Long wire matching devices.
Hello all, There are a couple of different impedance matching devices, (ununs), random wire, typically 9:1 impedance ratio, and EFLW types, Typically 64:1 or 49:1, which require resonant lengths. Most all are wound on toroidal cores, either powdered iron or ferrite. I have found that ferrite cores to perform the best, (type 43 for low bands and 61 for your high HF bands. I've also found you can fab simple ununs and baluns from ferrite beads. They can be wound as 9:1, with as little as 28" of wire. Dual ferrite beads fashioned binocular style, even single beads works well. Not to promote my brand, but, You can see them on eBay that I sell for cheap, or at least see how easy they are to make. Also sell toroid cored ones as well. 320 hams have bought, with good feedback on them. Search Duel Ferrite Bead 9:1 unun. to check out. Thanks for your indulgence. John, kg6zbn, (eddieson)
Hi John !
A lot of folks. Use 4:1 current Baluns for their dipoles fed with 450ohm ladder line. I am looking for one that can handle 1.5 KW that’s in a case. Do you sell something a long those lines ?
Thanks a lot !
Rod
Hello Rod. I'm getting ready to offer 4:1 baluns but not that high a power one. The required core is expensive (type 61), and would likely have to be stacked. If I can find some reasonably priced cores, I will get back with you. I want to try to keep it under $30. The cores I have found are that much alone! (for two) 73, John