Weekly Tech Reminders: UPS, Tower Lights and LUFS

An excerpt from this week’s Monday Morning Coffee and Technical Notes
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The following is excerpted from the Alabama Broadcasters Association's weekly e-newsletter, Monday Morning Coffee and Technical Notes. Thanks to Larry Wilkins, who puts together the content and has shared it with Radio magazine readers. To subscribe to the newsletter, send an email to lwilkins@al-ba.com, and he will add you to the database.


One thing engineers and managers know for certain is the importance of redundancy. The loss of audio or video can often bring on a panic attack. Having reliable back-up equipment is important. The same goes for power. Uninterruptible Power Supply units have been around for a good while. Engineers should take time to plan out their needs for UPS in the broadcast plant. There are a lot of decisions that must be made to create a functional backup power system.

A good starting point when planning is to look at the strategic part that Standby Power plays. The uncertain quality of power drawn from the National Grid involves far more than power cuts. Momentary power interruptions, electrical current surges and dips in power all create problems for sensitive electrical equipment.

Therefore, having a Standby Power strategy, and understanding the full implications of that strategy, and how it will impact on the ongoing success of your business, is paramount.

Here is a great resource for planning your back-up power system.


Although all engineers should already be aware of the rules covering tower lights, we thought a quick reminder would be in order.

Part 17 of the FCC Rules requires the following:

The owner of any antenna structure which is registered with the Commission and has been assigned lighting specifications, shall make an observation of the antenna structure's lights at least once each 24 hours either visually or by observing an automatic properly maintained indicator designed to register any failure of such lights, to insure that all such lights are functioning properly as required; or alternatively, shall provide and properly maintain an automatic alarm system designed to detect any failure of such lights and to provide indication of such failure to the owner.

In addition, owner shall inspect at intervals not to exceed 3 months all automatic or mechanical control devices, indicators, and alarm systems associated with the antenna structure lighting to insure that such apparatus is functioning properly.

The exception to this rule is for any antenna structure monitored by a system that the Wireless Telecommunications Bureau has determined includes self-diagnostic features sufficient to render quarterly inspections unnecessary, upon certification of use of such system to the Bureau.

Owner is also required to report immediately to the FAA, by means acceptable to the FAA, any observed or otherwise known extinguishment or improper functioning of any top steady burning light or any flashing obstruction light, regardless of its position on the antenna structure, not corrected within 30 minutes and must maintain a record of any observed or otherwise known extinguishment or improper functioning of a structure light. This record shall be retained for a period of two years and provided to the FCC or its agents upon request.

Download a copy of the FAA’s tower light report here.


Having problems trying keep all your audio files the same “loudness?” Normalization just doesn't do the job.

Craig Anderson writing in Sweetwaters' Insync said, “This has resulted in a lot of collateral damage — like distortion, listener fatigue, and no dynamic range.”

He said, “Basically, we now have loudness meters whose capabilities extend conventional VU, or peak, meters and are based on a spec called Loudness Units. LUFS stands for Loudness Unit Full Scale, which references Loudness Units to full scale.”

Craig continued, "in a nutshell, loudness units are the unit of measurement used in the process of quantifying a [audio file] perceived loudness by analyzing the average level over time. In theory, two [files] that register identical LUFS readings should sound like they're at the same level, and in practice, they do indeed sound like they're at the same level, regardless of whatever the peak or RMS readings say".

Read Craig Anderson's great article at Sweetwaters Insync.