Jim wrote: WRONG! There are three fundamental cases of ferrite "baluns" or chokes. 1) A
choke wound with coax 2) a choke wound with parallel wires (bifilar) 3) a transformer (voltage balun). ----------------------------- You are absolutely right Jim. I read current balun and thought choke balun. I missed the 4:1 comment. "Balun" is an unfortunate, all-inclusive and misleading term. One so-called "balun" may be as different from another "balun" in its requirements and application as a motorcycle is different from railroad locomotive. I stand by my statement when talking about a "choke balun" consisting of a string of ferrite beads on some coax or a coaxial line on a coil form such as I described. The only losses caused by such a balun will be those of the transmission line itself, which cannot be ignored if the SWR is high. So-called "baluns" that transform impedances are, typically, transformers -- often transmission-line transformers. They're a whole different animal and can be very unpredictable, especially when they use ferrite or powdered iron cores and are exposed to a wide range of impedances. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
