simple antenna question multiple antennas.

[tknjk]

Basically I installed a discone antenna on my roof. I used a 5' mast, and my peak on the roof is about 25' so the antenna is about 30' in the air. Works great getting awesome range on my scanner. Picking up things I never could before, and clear as a bell.

I want to install 2 more antennas. a CB antenna, and some sort of other antenna for my baofeng UV-5R, and for whatever radio I decide to buy after I get my license.

is there a distance I need to be mindful of when installing other antennas. Will they interfere with each other? Any advice will be appreciated. Thanks.

 

[LtDoc]

The quick-n-dirty answer is to keep antennas as far apart as possible/practical. If any two or more antennas can 'wiggle' and touch each other, then that's too close. After that it's a matter of what's practical for you. Any two or more antennas 'near' each other will affect each other. How much? Depends on how they are harmonically related. Same band means problems of various sorts. There's just no definite answer to that question, sorry...
- 'Doc

 

[tknjk]

Well for right now I just want a CB to go up with my Discone. I have read it's better to place them vertically rather than horizontally. It that's the case my plan is to mount a horizontal arm and then 2 uprights, with the taller of the 2 having the CB antenna, and the shorter just under, and about 4 feet away having the discone for UHF/VHF/Scanning.

 

[davenlr]

As a rule of thumb, its best to keep the antennas at least one wavelength (of the lowest antennas frequency) away from another antenna, or from any metal, coax, downspouts, etc unless the antennas are being used in a stacking arrangement. I.E. a CB antenna 9 ft away from the discone would probably not cause any issues with the discone, but the discone and its mast would probably affect the CB antenna... Since its hard to keep anything 36' away from the CB antenna, you could just make sure its base is higher than other antennas on the roof.

 

[tknjk]

I wish that were possible. The only way I can arrange them is stacked. Guess I'll have to try it out and see. Thanks.