| Author |
Message |
    
Doggie619
Junior Member
Username: Doggie619
Post Number: 12
Registered: 2-2005
| | Posted on Friday, April 08, 2005 - 7:02 am: | 
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ive got a imax 2000 antenna and was wondering if i should run a ground wire from the antenna mounting plate or just grounding the mast is good or do both. |
Tech808
Moderator
Username: Tech808
Post Number: 5482
Registered: 8-2002
| | Posted on Friday, April 08, 2005 - 7:11 am: |
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Doogie619,
Ground the mast pipe to the tower and ground the tower to a 8 or 10 foot copper or copper clad ground rod. 
Lon
Tech808
CEF808
N9OSN |
Kj7gs
Junior Member
Username: Kj7gs
Post Number: 24
Registered: 12-2004
| | Posted on Friday, April 08, 2005 - 9:13 pm: |
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If your tower is going to attract lightning, you may want to go with more than just one ground rod. |
Starface
Junior Member
Username: Starface
Post Number: 25
Registered: 1-2005
| | Posted on Thursday, April 21, 2005 - 9:38 pm: |
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I have found this works good for me.
1.buy C70-05014 COAX CONN 83-23 LIGHT. ARRESTO
from COPPER $ 4.99 This hooks into the COAX CONN SO-239 of the antenna and your PL-259 Coax Connector hooks into the other end.
2.hook a 14g to 16g solid cooper wire to the C70-05014 COAX CONN 83-23 LIGHT. ARRESTO and run the wire down the tower/mast to a mast grounding clamp
and hook the wire to that clamp.
3. Now useing the same clamp on the mast or tower leg put another heavy G copper wire from that clamp to a grounding clamp on a 8-10 foot urbar grounding rod.
hope this helps
CEF#476
Starface
Auburndale, Florida |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 349
Registered: 7-2004
| | Posted on Friday, April 22, 2005 - 3:27 pm: |
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Starface: I use the C70-05014 all over the place and provide a RF ground.
Back of the Amp, back of the radio, antenna base/coax connection.
I also solder the connectors to the wire ends, instead of just crimping them on.
I also grounded the mast to the rebar.
This did away with a significant amount of "white noise" as well. |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 429
Registered: 9-2004
| | Posted on Sunday, April 24, 2005 - 1:18 am: |
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doggie619, i think these well meaning gentlemen are misunderstanding your question a bit.
from what i gather, you have your IMAX mounted on a metal pole.
to answer your qusetion definitively; no, you do not need to run an additional ground wire from the plate to your ground rod. if you did you would probably pick up more noise and bleed on the neighbors more. think of your mast as a really big ground wire. as long as you have a good metal to metal connection from the plate to the mast you're fine. (use some "ox guard" from lowe's on the bolts and the plate. this keeps the metal from oxidizing.)
now for some additional stuff.
does your mast fo all the way to the ground?
if so, maske sure all the mast sections are electrically connected well. meaning that the paint is ground off and there is a solid metal to metal contact. now use as big a size of wire as you can find to connect the bottom of your mast to a ground rod pounded all the way into the ground preferably right next to the mast. no matter what, keep any ground wires less than 8 feet long. keep them 1 foot long if possible.
if your mast doesnt go all the way to the ground; you need to find a ground wire that is 2ga. or bigger and run it from the base of your mast to your ground rod. DO NOT CONNECT THIS GROUND WIRE TO THE COLD WATER PIPE/AC GROUND FOR YOUR HOUSE. this will cause all kinds of havoc.
matt |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 366
Registered: 7-2004
| | Posted on Sunday, April 24, 2005 - 11:54 pm: |
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Kid... Cold water pipes? LOL.....
You are correct, PVC is never much of a ground! |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 430
Registered: 9-2004
| | Posted on Monday, April 25, 2005 - 10:05 pm: |
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hey!
depnding on when your house was built; you probably have copper water pipes, and the electrical system for your house is probably grounded to them. check near your water heater. you just may find a clamp with a copper wire attatched to it.
grounding your antenna to this ground is not a good idea.
wait, you were messing with me weren't you.
darn!
matt |
Crackerjack
Intermediate Member
Username: Crackerjack
Post Number: 371
Registered: 7-2004
| | Posted on Monday, April 25, 2005 - 10:49 pm: |
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That's my point, copper pipes are not that common any more.
That said, even so -the "house ground", however it is achieved, is seldome adequate for RF Ground.
I would like to have a MFJ Artificial Ground unit that tunes the ground =connected to a very long rebar bamged into the ground, just outside less than 4 feet away.
I have done that and will pick up an "AG" unit someday, I think my rebar goes down 10 feet. |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 432
Registered: 9-2004
| | Posted on Monday, April 25, 2005 - 11:19 pm: |
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you probably dont want to hear this, but rebar doesnt make a very good ground rod. if you look up a table on conductivity of various metals, you will see that steel is far removed from copper and aluminum when it comes to conductivity.
maybe ok for AC ground but not for RF.
matt |
