Home |
Search |
Today's Posts |
#1
![]() |
|||
|
|||
![]()
I can't find this in any of my books, so thought I ask the group:
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? Tnx, Bob k5qwg |
#2
![]() |
|||
|
|||
![]()
Bob Miller wrote:
I can't find this in any of my books, so thought I ask the group: 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? Tnx, Bob k5qwg This has been hashed over many times. A google search will provide all the details. Bottom line: If you want a DC ground, bare wire or bury your ground rod in a trench. If you want a RF ground, it doesn't matter. -- Jim Pennino Remove -spam-sux to reply. |
#3
![]() |
|||
|
|||
![]()
Why buy more wire ... don't you have a knife?
jw K9RZZ |
#4
![]() |
|||
|
|||
![]() |
#5
![]() |
|||
|
|||
![]()
On Sat, 17 Jul 2004 10:30:16 -0500, Bob Miller
wrote: 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? Hi Bob, 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 |
#6
![]() |
|||
|
|||
![]()
On Sun, 18 Jul 2004 04:13:37 GMT, Richard Clark
wrote: On Sat, 17 Jul 2004 10:30:16 -0500, Bob Miller wrote: 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? Hi Bob, 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. 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? Tnx to all who have replied so far... Bob k5qwg 73's Richard Clark, KB7QHC |
#7
![]() |
|||
|
|||
![]()
On Sun, 18 Jul 2004 07:56:32 -0500, Bob Miller
wrote: 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, The Safety ground as RF ground will be ONE radial equal in path to all copper it is connected to (your plumbing in other words, provided it is not plastic) - not bad, but not any great shakes. It was never designed nor installed to serve RF, just to keep 60Hz tamed around home, shop and garden. You can build a separate Safety ground into your antenna ground system, but code demands you then connect both Safety grounds (to keep you, children, small animals, and your neighbors alive - this is not just a tedious bureaucratic exercise). The wire between them must be continuous (no splices). This also has the added advantage of cutting down on nasty noise problems called "ground loops" (the hum that refuses to go away or the strange operation of other electronics while you are transmitting). 73's Richard Clark, KB7QHC |
#8
![]() |
|||
|
|||
![]()
Reminds me of the cartoon of the lineman whose job changed to running
underground service - he said the hardest part was getting the holes deep enough to bury the power poles. You got a lot of good advice already - I vote for bare copper - and use the ground rod and its ground clamp as a solderless lug to distribute the buried ground wires. "Bob Miller" wrote in message ... I can't find this in any of my books, so thought I ask the group: 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? Tnx, Bob k5qwg --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.721 / Virus Database: 477 - Release Date: 7/16/2004 |
#9
![]() |
|||
|
|||
![]()
"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 |
#10
![]() |
|||
|
|||
![]()
"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 |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Inverted ground plane antenna: compared with normal GP and low dipole. | Antenna | |||
Adding lengths to bare wire antenna? | Antenna | |||
QST Article: An Easy to Build, Dual-Band Collinear Antenna | Antenna |