Some thoughts or advice on antenna location and grounding requested.....

[WVdogman]

Hello everyone. I'm new on here on just purchased a BCD996XT. I am considering purchasing an omni directional antenna and keeping it in the attic in lieu of mounting it outside. I was curious about the need to ground the antenna if it is indoors and if so does anyone have any advice as to the best way to ground it would be. I live in Berkely County West Virginia. Any advice would be most appreciated. Thanks in advance.

[GrumpyGuard]

If you are placing the antenna in the attic you don't need to ground it. If you are setting up an antenna that has radial elements around the base they will make up your ground plane.

[mmckenna]

For an RF ground plane, GrumpyGuard is correct. For lightning protection, you should ground your antenna and install the appropriate type of protection on your feedline. Induced current from a nearby lightning strike can still damage your equipment. A well grounded antenna can also help reduce some noise.
From a just getting started point of view, just about anything will be better than the stock antennas. The attic is a pretty safe place, but unless you have a steel roof, (and even then) you are at risk for induced energy.

[WVdogman]

Thanks Grumpy and mmckenna for the advcie. I'm thinking of a wideband discone antenna and using LMR-400 coax cable as the line feed. Would that cable have the appropriate protectection that you are speaking of?

[mmckenna]

No, the cable itself will not have any protection.

What you should do at a minimum is ground the mount for the antenna to a metal cold water pipe, or better yet, use a ground rod. By grounding the antenna base, you would also ground the outer shield of the coaxial cable.
Ideally you would want a supressor on the feed line. Something like a polyphaser device would help protect your equipment, but to be on the safe side, you should disconnect your scanner when not using it, or when storms kick up in your area.

LMR-400 and a discone would work well, however don't overlook some of the multi-band vertical antennas out there. Discones work well at covering a lot of frequenices, but don't necessarily do it well. They are sort of on one side of the compromise spectrum.

There are entire books written on grounding systems, way more than I could type here. There are a lot of fine details that go into the area of the National Electric Code. You really need to do some research here.

What I can tell you about antenna systems is that you get out of them what you put in. If you cut corners on your antenna system, your system will suffer as a whole.

[BorderPhD]

I thought about using an external mobile type scanner antenna. probably mount it on the roof of my house. this would have to be superior to the regular telescoping antenna on my Pro 197, correct? I assume I would need to ground it somehow?

[WA0CBW]

A mobile antenna uses the car body as a ground plane. If you put a mobile antenna on the roof you will need to create that ground plane. It can be as simple a 4 rods 1/4 wavelength long at the lowest frequency you want to listen to. These four radials should be connected to the shield of the coax at the antenna (the ground side of the antenna). They form an RF ground plane and are effectively the other half of the antenna.

As mentioned above the shield of the coax should be connected to a ground rod. There are some electrical code rules about connecting and installing ground rods that you should research as every installation is different.

BB