Bob, K5QWG wrote:
"Or should I go buy some bare solid copper wire?"

Depends on frequency. As a path for electricity, the earth is like a
leaky capacitor or a good capacitor in parallel with a resistance.

Terman says on page 807 of his 1955 edition:
"At broadcast (550-1600 KHz) and lower frequencies the ratio of
capacitive reactance of the earth to the earth resitivity (sigma
reciprocal=1/conductivity) is considerably greater than unity, so to a
first approximation the earth can be considered as purely
resistive.----Conversely at frequencies of the order of 10 MHz and
greater, the impedance represented by ground (not sea water) is
primarily capacitive, and ground-wave attenuation at a given physical
distance is determined by the factor of frequency divided by the
dielectric constant plus 1."

So for low frequencies use bare wire. For high frequencies, you won`t
notice insulation on your radials, electrically.

Best regards, Richard Harrison, KB5WZI

"Bob Miller" wrote

For my general station ground, I have a copper pipe that goes down
about one foot -- then hits rock or limestone or whatever.

I'd like to enhance the pipe with a few buried radials. I happen to
have a 500' roll of 14-guage stranded *insulated* copper wire. Will
the insulation keep the wire from becoming "one with the dirt"?

Or should I go buy some bare solid copper wire?
---
and then Bob added:

Question -- is there a problem in using a safety ground as an rf
ground, too? If I connected 10x50-ft bare, buried radials to my little
pipe, and used it as a safety ground for the station, and also as a
ground to work an inverted "L" against, would that be a problem, or
should I have separate ground points?
--

Hi Bob, can you be more clear on what you meant by "general station ground"?

Since you're in thunderstorm country it could be you mean a lightning
protection ground. But you also mention safety ground and RF ground so it
appears you have multiple requirements here.

Conductor choices vary according to the function of the system so it is
difficult to generalize about stranded v. solid wire until you can be more
specific in your requirements. In some cases neither kind of wire is
appropriate, with wide/heavy gage copper strap being the best choice.

However many purposes your ground system fulfills, and from however many
places it connects to ground rods, one standard always applies: you must
always bond all of your earth-references (ground rods) to your station
equipment AND the main entrance ground of utility wires coming into your
home. Preferably that station single point ground and the Utility single
point ground are the same place. Unfortunately few of us are so lucky as to
be able to locate our station right at the main Utility service entrance.
When the two are far apart that creates problems. With a lot of help from
this group, and professional engineer review, I completed a station
grounding and lightning protection system that accounted for those problems.
The complete site construction plans are listed at:
http://members.cox.net/pc-usa/station/grounding.htm

Hope this helps,

Jack Painter
Virginia Beach, VA

On Sun, 18 Jul 2004 04:13:37 GMT, Richard Clark
wrote:

Insulated will make a poor 60Hz safety ground (which you should
connect this ground to anyway). Insulated wire will make a perfectly
good RF ground (upwards to 5 orders of magnitude frequency shift makes
a considerable difference in what ground "means"). The pipe, on the
other hand, serves very little purpose. It is inadequate for a safety
ground, and useless for RF and maybe just suitable for providing a
mast base. It does give you a physical reference point - kinda like a
big solder lug.

Use up all your wire and enjoy - another 500 or 5000 feet won't bring
as much return as the first 500. For radials, try 10 X 50 feet, or 50
X 10 feet or something in between.
73's
Richard Clark, KB7QHC

My server will not download the reply I made to this post. Ater new posts
appeared and mine did not, I resent (twice). I understand they all did post,
and I apologize for resending what was already there. If anyone knows what
setting could be casuing them to be invisible (to me) I would appreciate
learning how to fix it. Even deleting the entire group and downloading all
headers and message bodies did not show my posts in this thread.

Best regards, and maybe someone could reply to this invisible-to-me post,
LOL.

Jack

On Mon, 19 Jul 2004 19:52:18 -0400, "Jack Painter"
wrote:

My server will not download the reply I made to this post. Ater new posts
appeared and mine did not, I resent (twice). I understand they all did post,
and I apologize for resending what was already there. If anyone knows what
setting could be casuing them to be invisible (to me) I would appreciate
learning how to fix it. Even deleting the entire group and downloading all
headers and message bodies did not show my posts in this thread.

Best regards, and maybe someone could reply to this invisible-to-me post,
LOL.

Jack


All your posts showed up this afternoon/evening (Monday). Been looking
at your website on grounding. Very informative.

thanks,

bob
k5qwg

Jack Painter wrote:
My server will not download the reply I made to this post. Ater new posts
appeared and mine did not, I resent (twice). I understand they all did post,
and I apologize for resending what was already there. If anyone knows what
setting could be casuing them to be invisible (to me) I would appreciate
learning how to fix it. Even deleting the entire group and downloading all
headers and message bodies did not show my posts in this thread.

Best regards, and maybe someone could reply to this invisible-to-me post,
LOL.

Jack

Everything depends on your news server. When you post a message it is
cued for posting with all the other current postings. Depending on how
busy the server is, it may not be able to process new postings until it
expires a bunch of old ones, to make space. Then it processes latest
postings and sends it's information off to other servers for posting.
The other servers have the same thing to deal with. If they are busy
they may even refuse a packet of postings and your server would have
to try again later.

My news server is somewhat local to me and I see my postings within
a few seconds of posting. But there are some news servers where I won't
be able to see my post show up for 6 or 7 hours. Google groups is like
this.

I just take it on faith that my posting got out. Even when I see it on
my news server, I have no idea when it will reach any of the other
servers.

--
Martin E. Meserve

http://www.k7mem.150m.com