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Attic antenna grounding, balun and coax looping questions



I recently purchased a Retevis RT97 bundle that came with a MA02 Antenna.  For a variety of reasons, I could not mount the antenna on the exterior of my house and have it in the attic with the tip of the antenna probably 8 inches from touching the peak of the roof.  I'm guessing the base of the antenna is about 25-30 feet or so the ground.  I used 50 feet of LM240 and have at least 7 feet of slack or more.  The roof decking is pine and I have a traditional asphalt based shingle with no metal foil back decking material to interfere with transmissions. 

I realize I'm losing efficiency with the attic mount, but I have no other option at the moment.  My immediate goal is to provide coverage of 1 to 2 miles around my home. 

I have the coax directly connected to the antenna with no balun or coax loop and am getting a SWR of about 1.2. 


1) Do I need to worry about grounding the antenna being that it's an attic mount?

2) I have slack to make several loops of the coax at the base of the antenna. However, I've read conflicting advice as to whether this is necessary or even all that effective. looking for advice and comments on adding a coax loop and if so, how many loops?  Does the size of the loop matter?

3) Balun - I have read enough to generally understand what a balun does, but everything I've read seems to be related to a use of a balun for a true resonant dipole. several of the videos I watched had true dipole set ups and in looking at online sources for buying baluns all of the options I've seen seem to have the coax connections and then two terminals for connecting the dipole elements. 

Do I need a balun for my set up and if so, what kind and how would it be attached to my particular antenna?

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No Balun needed. No loops needed. As said use it. If you find you are having trouble with coverage upgrade your cable to LMR400. LMR240 is about 5.25db loss per hundred so you have maybe 2.6 db of loss. Should not be noticeable for our current situation. LMR would effectively cut that in half. 

I would not worry about grounds in the attic. I have a few antenna's in the attic and they work fine. 

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