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
