Well skin effect varies with frequency, there for the R is higher with frequency. I is constant, but R is not, so your power lost will vary with frequency because of I^2R and skin effect. This is why larger diameter solid hardline has less loss than smaller.
On 8/26/07, Ron Wright <[EMAIL PROTECTED]> wrote: > > Jesse, > > You are correct and this is why some large coax have hollow tubing for the > inter conductor. Due to skin effect the current density on the outer part of > the conductor is higher. > > But if a coax has 10 watts with a said current at one freq and the same > current at a higher freq the losses will be different. This was my point. > > 73, ron, n9ee/r > > >From: Jesse Lloyd <[EMAIL PROTECTED] <ve7lyd%40gmail.com>> > >Date: 2007/08/26 Sun PM 02:34:41 CDT > >To: [email protected] <Repeater-Builder%40yahoogroups.com> > >Subject: Re: RE: [Repeater-Builder] Re: Duplexers > > > > > >I^2R losses do change with frequency because of the skin effect. > > > > > > > >On 8/26/07, Ron Wright <[EMAIL PROTECTED] <mccrpt%40verizon.net>> wrote: > > >Jeff, > > > >The low shield coverage is one reason I do not buy cables with > pre-installed connectors unless I know the cable...not just because it says > RG8 or whatever. > > > >I used a piece of 50 ft RS RG8 w/pre-installed connectors for a few years > and finally cut it for other purposes and was so disappointed I had > purchased such a cable with so little shield. > > > >Guess works for CB and Ham HF bands, but really not good for VHF/UHF. The > same can be said for many PL259 connectors and adapters. > > > >73, ron, n9ee/r > > > >>From: Jeff DePolo <[EMAIL PROTECTED] <jeff%40depolo.net>> > >>Date: 2007/08/26 Sun PM 12:59:45 CDT > >>To: [email protected]<Repeater-Builder%40yahoogroups.com> > >>Subject: RE: [Repeater-Builder] Re: Duplexers > > > >> > >>Coax leakage is different than currents flowing on the shield though... > >> > >>I remember having some RG8 from Radio Shack with braid openings that you > >>could probably fit a pencil through. > >> > >>> Some of the cheaper coax brands have less than about 70% shielding > >>> making them pretty leaky to rf. It works just killer for adding a > >>> little extra signal horse-power to a carrier current broadcast > >>> station. Radiax without trying... > >> > >>You could run it up the tower and have a really long antenna. Lots of > >>capture area ;-) > >> > >> > > > >Ron Wright, N9EE > >727-376-6575 > >MICRO COMPUTER CONCEPTS > >Owner 146.64 repeater Tampa Bay, FL > >No tone, all are welcome. > > > > > > > > Ron Wright, N9EE > 727-376-6575 > MICRO COMPUTER CONCEPTS > Owner 146.64 repeater Tampa Bay, FL > No tone, all are welcome. > > >
