This lowering of the Q of the balun can result in a >significant broadening of the balun's common mode impedance bandwidth. This >broadening of the common mode impedance bandwidth can substantially improve >the multiband capability of the coiled air core transmission line balun. A >high Q narrow bandwidth balun is converted into a lower Q wider bandwidth >balun when one shifts from the solenoid to the layered winding method. Not >bad, in the correct application. Careful examination of George Badger's >origional data on his layer coiled air core transmission line balun, >"Badger" balun, shows that he measured a very useful common mode impedance >bandwidth from below 20 meters to about 10 meters. This led him to state >that he had developed a "new" balun type. He is close to the truth: a >relatively broadband, high-ish common mode impedance bandwidth, low cost, >with high power capability and without the limitations of the vintage >"voltage" baluns popular at the time. Sounds great to me! On the other hand, a string of beads, assuming you use enough of the right ones, can give you the same broadband response, similar common mode impedance, lower wind profile, better mechanical mounting, and no place for birds to nest. I have bought beads in bulk from Amidon, and also bought N8UG's kits for ~$7.50 each, which are awfully convenient when you only need one or two. For price, weather resistance and power handling, I think the B-1s are hard to beat. BTW in case Ken Hirshberg hasn't written you back, he's the guy who builds the Force 12 baluns for them... 73, Pete N4ZR Contesting is! The World Contest Station Database is waiting for your input at http://www.qsl.net/n4zr -------------------------------------------- Force12Talk mailing list provided as a service by Force 12 Antennas, Inc. Force 12 Web site: http://www.qth.com/force12 Submissions: send to Force12Talk@qth.com To unsubscribe: send a blank e-mail to Force12Talk-leave@qth.com Force12Talk Message Archive: http://www.qth.com/force12/list/force12talk For problems with the list, contact n4zr@qth.com |