----- Original Message ----- From: "Richard (Rick) Karlquist" <rich...@karlquist.com> To: <j...@audiosystemsgroup.com> Cc: <topband@contesting.com> Sent: Friday, July 13, 2012 9:46 PM Subject: Re: Topband: Mother of all ferrite common-mode coaxial chokes
> > Another thing you can do to measure chokes accurately is > to simply use a Vector Impedance Meter instead of a network > analyzer. Like the HP 4815A. In essence, it uses the VI > method, as the name implies. It doesn't care if the > impedance is nowhere near 50 ohms. For really high > impedances, it can be helpful to mathematically subtract > the stray capacitance of the probe. I've gotten excellent > results with my 4815 for years. > > Rick N6RK Thats what I used at work in the 80's to measure, seemed to correlate well with the expected attenuation. Ive also had one at home for about 20 years. Carl KM1H _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK