What is a Ground Plane?

[WSEP819]

Newbie question here, but what is a Ground Plane in regards to antennas? What is it for, why is it important and any suggestions on a DIY ground plane for small homebase setup? Preferably mobile if possible.

[marcspaz]

An RF ground plane is a conductive surface that serves as a ground reference point for radio frequency signals in antennas. It provides an electromagnetic reflection of energy to complete a portion of a radiated signal.. and is often an electrical ground, as well.

[marcspaz]

8 minutes ago, WSEP819 said:

I am just using a midland MicroMobile MXAT04 6.6dB Gain Highland Tall Bullbar Antenna as a mobile basestation antenna.

My ignorance is showing. Just goes to show that I have alot more research to do. I appreciate the info and suggestions. If there are any other suggestions, I am all ears. Thanks all!

 

No one is born knowing anything. We all have to learn somehow. I'm glad you're here an asking questions. You are absolutely on the right track and asking the right questions. 

 

There are a bunch of ground plan kits for sale that are tripod mounted for portable and base station use, which sounds like what you really need. As someone mentioned earlier, you could also use a magnetic mount and a large (for stability) pie/cookie sheet as well.

 

Have fun! Experimenting and finding what works best is a big part of the fun for me.

[WSEP819]

So that makes sense when I heard some referring to the surface of their vehicles as a Ground Plane. What would you recommend for a Ground Plane size for the size of say, a 48 inch antenna that will be for a mobile homebase? Or is there more to it than that?

[marcspaz]

It varies based in antenna design and frequency.  If you have a wire/rod antenna that is a quarter wave length of the desired frequency, ideally a disc that is about 1/8th wave radius (1/4 wave diameter) at a 45⁰ downward angle (like a cone) would be good. The closer to perpendicular or parallel, the longer/wider the ground plane would need to be.

 

If you are using wire/rods for a ground plan, the length rules are the same, but the more elements you have, the better performance will be.

[WSEP819]

I am just using a midland MicroMobile MXAT04 6.6dB Gain Highland Tall Bullbar Antenna as a mobile basestation antenna.

My ignorance is showing. Just goes to show that I have alot more research to do. I appreciate the info and suggestions. If there are any other suggestions, I am all ears. Thanks all!

[TrikeRadio]

On 9/17/2024 at 9:24 AM, WSEP819 said:

So that makes sense when I heard some referring to the surface of their vehicles as a Ground Plane. What would you recommend for a Ground Plane size for the size of say, a 48 inch antenna that will be for a mobile homebase? Or is there more to it than that?

Here is what I use wtih a mobile antenna. Juse a metal pizza pan. (This was mostly and experiment using it indoors and it seems to put out a great signal to he repeater 24.5 miles away)

[wayoverthere]

On 9/17/2024 at 9:37 AM, WRXP381 said:

A cookie sheet or pizza sheet works wonders if you’re using a ground plane antenna at home.    What antena are you using at home that requires a ground plane. 

My base setup has been down for a bit due to rearranging rooms....prior to that I had a Midland mxta03 (the discontinued 3db whip) mag mounted to an 8"X12" piece of sheet metal on the top shelf of a closet.  Little to no simplex here, but it was sufficient to use the repeater 60ish miles out across the valley

[WSEP819]

9 hours ago, TrikeRadio said:

Here is what I use wtih a mobile antenna. Juse a metal pizza pan. (This was mostly and experiment using it indoors and it seems to put out a great signal to he repeater 24.5 miles away)

For a pizza pan, that looks like a clean set up. My granddad had his radio shack setup looking like a rats nest of cables.

[Socalgmrs]

A cookie sheet or pizza sheet works wonders if you’re using a ground plane antenna at home.    What antena are you using at home that requires a ground plane. 

[Socalgmrs]

4 minutes ago, WSEP819 said:

I am just using a midland MicroMobile MXAT04 6.6dB Gain Highland Tall Bullbar Antenna as a mobile basestation antenna.

My ignorance is showing. Just goes to show that I have alot more research to do. I appreciate the info and suggestions. If there are any other suggestions, I am all ears. Thanks all!

That’s a good antenna and it does not need a ground plane at all.  It is very me of the few mobile antennas that are designed to mount on a “bull bar” or roll cage or roof rack and has no need for a ground plane so don’t worry about it and run it.