Read all but if lazy just go to cookbook near end: http://audiosystemsgroup.com/RFI-Ham.pdf
For some useful more detail analysis: http://fermi.la.asu.edu/w9cf/articles/balun.pdf Forget you ever heard of the term "balun" jim ab3cv On Mon, Nov 5, 2012 at 2:37 PM, Don Wilhelm <[email protected]> wrote: > Randy, > > That "balun" will not be very effective below 6 meters. The inductance > of each winding is about 1000 nHy, which provides only 60 ohm choking > impedance at 10 MHz. Sorry, but there are designs out there on the web > that do not hold up to scrutiny. > An effective balun must have a choking impedance of at least 5 times the > feedpoint impedance, so for a 4:1 balun (200 ohms), the impedance must > be 1000 ohms or more to be effective. > > 73, > Don w3FPR > > On 11/5/2012 2:16 PM, Randy Moore wrote: > > Can I divert slightly? I want to build this balun > > (http://www.combotec.com/projects/balun14/balun14.html) > > to use with a 40m delta loop from my K3/100, but the only PVC I have is > about 1.25" in diameter, not 40mm (1.5"). How do I compensate for the > smaller diameter? Google searches haven't been productive. > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
