Re: Q about balanced feed line

Hi Roy,

I have a couple of RF current meters with freq. response from 10KHz to 100MHZ that are the types used for FCC part 15, DO-160E testing etc. and have a transfer impedance of 0dB-ohm. They have an opening of about 1.6" dia. and I sqeeze the feedline together (spacing about 1.5") temporarily and clamp over both conductors for measurement #1 and clamp over just 1 of the conductors for measurement #2. I read the output of the current probe with an RF power meter. In my case the current in a single conductor was approximately 15dB above the differential current which seemed to be pretty well balanced. Is there anything wrong with this approach?

Larry Benko, W0QE


Roy Lewallen wrote:
Amos Keag wrote:


YEP!!

An RF Ammeter will do just fine


Balance requires that the currents in the two wires be equal in magnitude and opposite in phase (or direction). How do you connect an RF ammeter to determine this?

Roy Lewallen, W7EL
.

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