Old AM Broadcast Towers Get a New Life

Esther Schindler shares an article from Hewlett Packard Enterprise: Video may have killed the radio star, but other media certainly make old AM radio towers superfluous... maybe. "As once-loyal listeners tune away, most AM stations are barely holding onto life, slashing staff and budgets as deeply as they can while struggling to find a return to profitability," reports HPE. "Once upon a time, having a broadcast license of any kind was like having a permit to print money. In today's world, that's no longer true." But, with some 10,000 AM broadcast towers in the United States stretching high into the sky, there may be an opportunity for wireless carriers who don't want to argue with community opposition from neighborhoods where residents don't want yet another cell tower. The amount of money an AM station owner can pocket by sharing its tower with a wireless partner varies widely, depending on the tower's location, height, and several other factors. But it's certainly more income -- and a way to keep "old" technology from becoming obsolete. "Using an AM tower, which has very often been in place for many years, avoids many zoning and other permitting issues, versus going in and creating a new site for a tower," Behr explains. He says local residents, businesses, and officials rarely complain about an AM broadcast tower that suddenly begins serving as a cell site. "That tower was there before they were, and it doesn't bother them," Lawrence Behr, CEO of Greenville, North Carolina-based LBA Group, says. "Hanging a few things on it is rarely controversial, so that's a real good thing for AMs."

Comments

Radiation

[dwywit]

Honest question - isn't it necessary to de-energise the transmitter before technicians can climb the tower to install or maintain hardware? Presumably it happens in the graveyard shift. The ERP right at the tower must be quite high.

Re:Radiation

[Known Nutter]

You can be on the tower, or you can be on the ground, but you can't be on both. It's not the potential that kills, it's becoming a circuit path. Birds roosting on power distribution lines, which as a general rule are not insulated, don't die due to that fact.

That's not how any of this works.

First, the tower is grounded and at the same potential as earth. The primary concern is not electric shock.

The parent poster was concerned with worker safety when exposed to radio frequency energy.

https://transition.fcc.gov/Bur...

After performing the required calculations and determining it is safe to work at x distance from the transmitter antenna, workers will typically wear a personal RF monitor to measure exposure.

Re:Radiation

[DRJlaw]

That's not how any of this works.

First, the tower is grounded and at the same potential as earth. The primary concern is not electric shock.

Please, tell me how AM broadcasting works (first and last visible paragraphs of section 5.5.5.2). Because for the majority of AM transmission towers you are dead wrong - literallty.

"Most AM radio towers are series fed (end fed at the bottom) and have a ceramic insulator at the base. A few smaller ones are shunt fed about 20 feet up the tower and are grounded at the base, and a variation are metal poles grounded and have wires insulated from the pole as vertical radiators."

Up to 50,000 watts says that the primary concern is electric shock. A secondary concern is RF exposure.

Try Googling AM radio, maintenance, and "hot tower" before you lecture about areas that you plainly lack experience in.

We need to keep ALL of that old infrastructure.

[jenningsthecat]

The AM broadcast-band, (and its close relatives, the short wave bands), allow for long-distance radio communications. Even in the daytime the coverage is pretty good; but at night, when the ionosphere allows for 'running skip', its reach is truly impressive. There may be times in the future when that's crucial for reaching people over very large geographical areas. We really need to backstop our wired networks with wireless analog broadcast capability. It can reach anybody who has a $5 pocket radio, it continues to work even when all you have is batteries or generators and a tower, and it doesn't rely on hard links that can easily be broken. And it's already there, fer chrissake - all we have to do is maintain it.

AM towers are RF hot, folks

[swschrad]

unlike TV and FM towers, the AM tower > IS the antenna. the tower is hot. they are isolated by placing them atop large ceramic insulators. if the station is still on the air, this poses gigantic grounding and potential RF coupling into a cell service.