Radio towers and tv towers?

I believe the tower colors are an FCC or FAA regulation for aircraft, depending on the hight of the tower. I may be wrong on this though, this also goes with strobe lights on them, which is part of a migratory bird issue being studied.

As for putting a cell on a radio antenna, as long as it doesn't interfere with either frequency, they can do it.

As for the difference between TV & Radio towers, I can't help you there.

 

sometimes it makes no sense. I know of one cellular tower that is maybe 20 or 30 feet tall, yet it is painted orange and white.

-Jay

 

I think the large towers you see lined up in rows are AM radio.

I'm sure somebody else can provide much better explanations.

Anyway, here's a link to a really interesting site for photos of broadcast "tower farms" across the country. It incudes photos from tower sites, the Empire State building, Pudential Bldg, and the WTC.

http://www.fybush.com/siteindex.html

 

The main difference between a tv and radion tower is that most radio towers are guyed and are in the county will many tv antennas are lattice and close to the station. I have seen some cable towers that are guyed but that is a little more rare because of the micowave dishes that have to be put up. You can put cell equipment on either site if the structural will hold up and the price is right, which is rare.

The main problem with most radio towers is that they have AM on the tower which causes problems with the cell signal and makes it have to de- tune. That is the general rule of thumb.

 

So that towers are more visible to aircraft, they are painted or lit according to their height. Towers less than 1000 feet tall must be painted aviation orange and white- and must have red blinking lights at night. Towers over 1000 feet tall don't need the paint job but must have strobe lights on.

 

Towers must have aircraft obstruction markings if they are taller than 200 feet, or are near certain types of airports, including all public and general aviation airports, and including some heliports, seaplane ports, glideslopes, etc...

The most common markings are a) red lights and aviation orange / white paint, b) red lights for nighttime, c) white strobes 24/7, and d) dual lights (reds and strobes).

The FCC has unqualified authority over painting and lighting of communications towers but almost always issues specifications in accordance with those published by the FAA. The FCC routinely requires lighting on some towers not otherwise candidates for lighting, at the request of Sheriff's helicopter units, etc... These are often found near major highways.

As for AM radio, the tower itself IS the antenna. (FYI: This is also the case with the older LORAN stations.) Some AM's have directional patterns, and this usually requires more tower (i.e, more elements in the antenna array). It's just that the wavelengths are so long, you'd need a tower to support the elements, so why not use the tower as the element? (Hope that made sense!)

If you want to see a weird antenna, Google "Pusher antenna". The point being, antennas come in all shapes and sizes, but your typical cellular, PCS, FM or TV antenna will roost on a tower, or perhaps a building rooftop.

To correct something Carynvz wrote, tower less than 1,000 feet tall can be either painted orange/white with red lights alone, or with reds (night) and strobes (day). They can also be unpainted, in which case they MUST be equipped with strobes operating 24/7.

Similarly, towers taller than 1,000 feet can still be required to be painted orange/white.
There is nothing magical about 1,000 feet. Usually, if a tower is strobed 24/7, it doesn't have to be painted to be visible during the day. Since painting & paint maintenance is expensive, you'll often find that strobed towers are not painted. (But it has nothing to do with the height.)

Finally, to your question about towers in proximity to other towers -- if it's an AM station, it may be that all of the towers are actually the AM's directional array. You will also see towers grouped together (not AM's), and these are sometimes called "tower farms". Usually there are a couple big airports in the area that tend to preclude placing towers all over town. So that fact, (and usually local zoning and land use restrictions) tend to group all tall towers together in the same section of town. It may also be that someone figured out a long time ago that that was the best spot to put a tower to cover the market, and everyone followed suit. That's how a lot of "tower farms" got started in the first place! Hope this helps to answer some of your questions.


For most other towers, the tower is merely the structure that holds the antennas. A given tower might hold dozens of antennas, from cellular, to paging, two-way, even television & FM's.