A nanoVNA is an incredibly capable, versatile, and inexpensive instrument (<$100) that can make these measurements when using proper technique and analysis. They also work great as graphical antenna analyzers.
Lou W7HV On Friday, October 22, 2021, 05:52:20 AM MDT, John Oppenheimer <j...@kn5l.net> wrote: Hi Mike, Initial permeability can be computed from your values: Compute 4T permeability=1 (Lo) using core dimensions: Lo = 0.0004606 * Log10(OD / ID) * Ht * Turns^2 (Ht in mm) Lo = 0.0004606 * Log10(6 / 2.6) * 14.3 * 16 = 0.0383uH (Ht in mm) Initial Permeability ui = 6.6 / 0.0383 = 172 Fair-Rite 61 material ui = 125, 52 material ui = 250. If characteristics are close to 61 or 52 material, then could use it for an HF Choke Balun. Complex permeability can be plotted out to 20 to 30 MHz range using a single port VNA. Do you have a VNA? I can walk your through the process if wanted. John KN5L On 10/21/21 1:24 PM, Mike Maloney wrote: > We were gifted a somewhat large (6"OD, 2.6" ID, 9/16" thick) ferrite core of > unknown mix and original use. On face was marked 6.6uH w/4turns. My > thinking it might make a good common mode RF choke on the output of an > inverter generator or on coax feedline. Not familiar with properties of > toroid cores of this size. Any ideas? > 73, Mike AC5P ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to louand...@yahoo.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com