Anyone built this non-folded dipole array project? It uses 3/4" copper pipe, PVC stand offs and 75 ohm coax for the phasing harness...
http://forums.radioreference.com/attachments/antennas-coax-forum/16043d1213582941-4-bay-vhf-dipole-array-project-low-cost-high-performance-vhf-dipole-array.pdf http://forums.radioreference.com/antennas-coax-forum/109144-4-bay-vhf-dipole-array-project.html http://forums.radioreference.com/antennas-coax-forum/155082-hme-brewed-4-bay-uhf-dipole-array.html On Thu, Aug 27, 2009 at 3:19 PM, Burt Lang <[email protected]> wrote: > > > Actually 300 ohms is special. It is the impedance of a folded dipole > with equal diameter elements, the end result of bending a single piece > of tubing into a U. And the impedance is not affected by the spacing > between the elements (according to the handbook theory). > > Burt VE2BMQ > > John Sehring wrote: > > > > > > Yes, it does depend on the antenna, to wit, diameter of the elements & > > spacing between the elements. Can be made lower or higher than 300 > > ohms. There's nothing "sacred" about 300 ohm Z. It was a match for 300 > > ohm TV twinlead in the older daze. > > > > --John > > > > --- On *Thu, 8/27/09, Chuck Kelsey > > /<[email protected]<wb2edv%40roadrunner.com>>/* > wrote: > > > > > > From: Chuck Kelsey <[email protected] <wb2edv%40roadrunner.com>> > > Subject: Re: [Repeater-Builder] 2 meter folded dipoles for multi bay > > design information needed > > To: [email protected]<Repeater-Builder%40yahoogroups.com> > > Date: Thursday, August 27, 2009, 6:51 AM > > > > > > > > Depends on the antenna. > > > > A folded dipole, out in the open, with no matching, is a > > bit less than 300-ohms. > > > > > > Chuck > > WB2EDV > > > > > > > > start: 0000-00-00 end: 0000-00-00 > > > > > > >
