Think like your insurance guy.

Start with what’s most likely going to take you off the air. Flooding? Locate your main studios on the second or third floor. Tornado? Move it to the basement. Flooding and tornado? Have a studio on each floor. Every little bit of precaution helps. We know of a few broadcasters in Florida who are using optical fiber throughout instead of copper cabling as one more safeguard against a lightning hit, for example.

Use separate circuit breakers.

True story: one of our larger network installations involved an elaborate web of interconnected edge switches segmented to dual redundant core switches to isolate studios. Only problem was, those core switches were racked up a mere two feet from each other … on the same circuit breaker. Luckily, an astute Wheatstone field engineer caught the error before it became a problem. Make sure you’re setting up islands of reliability all the way to the circuit breaker.

Create a remote access path.

Do you have a secure path to remotely access the studio in an emergency? If not, you should. A separate line into the studios (you can get DSL connectivity for $50/month) could very well be your only lifeline to the outside world in an emergency, and it could provide outside access to the studios in order to manage a disastrous situation.

Empower your network.

Make sure your audio network knows what to do in an emergency. It should be able to detect silence in the program chain and know which studio or source to switch over to the instant it happens. In the case of WheatNet-IP audio networks, this can be established easily using our software. The hardware I/O units are already self-empowered; if a disaster should take out an I/O BLADE or group of BLADEs, the other BLADEs in the network will automatically reconfigure to continue operating as usual.

Talk to your network …

so you can detect issues before they become a problem. Your audio network should have admin tools for this purpose. One of the more powerful advantages of the WheatNet-IP audio network is being able to monitor each I/O connection point in the network using SNMP-based management software. This is useful for alerting if a particular port is dropping packets or if a device is heating up and about to fail. Each WheatNet-IP BLADE has a unique Management Information Base (MIB) with hundreds of data points for tracking bitrates, temperatures, etc.

Backup. Backup. Backup.

Our field engineers suggest you back up your crosspoints on a regular basis and put this data on a thumb drive or on a server that is backed up on a cloud somewhere. In fact, we recently added a crosspoint backup feature to our system software for this purpose. And while we’re on the subject of backups, always keep a working backup generator at the studio and a backup audio recording at the transmitter site so that if you should lose connection between the studio and transmitter site, you haven’t left your listeners in the lurch. We now offer an optional built-in audio clip player for our BLADE-3s that can be used to put emergency audio on the air. The player can be triggered manually or automatically following a period of silence detected by the BLADE-3.

Have an exit plan.

But take your listeners with you! If you have a WheatNet-IP audio network, it’s almost as easy as grabbing an I/O BLADE off the rack and connecting it to a live microphone. You might not always be able to find an Internet or hot spot connection, but in a lot of cases you will. As extra insurance you can also keep an EDGE unit on hand along with an unlicensed-frequency IP wireless radio system to give you line-of-sight connectivity to the transmitter should you need it. That could make all the difference if you’re the only one on the air talking your listeners through that big tornado or hurricane or other contingency.

A spiral stairway leads downstairs to a room now largely relegated to storage. A fully functional machine shop still resides here, with a lathe and band saw and milling machine; the site was designed to be self-sufficient and to even fabricate replacement parts for its own equipment. Station engineers still use these tools; once, a gear in a mechanical aircraft beacon on the roof broke. Engineers simply made a new gear themselves. Outside the double doors of the downstairs shop, huge propane and diesel fuel tanks and emergency generators stand ready to keep the whole site running without outside power. An emergency underground shelter beneath the front of the building still stands ready.

During wartime “Everybody knew we had the Army on the roof,” says retired Chief Engineer Watt Hairston, himself a legend. “But few people know we had the Navy in the basement.” The project, involving use of the mighty tower for emergency backup signalling to submarines, was once highly secret. It’s now been declassified, so it can be revealed that a huge transmitter resided here, and the Navy was fully prepared to commandeer the tower had either of its main VLF communications facilities been lost to enemy action.

Able to wait no longer, I walk outside and begin the trek across the field to the tower itself. The massive diamond-shaped “dual cantilever” design was built by Blaw-Knox and was originally 878 feet tall. Found to be too electrically tall, causing a skywave convergence zone, it was shortened by 70 feet in 1939 to its current 808-foot height. This radically improved its coverage, and even today with modern analytical and modeling techniques, the tower has been shown to be at its optimal height! That's a pretty impressive feat for some guys with slide rules and logarithm tables.

Over my head is a fascinating feed line system, no longer used but still quite intact. It’s an open-wire coaxial feedline. Hairston remembers birds damaging the insulators, and after many harrowing repair experiences, he elected to install a conventional underground coaxial feed, which remains in use today. The original feed to the tuning house was an 800-ohm balanced overhead line; the insulators and pass-throughs for this line can still be seen today on both the transmitter building and tuning house.

I’m met at the tower base by the station’s assistant chief engineer, a personable young man named Joey. As guests peer through the door at the huge ceramic base insulator, he casually explains its purpose to the uninitiated. The set of two mammoth Lapp insulators, stacked ball to ball with a pin between them, electrically isolates the tower from the ground, and supports the full weight of the tower as well as the downward component of the guy wire tension. The total weight is estimated at around 300 tons. Incredibly, the insulator system is rated to hold twice that weight. The original insulators have been in place since the tower was constructed in 1932.

A thick, sturdy brick wall surrounds the insulators to a height of around 9 feet, with a steel door that opens toward the brick tuning house a few feet away. The wall is designed to protect the insulator against flying debris in the event of a storm, bullets from vandals with rifles, and shrapnel in the event of a bomb’s near miss in wartime. The inside of the wall is covered with a thick metal screen, which Joey indicated was meant to catch brick shrapnel in case something impacted the outside of the wall. You may imagine that when a piece of ceramic is under that much compression, it wouldn’t take a lot of the wrong kind of impact to fracture it.



Seeing the tower from its base is at once intimidating and fascinating. When you stand at the base, you’re not standing beside the tower. Because of its design, you’re actually standing under the middle section. Gazing up at the structure from this angle, the upper half of the tower seems to disappear completely, and all one sees is an inverted pyramid with guy wires attached to its wide top. It’s quite a dizzying sight!

On the way back to the transmitter building, I meet Chief Engineer Jason Cooper, and we spend a few minutes chatting about the tower’s history. “Over-engineered and over-built,” is how he describes the structure, saying that it’s needed only very minor repairs over the years. He and Joey have a major task keeping this site well maintained and operational. Redundancy is a key word here. In addition to the two 50,000 watt transmitters and the big tower, WSM maintains an auxiliary tower (a shorter, relatively pedestrian uniform cross-section guyed tower to the west of the main one) and a 5,000 watt emergency transmitter to drive it. Just in case.

Jason tells me that atop the tower, now disconnected, remains an FM turnstile antenna. But this is no ordinary FM antenna — it’s designed for the older, low-band VHF channels of the original Armstrong FM system. In 1941, WSM-FM (originally W47NV) was the first commercial station in the US to receive an FM broadcast license from the FCC. If one looks closely at the top of the tower, the antenna can still be clearly seen. That’s quite a piece of history!

After spending a relaxing hour or so talking with other guests and listening to Bill Cody interview country music greats and Grand Ole Opry stars old and new, I thanked my hosts for their hospitality and reluctantly drove away from the iconic site where for 90 years, the radio signal carrying the Grand Ole Opry had been transmitted, casting a last look over my shoulder at the iconic red-and-white spire, the symbol of radio broadcasting at its very finest. I can almost hear the father of bluegrass, Bill Monroe, singing, “Y’all come and see us when you can.”

Scott Johnson is a systems engineer, webmaster, and video producer with Wheatstone Corporation.

{gallery}GibralterWebImages{/gallery}