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legal height for 10/12 meter base antennas ?

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BOOTY MONSTER

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according to the FCC , whats the maximum legal height for a base antenna on 10/12 meters ? and is it different if its attached to a house/structure vs. a free standing tower ?

just curious.......
 

BOOTY MONSTER said:
according to the FCC , whats the maximum legal height for a base antenna on 10/12 meters ? and is it different if its attached to a house/structure vs. a free standing tower ?

just curious.......
Click to expand...


Part 95 - Subpart D - Rules for CB Service
Citizens Band (CB) Radio Service

​
{A} "Antenna" means the radiating system (for transmitting, receiving or both) and the structure holding it up (tower, pole or mast). It also means everything else attached to the radiating system and the structure.
{B} If your antenna is mounted on a hand-held portable unit, none of the following limitations apply;
{C} If your antenna is installed at a fixed location (whether receiving, transmitting or both) it must comply with EITHER one of the following:
[1] The highest point must not be more than 20 feet (6.10 meters) higher than the highest point of the building or tree on which it is mounted;
or
[2] The highest point must not be more than 60 feet (18.3 meters) above the ground.
{D} If your CB station is located near an airport, and if your antenna structure is more than 20 feet (6.10 meters) high, you may have to obey additional restrictions. The highest point of your antenna must not exceed 39.37 inches (1 meter) above the airport elevation for every 109.36 yards (100 meters, 1 hectometer) of distance from the nearest point of the nearest airport runway. Differences in ground elevation between your antenna and the airport runway may complicate this formula. If your CB station is near an airport, you may contact the nearest FCC field office for a worksheet to help you figure the maximum allowable height for your antenna
 
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thanks imd262 . i already know the legal height for a cb base antenna . i was curious if going to ham use bands/frequency's allowed a higher antenna tip .
not that i can afford to go higher than 60ft myself ....... just wanted to know for future reference .

thanks again though .:thumbup1:
 
I believe its 200 feet to the highest point of the antenna unless your near an airport then other restrictions may apply.
 
My beam at 100 feet is plenty but Im also on a 60 foot hill. My Antron 99 is on the roof with a tripod and I use that from 17 - 10 meters and it works fine. My Comet GP-3 dual band 2meter - 70cm antenna is on a chimney strap and also get out great. My inverted V works great aswell and the apex or top is at about 50 foot or so off my tower and it gets to who I want it to. I have thought about adding some extra sections of tower here but see no point as Im happy with it and I would have to add more guy wires if I go higher.

As mentioned once you start getting to commercial heights then lights are required along with FCC approvals.
 
Yes booty it is 200' after that need to have light on top there are some who have 300' plus towers.

I keep mine at 70 to 80 feet, works great for 40 meters and above, any lower band the antenna is just a cloud warmer. That is where the ground mounted verticals come in for long distance
DX.
 
Very basically, there is no maximum height for amateur antennas on any band. There are restrictions though. Those restrictions deal with proximity to airports. Over a particular height (200 feet) the tower/structure has to be made visible, has to have a light(s) of a particular kind on it. That's for aircraft safety. And there's a rule about height versus distance from an airport, so much height for measured distance from that airport. After that there are no restrictions, except in very special circumstances, as far as the -FCC- is concerned. There are other restrictions! But, those restrictions are from authority other than the typically thought of federal government. Most of those deal with 'practical' aspects.
- 'Doc
 
BOOTY MONSTER said:
not that i can afford to go higher than 60ft myself .......
Click to expand...
I had every intention of taking this beam I'm working on to 80', you know the 2 wavelength thing, and I still may later on after I get it up and working at 60'.

But, depending on how much faith you have in modeling programs, things really start to slow down after 60'. I modeled it from 30' to 100' in 10' increments and while there was still an advantage after passing the 60' mark, it was small compared to gains below the 60' mark. Diminishing returns, yanno.
 
If you've got the space, hitting the 200 ft market isn't hard. Rohn 45g are under $300 per 10 ft section. Add a couple miles of guywire, and you've got a godlike setup for all bands.

Load the tower up for 80m or 160m, and work some DX. :D
 
359 said:
I had every intention of taking this beam I'm working on to 80', you know the 2 wavelength thing, and I still may later on after I get it up and working at 60'.

But, depending on how much faith you have in modeling programs, things really start to slow down after 60'. I modeled it from 30' to 100' in 10' increments and while there was still an advantage after passing the 60' mark, it was small compared to gains below the 60' mark. Diminishing returns, yanno.
Click to expand...


While the gain may show diminishing returns you will still get a larger shot at the horizon with more height. It will also put your RF further away from neighbors.
 
Here's the Part 97 requirement:
Section
This includes the famous "PRB-1" notice that says states and other municipalities have to make provision for radio operators ... BUT Homeowners Associations are private entities and aren't required to pay any attention to PRB-1.

Then, as you'll notice, you may have to comply with Part 17. I'll leave it up to you to find that.
 
Kamikaze said:
While the gain may show diminishing returns you will still get a larger shot at the horizon with more height. It will also put your RF further away from neighbors.
Click to expand...

I agree. Even though the bottom lobe stops dropping so quickly after 60', it still sees the horizon better which can't be truly modeled.
 

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