I think we're talking apples and oranges here. A hollow waveguide of a specific dimension does have a low-frequency cutoff point, below which a wave cannot propagate through its length. But, a coaxial cable is not a waveguide, and it does not have a low-frequency cutoff.
73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Jeff DePolo Sent: Sunday, September 02, 2007 7:01 AM To: Repeater-Builder@yahoogroups.com Subject: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers <major snip> > There is a point at which it starts to > propergate and does look like 75 Ohms. I think you might > understand this. I'm not trying to rake you over the coals Ron, but I *am* trying to prove a point: there is no low-frequency cutoff for coaxial cable, period. You may experience (or even measure) behavior at very low frequencies when the cable is a small fraction of an electrical wavelength that might make you want to think otherwise, but it's not due to transmission line theory, math, or physics breaking down at some low-frequency cutoff. --- Jeff
