Grounding and Homemade antenna's.

[triggerhappy2006]

Okay so I apologize first off if this question has been answered already but I did search the forum and google first.

So I read on another site (eham) that the braid of coax can be used to ground an antenna (electrical ground) via grounding rod. Which confuses me a bit because in the case of a homemade Dipole, the braid is connected to one element and the center conductor is connected to the other half. Maybe I'm completely lost but it seems to me if you let the braiding come in contact with the tower you will essentially be turning the tower into half of your antenna?

WX7G
Member

RE: Grounding a wire dipole antenna?
« Reply #1 on: April 02, 2010, 06:27:51 AM »

Maximum lightning protection will be achieved with a lightning ground below the dipole (connected to the coax shield), grounding the coax shield at the AC service entrance, and installing an arrester at the AC service entrance.

RE: Grounding a wire dipole antenna?
« Reply #9 on: April 02, 2010, 11:55:23 AM »

Regarding the original question posted here, yes, it is common practice in the Telecommunications Industry to bond the shield side of the feedline to the tower at several points such as top, middle, and bottom of the cable run if the tower is tall. This is assuming that the tower is well grounded. This is primarily done with heliax cable but the same principle applies to any coaxial cable.

Ed K7AAT

 

[Beetle]

A dipole is a "balanced" antenna and does not need any sort of ground to work just fine.

Other types of antennas may require grounding, but usually that's in the form of an RF ground or counterpoise, which in fact DOES take the place of the "missing" portion of the antenna. You didn't specify what type of antenna you're asking about.

There are three types of "grounding": Safety, Lightning and RF. Different functions, different methods.

 

[longhaireddwb]

The grounding that they are talking about using the coax braid as a strap is to ground your tower or push-up pole to earth. Using a ground rod. As was already stated, if your using a dipole then your antenna don't need grounding to earth as like you said, that will cause problems.

Hope this help to clear things up.

 

[Captain Kilowatt]

Think about this. The radio end of the coax cable IS GROUNDED ALREADY even if it is connected to a dipole. If a lightning arrestor is installed in that coax cable line then it is grounded at another point as well. What harm will one more point do.

 

[triggerhappy2006]

There are three types of "grounding": Safety, Lightning and RF. Different functions, different methods.

Question on this, Safety I'm guessing is related to the risks in relation to TX'ing on an antenna. Lightning is obvious enough, allow any direct lightning hit to travel through the antenna to a lightning arrestor and discharge the hit to the ground. and RF would be for alternative antenna types that require grounding?

Second, I saw a mention of .........disregard I found the ARRL lightning protection section......jesus I'm blind.