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Tricks and Treats of the Trade

I wondered if the fine would have been levied had the owner driven to the hardware store, bought a board and screwed it in place while the inspector was on site.

(click thumbnail)Figure 1: A useful engineering ‘tool’I wondered if the fine would have been levied had the owner driven to the hardware store, bought a board and screwed it in place while the inspector was on site.

It’s the tower manager’s business to load it with leased antennas. It must be understood from the beginning that the AM or FM signals will be protected.

Can you identify the item in Figure 1?

You can tell from the cobwebs it’s not used very often. I’ll give you one more hint: the photo was taken inside a tower fence.

Read on for the answer.

. . .

At a recent state conference, one attendee candidly spoke of his recent forfeitures for violating FCC rules. His incident stemmed from a wooden fence slat that was missing from the rear of the AM tower fence.

Because it pointed away from the building, no one really noticed it. But the inspector did, and the citation cost the station several thousand dollars.

I wonder if the fine would have been levied had the owner driven to the hardware store, bought a board and screwed it in place while the inspector was on site.

The second fine was for incorrect base impedance. Seems several antenna leases were written for this tower and the base impedance shifted with each new antenna mounted. The result was a severe over-power condition that no one knew about.

The jocks continued to write down the “licensed” base current, which was figured using the base impedance before the leased antennas were installed.

This is just another area to watch for, and another reason to involve the engineer in any decision to lease tower space.

In an unrelated case, I was visiting a customer who was complaining of an increase in VSWR and coverage loss for his FM. Of course it was easy to blame the problem on the antenna or the transmitter. One look at the new leased antenna column mounted below the FM antenna – protruding up through the bays– and the cause of the problem was apparent.

Had the owner discussed the new lease with his engineer? No. Had the owner discussed the location of the new antenna with his engineer? No, again.

The owner saw a big check every month and didn’t look beyond the money. I pondered whether that monthly check would have offset the fine for the unlicensed “directional” FM antenna, caused by the new lease arrangement. Fortunately, the leased antenna was remounted lower on the tower and the problem was corrected.

This same problem can occur when a radio station sells his tower to a consolidator or tower management company. For the most part, these tower management companies do a good job. But placing leased antennas within the aperture or to the sides of the FM bays invites trouble.

Remember, it’s the tower management company’s business to load that tower with leased antennas. It must be understood from the beginning that the AM or FM signals will be protected. This not only protects your listeners and revenue stream but it can prevent a costly fine.

. . .

I had the good fortune to talk with Joe Husnay when he spoke at the Virginia News Network Affiliates Conference. He is a resident agent of the FCC Enforcement Bureau in Chesapeake, Va.

He mentioned an interesting site for every broadcast engineer to peruse. It’s the FCC’s Public Notice of Enforcement Bureau Field Operations List of Actions Taken. It’s a mouthful, but it’s an interesting monthly news release compiled by the commission.

Found on the Web at, this monthly summary describes the notices of apparent liability, notices of violation and citations issued nationwide.

The June summary included three pages of EAS-related violations and six pages of tower-related violations. One thing that lessens the blow is that many of the tower violations were for non-radio broadcasting companies, such as wireless companies. It’s nice to see that the radio broadcaster isn’t being singled out for inspections. The rules apply to every licensee.

The FCC inspection checklist is at this site. It’s the same one the agents use when they inspect your station. Print out a copy and perform a self-test. Better yet, find out if your state association provides an alternative inspection program. These programs use contract or consulting engineers to perform a thorough inspection of the station.

When you comply with the areas inspected, the station receives a certificate of compliance, and so does the FCC enforcement bureau.

Unless there is a specific complaint about the station, the certificate will postpone an FCC inspection for three years. Considering the alternative of forfeiture, the cost is a real bargain.

. . .

The Burk ARC-16 is a good workhorse remote control system, writes Bob Hawkins, CE at WENS(FM) and WNOU(FM) in Indianapolis, Ind.

One thing that has irritated Hawkins, though, is how quick on the trigger the call-out alarm system is. I agree that not many of us want to be awakened at 2 a.m. to find out that there was a 50-millisecond power interruption at the transmitter site.

This same call-out eagerness makes the call-out alarm unusable for AM stations where a pattern change occurs!

Hawkins has talked with Burk but said they have not offered a solution. The good news is that he found an answer with Radio Shack.

Attaching a large electrolytic capacitor across the metering input will keep the metered signal from dropping for a few seconds. This is long enough to keep the call-out from being activated but still allowing faults longer than a few seconds to alert you.

The value of the capacitor will vary depending on the impedance of the metering sample, but Hawkins suggests arming yourself with a few values between 470uf and 4700uf. Any voltage rating of 12 volts or above will be adequate.

There’s even a side benefit to this “mod.” The meter readings will show more stability. Minor fluctuations will be ironed out, making the parameter easier to log.

Imagine never hearing another operator telling you that the output power is jumping from 100.1 to 100.4 percent and wondering which one to log! A big thank you to the “Shack.”

(click thumbnail)Figure 2 : Ray Fantini places the hood over the tower photocell light
(Ed. Note: RW also touched base with Burk about this question. General Manager Anita Russell replied, “We are responsive to customers’ comments and have a solution for this problem in Engineering. All of our current users will be notified when it is available.”)

. . .

Well, have you given up on guessing the use of that engineering “tool” we described in Figure 1?

Figure 2 shows Ray Fantini placing the hood over the photocell for the tower light, to check operation. The cardboard hood beats covering the photocell with a rag or electrical tape and is much simpler to remove.

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