Robert11 wrote:
Hello,

First, let me say thanks to everyone for the replies and help.
New at this, and it seems these very basic questions of mine keep coming up
the more I look into it.
Great hobby, and really do appreciate the help, very much.
Super newsgroup for folks like me. Sure is a lot to learn re antennas;
reading the ARRL book on it now.

Would like to modify my question somewhat.
Was really surprised to learn about the copper on steel, vs all copper
center conductors on coax.
I thought the difference were only in types of shielding; not center
conductor construction, and that RG6, e.g., was RG6, at least concerning
attenuation and perhaps "quality". Guess not ?

I understand, and am aware of now, the skin effect depth
Will read up on it some more.

Question: any meaningful difference for the sw frequencies; say from 0.5 to
30 MHz ?
I have a sw receiving set also, and frankly, when i strung my coax for it, I
never considered the center conductor coax's construction.

Should I have, possibly ?

Thanks again,
Bob

Any quality coax will have a sufficiently thick copper coating on the
center conductor to insure that the current is, for practical purposes,
always in the copper rather than the steel down to quite a low
frequency. If the plating were unusually thin, the current would
penetrate into the steel at lower frequencies and the loss would be much
greater. However, loss in a transmission line used for receiving only
becomes very much less important at HF and below (that is, below about
30 MHz). So the bottom line is that it's not normally anything you need
to worry about.

A copper plated steel conductor is used to increase the physical
strength of the cable, particularly cables of smaller diameter and
higher impedance, where the diameter of the center conductor becomes
small. When done properly (as it usually is), it works just the same
electrically as a solid copper conductor.

The _ARRL Antenna Book_ is a very good place to start in learning about
antennas.

Roy Lewallen, W7EL