Ground plane question

[mnfeo2]

Can ground planes from different antennas overlap?

 

[SunTzuNephew]

Sure. It happens ALL the time.

 

[luckyrxc]

Ground Planes

Yup. If not we'd really be in each other's personal space!

 

[mnfeo2]

Sweet, thanks guys!

 

[ntsqd]

Extending on this, minimum spacing between two antennas would be?

My SOP guess would be the radial length of the largest ground plane would be the ideal minimum, but how much closer can they be?

 

[SunTzuNephew]

Extending on this, minimum spacing between two antennas would be?

My SOP guess would be the radial length of the largest ground plane would be the ideal minimum, but how much closer can they be?

My personal minimum is 18"

 

[luckyrxc]

Ground Plane

You can have them pretty close so long as they are not designed to work together, such as in the case of a semi running two cb antennas in tandem.

Consider an antenna tower in a Ham's back yard or a repeater tower on a mountain. They hang antennas all over it.


Can you describe your application?

 

[soonenough]

Extending on this, minimum spacing between two antennas would be?

My SOP guess would be the radial length of the largest ground plane would be the ideal minimum, but how much closer can they be?

Not sure what frequency we're talking about, but for CB I'm pretty sure it's 1/4-wave apart (i.e. ~8'). Which is why I always laugh when I see guys with two CB antennas on their trucks only 2 or 3 feet apart; I doubt that's doing a whole lot.

 

[luckyrxc]

precisely

Not sure what frequency we're talking about, but for CB I'm pretty sure it's 1/4-wave apart (i.e. ~8'). Which is why I always laugh when I see guys with two CB antennas on their trucks only 2 or 3 feet apart; I doubt that's doing a whole lot.

Exactly. As I understand it, hanging them on the left and right antenna's on a semi is still too close but everyone does it. The ideal application is on an RV or bus where you can have them on in front of each other, properly spaced. Also, as the vehicle you are communicating with goes by in the opposite direction on the drivers side, you lose half the loop because it is blocked by 50' of metal trailer.

 

[ntsqd]

I was more curious than had a direct application, but the most likely scenario for me would be a 2M and a cb antenna on the same vehicle.

 

[luckyrxc]

2M and CB

You're in business. I've done it many a time along with running 70 cm at the same time. Sometimes I'd use a dual band antenna and other times I would use two separate antennas for 2M and 440. Many folks do those three plus HF.

The fellow's post above says minimum 18". I've always just spaced them as the vehicle allows.