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The author is owner of Rural Florida Communications Cooperative. He is a retired AT&T employee who has a great deal of experience protecting communications facilities from lightning and surges. He saw Mark Persons’ recent account in Radio World of a lightning strike to the pole supporting the KRJM STL antenna and was inspired, first, to provide some tips for John Bisset’s Workbench column in the Dec. 9 issue, then offer the following in-depth article for readers of RW Engineering Extra. We in turn are inspired to share it with you.

A wise man who invented the air terminal, Benjamin Franklin, once stated, “An ounce of prevention is worth a pound of cure,” and the lightning damage at KRJM bears witness to that.

Now, let me start with dispelling an old myth. I have heard from a number of engineers that “If you take a direct hit, it’s all over; there is nothing you can do to prevent that.”

Such a statement is patently false. The Tier 1 Carrier I retired from has tens of thousands of cell sites and switching offices all over the U.S., and they take thousands of direct hits annually without sustaining any damage at all.

Why? Because we engineer layered lightning protection into each site. Be it standalone, collocated on a broadcast tower or on a rooftop, proper protection equals greatly lowered losses and greatly increased uptime.

So how is this done? Well, let’s use the example of KRJM(FM), which Mark Persons wrote about in “What Happens When Lightning Hits? A Case Study,” which appeared in Radio World in October, and which you can find at radioworld.com by searching for keyword KRJM.

Beginning with the improperly protected and grounded pole and ending at the last burned-out device, this is a perfect example of where an ounce of prevention could have prevented a lot of heartburn.

Let’s start with the pole. When I see a pole shelled out from lightning, the first thing I look for is a down conductor. I could be incorrect, but I don’t see one on that pole.

Fig. 1: A properly installed pole with down lead. (Click here to enlarge.)

A down conductor is a simple lightning protection device. Before the pole is placed, an AWG #6 hard-drawn copper conductor is placed on it using fencing staples, attaching it from the top of the pole to the butt. The installer leaves six or so inches of the conductor standing above the top of the pole and coils up a few feet of it on the butt, starting in the center, and where the conductor crosses over itself, places a staple diagonally to connect the two conductors to each other.

The goal is to produce a low-resistance, low-impedance grounding electrode on the butt of the pole. When the pole is placed in the mounting hole, it will make good contact with the earth, producing a good solid grounding electrode.

The down conductor provides a bypass for the lightning energy to earth, sparing the pole and any attachments from damage. See Fig. 1.

If the pole is already placed, a down conductor can be added by placing a ground rod with a minimum length of eight feet into the earth.

One important note: Always call for a utility locate before driving a ground rod or doing any digging. In most states, the number is 811. Failure to do so can get you killed, or if you survive hitting a buried utility line, the least you’ll get is a substantial bill from the utility for the underground damage you caused.

The installer then installs the down conductor in the same manner as a new pole, minus the below-grade work, connecting the down conductor to the grounding electrode.

All that protects the pole, but what about attachments?

The first step is to bond all attachments to the down ground lead with an AWG #6 copper conductor. That’s your first layer of protection.

The next step is surge protection, commonly referred to as Transient Voltage Surge Suppression.

A TVSS can be installed in one of two locations. The best location is where the cables coming off the tower or pole enter the building. However, if the building is metal, it is better to deploy a primary TVSS near the base of the pole or tower.

If the TVSS is rated for outdoor installation, a cabinet is not required. However, most of the time you will want to keep the TVSS in a dry location and out of sight.

Fig. 2: TVSS devices installed on a ground bar. (Click here to enlarge.)

Either way, the TVSS should be installed on a common insulated buss bar. This bar should be bonded to the pole or tower ground and grounded to the main grounding bar (MGB) in the building. The minimum recommended grounding conductor is AWG #4 copper, unless the distance between the pole ground bar and the MGB exceeds eight feet. Then it should be stepped up to an AWG #2 copper conductor. See Fig. 2.

Bringing It Inside

The common method when bringing cables into a studio or transmitter building is to use a bulkhead. This can be as simple as a sheet of nonflammable water-resistant material such as Hardie Panel sheeting or acrylic plastic.

In a metal building, this is mandatory. You do not want to penetrate a metal building where a cable can be in direct contact with the metal wall. That is begging for arc-over problems.

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The point where the cables enter the building is where you will place your primary or secondary TVSSes. The MGB should be placed as close as practical to this penetration, but no more than a couple of feet away.

Each TVSS should be connected to the MGB with its own grounding conductor. Never double up grounding conductors. The grounding conductors should be placed either right or left of the center of the MGB. The conductors should be swept in from above and not reversed below and upward where they connect to the MGB. The primary grounding conductor for the MGB should be connected at the center of the MGB.

The reason for connecting the main grounding conductor to the center of the MGB is to isolate incoming conductors that introduce surges on a regular basis (dirty) from the sensitive equipment (clean), which must also be connected to the MGB to be protected.

Fig. 3: This installation follows the PANI order, with surge Producers, Absorbers, Non-isolated and Isolated from the center main grounding bar out. (Click here to enlarge.)

The center MGB ground serves to provide this grounding isolation or PANI, an acronym describing a way of bonding conductors to the MGB in a specific order, depending on their origin: surge energy Producers, Absorbers, Non-isolated equipment and Isolated equipment (Fig. 3).

Power and Utilities

More commonly than not, the power, telco and CATV are not going to enter the building at the same location as the cabling off of the tower or pole, but they must also be protected, so let’s start with power.

Fig. 4: The watt-hour meter is a good place for additional TVSS protection. (Click here to enlarge.)

Your building will have a watt-hour meter, and it’s usually installed outside (Fig. 4). Even if it is a “smart meter,” it’s a simple device that allows your electric utility to vacuum funds out of your bank account and transfer them into the utilities bank account. However, that watt-hour meter can be used to your advantage.

There are devices known as meter-based TVSSes, which are sleeves that are installed by either a licensed electrician or the utility between the meter base and the meter. Some utilities will allow your electrician to do the work; others insist that you rent the TVSS from them for a small monthly fee. Either way, they are good protection for the cost. They are crude first-line devices that can take the brunt of a hit.

But don’t stop there. Always have a hard-wired TVSS installed as close as possible to the service entrance. Some will require a circuit breaker to be installed ahead of the TVSS to prevent a catastrophic burn-down of the TVSS should it go into a total failure after doing its job.

Fig. 5: Don’t skimp when buying TVSS devices! Get the best you can find. (Click here to enlarge.)

That breaker should be installed as close as possible to the main breaker in the service panel. If that requires moving breakers around to clear a double space, so be it. If the service panel is choked up with no spare spaces, drop in a sub-panel and unload other circuits to the sub-panel to make space for the TVSS breaker.

Do yourself a favor and don’t go cheap. Real TVSSes for power run anywhere from $400 to $2,500+, depending on the rating of your service entrance and if it is single phase or multiphase power (Fig. 5).

On the Inside

If you have a load center within your building, this is a great place to add a secondary panel buss TVSS. While not breaking the bank, most manufacturers of load centers offer TVSSes that simply slot in like a multipole breaker. Like a primary TVSS, they should be installed next to the feed to the panel. If needed, have your electrician relocate one or two breakers to clear up slots and you are good to go. See Fig. 6.

Moving down in voltage, we have telco, cable and CATV. These incoming services need to be protected as well.

Fig. 6: Panel-mounted TVSS devices are a great additional line of protection. (Click here to enlarge.)

Normally your telco provider will provide a network interface device (NID). Within it will be protectors, commonly gas-based protectors with a 400 VDC breakdown. As long as the NID is properly grounded and bonded to the building’s ground system, that provides good primary protection. Internally, you want to back that up with TVSSes rated for no more than 200 VDC for POTS phone lines. Special circuits, however, are a horse of a different color. Digital or audio circuits behind the telco’s mounting need to be protected by very low-voltage TVSSes, 50 VDC or less.

Commonly, cable and CATV will utilize a spark-gap protector, and like telco, it must be grounded and bonded to the building’s grounding system. However, a spark-gap protector is unsuitable in this application. Back it up with a reputable coaxial TVSS mounted to the dirty side of the MGB ahead of the distribution of the cable or CATV signal within the building.

Grounding and Bonding

Now, for a somewhat more complicated subject, grounding and bonding. It is extremely important that all connections to earth be bonded to each other. Lacking that bonding, surges entering your facility over various services connected to disparate earth connections will wreak havoc within your facility.

Grounding & Bonding Tips

• Always bond devices, racks, attachments, etc., swept toward the main grounding bar.
• Wire-brush paint from both sides of equipment mounting tabs where grounding connectors will be placed and the rack faces they will be mounted to, exposing bare metal.
• Most modern racks and rack-mounted equipment are aluminum-framed, therefore always use bimetallic connectors when bonding such equipment to copper grounding conductors.
• Always apply a thin coat of antioxidant such as NO-OX to the bare metal before assembly to ensure a long-lasting corrosion free connection.
• Always use compression connections and the proper crimping tools and dies or use exothermic welds. If a connection must be soldered, silver solder is required. No exceptions.
• Always tag the grounding connections at the MGB and subsystem ground bars. You may be the next person who has to work on the system, long after it was built, and memory may not serve to remind you what all these are.

An example would be if your facility was not built from the ground up as a broadcast facility. While the structure is wired to code, you later add something simple such as a DTV or other satellite dish.

That dish must have a clear view of the southern sky, but your electrical service and other utilities may enter a different side of the building, say the north side. Not a problem.

The contractor for the DTV provider or the dish installer installs the dish on the south side of the building’s roof, then runs the coax from the dish down and through a spark-gap protector, which is earthed to a ground rod he placed. That ground rod, however, is commonly not bonded to the building’s grounding system by the contractor.

Later, during a storm, lightning tickles that dish. The resulting energy saturates the unbonded ground rod and the remaining energy seeks out all other forms of an earth ground it can find. In the process, it passes through the connected receiver and then enters the building’s electrical system. From there it passes through and into any source of a ground to earth. This would include neutral, any electronic device with a three-wire cord, or grounded rack-mounted equipment. Sometimes lightning energy will find a ground just by arcing within the building’s wiring system and devices, destroying them in the process.

The solution to preventing such damage is to bond all connections to earth to each other with a minimum of an AWG #4 direct-buried copper conductor. This provides a low-resistance path from all grounding connections to earth, eliminating any differences in voltage potential between those connections.

Yes, all those connections may become saturated for a moment, and yes, there may be substantial rise in potential on all of them, but the bonds prevent any flow of energy through the protected equipment within the structure.

Comment on this or any article, email rweetech@gmail.com.

 

The post TVSS for Broadcast Facilities appeared first on Radio World.

Roberto Tejero is senior product manager for AEQ. This interview is excerpted from the ebook “Console Tech 2021.”

Radio World: What is an aspect of your product that highlights how consoles and surfaces for radio broadcasting are changing?

AEQ: The great flexibility in the relation between the core or mixing engine and the control surfaces. 

For instance one Atrium XCore Mixing engine or frame can distribute the control of its inputs and outputs for up to six different mixer control surfaces — six mixers/studios in one. This rationalizes the installation and makes it incredibly cost-effective. Both installation and workflows become very flexible. 

Likewise, dual mode operation is interesting. In a studio we can control the console from several different modules with the same or different functionalities.

RW: What makes that notable?

AEQ: An example would be the configuration of Studio1 at station IB3 at Palma de Mallorca, Spain. 

In addition to the presenter/audio technician or operator of the console, there’s a producer in charge of call screening and coordination of complex programs. 

The producer needs to carry out certain operations independently but in parallel with the technician and others, such as technical intercom. 

Thus, this console has been set up with two control modules. The first is used by the technician or presenter in a traditional way. The second has been configured for the producer to handle certain functions in parallel with the technician, such as adjusting levels of the inputs and outputs for the phone-in or talk-show system at the same time as he or she coordinates the show with the system intercom functions.

RW: What features are available that may not have been a few years ago?

AEQ: There are several, and not only applicable to the Atrium console but to all AEQ Digital consoles. 

For example, at night, when most of the programming is automated or relay transmission of networked or syndicated programming, and when controls and studios typically are unmanned, AEQ consoles can be remote controlled. 

Such control can be accomplished from the station’s central control or even from a remote location or by a technician “from home.” The applications allows for the full control of the Atrium, i.e. all features and functions from simple channel on/off and level adjust to complex EQ. settings and N-1 or mix-minus operations, remote connections or relayed program bypass. Atrium when equipped with motorized faders will also follow these settings in remote control.

Other great features: AoIP connectivity allows for the inputs and outputs, elements for process and control to be distributed throughout various equipment that can also be distant physically. 

Also, remote control of various devices can be transported through the network and integrated through programmable keys of the console. Playout automation, codecs and other equipment, or camera and source switching for visual radio applications, can be an integral part of your console.

And information pertaining to the system’s different audio levels can be available throughout the control network to allow for monitoring through virtual VU meters and Visual Radio applications where video follows audio.

AEQ Atrium AoIP Mixing Console

RW: After years of discussion about interoperability, are surfaces still “locked” to a specific AoIP network or are are they interoperable?           

AEQ: The AES67 standard allows for IP Audio multi-channel interoperability but does not contemplate the control. Therefore, the most sensible thing in our opinion is to set the system on a default AoIP format and then facilitate access to other, different protocols. 

At AEQ we adopted Audinate’s Dante protocol as our native format, but given the type of equipment we design and produce, we wanted to render our gear the possibility to interconnect audio in all types of formats:

-Through one or more XC24 cards we connect in DANTE to our own devices and also to any third-party manufacturer that are using Dante as their protocol. Device and channel discovery is instant and automatic and makes the installation very, very easy and convenient.

-If we have to work with non-Dante equipment, we install additional cards in the engine. With an XC24 card, configured in AES67 mode, we can exchange up to 64 audio channels in AES67, for example with Livewire+ or WheatNet equipment. If we add a device to the network with the Dante Domain Manager application, we can also exchange audio with IP video devices in SMPTE ST 2110 -30 format.

If we add an XC34 card, we can exchange up to 128 audio channels in AES67 or Ravenna, for example with Lawo equipment. With these cards, we can also exchange audio with IP video equipment in SMPTE ST 2110 -30 and SMPTE ST 2110-31 format with control through the NMOS protocol.

And of course, also the varied types of non-IP audio: From SDI Video embedded audio to multi-channel MADI/AES10, digital stereo AES3 (AES/EBU), analog, microphone, headphone outputs, etc.

RW: Is there a “design philosophy” taken by your developers? 

AEQ: Broadcast equipment is developed for users who are working long hours and sometimes exposed to great stress. It is essential that the user is comfortable, that he or she can work quickly and precisely.

For example, take the screen for Atrium’s single-channel, four-band parametric EQ (shown). 

Atrium’s single-channel, four-band parametric EQ.

The curve can be adjusted by simply dragging the graph from one of the four snap points. But for more precision, below the graphic are each band’s three adjustable parameters: frequency, Q and gain. These can be modified moving the corresponding cursors horizontally.

But if your fingers are not accurate enough to set the required parameters, you can click on any of these and it will highlight in yellow. Now this parameter can be precisely adjusted using a TOUCH & TURN encoder on the main console.

The post Flexibility & Control Define Today’s Surfaces appeared first on Radio World.

The community ERI FM antenna on Mt. Morrison, overlooking Denver. Note the substantial excavation of surface rock and the lack of topsoil.

The author is a Denver-based engineer and lover of a good thunderstorm.

The Rocky Mountains are young as mountain ranges go. Colorado has 53 “fourteeners” … mountains over 14,000 feet above sea level. The mountains of the Front Range in the Denver radio market are only 7, 000 feet above sea level, but they are made from solid sandstone, limestone and granite rock.

These mountains are great for transmission sites — high altitude radio and television stations cover the market well. The area sees some extreme spring and summer thunderstorms as cold northern storm fronts meets warm, humid, southern air. Lightning strikes, both direct and remote, interact with the above-ground utility power lines that feed the sites. These natural events create issues ranging from minor AC line voltage transients to serious equipment damage.

Lightning

Lightning occurs when naturally occurring electrostatic charge builds up to a flashover voltage, ionizing the surrounding air. A great surge of electrical energy is released almost instantly to a point of low-voltage potential. Earth ground has a low-voltage potential because the free charged particles, also known as ions, are plentiful in the soil.

In the Rocky Mountains and other mountainous areas, the ground situation is different. Some mountains are solid or fractured rock which have little or no deep soil on the surface to “ground” the lightning strike. Radio, television and communications sites situated on rock summits need a sufficient RF ground. Remote lightning strikes several miles away can also, through inductance, enter power lines. A small power bump or a bit of electrical noise can lockup digital equipment.

Ground Systems

Where soil is plentiful, several copper rods driven into topsoil can provide an adequate electrical safety ground that meets NEMA electrical code. But what if there is little or no soil on the surface, such as on a rocky mountaintop? The median resistivity of topsoil is approximately 26 ohm-meters compared to the median resistance of solid rock that range from 1,000 to 5,000 ohm-meters. Low-resistivity soils typically contain more salt and moisture than high-resistivity soils.

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Symptoms of an inadequate RF ground system include transmitter and transmission line damage, equipment lockups and frequent circuit breaker trips. Communication sites built on solid or fractured rock may need a more substantial ground system; this can be done by adding chemical augmentation. Augmentation systems generally are made from copper tubing drilled with leach holes, and are filled with water and a salt such as magnesium sulphate. The brine solution leaks into the surrounding rock and improves ground conductivity with a greater supply of free ions.

Taming Lightning

When lightning strikes a tower, the energy enters the transmitter building, and then tears through the transmitter because the path of least impedance is located through the utility power ground in the transmitter. A properly designed and constructed RF ground system can reduce the probability of lightning damage. Electrical power systems typically use copper cable for grounding, but RF sites often use flat, copper strap which has a lower impedance at radio frequencies.

Both electrical power and radio transmission lines should enter the building at the same point (bulkhead) with transmission lines being bonded to the RF ground node with short, low-impedance conductors. This is also a good location to place the RF ground buss bar and cable ground kits. Electrical power panels should be located near the RF ground node with both ground and neutral busses bonded to the RF ground node. All RF grounding connections should go “one way” with no reconnection to the RF ground node and no ground loop.

Nautel has published a white paper entitled “Lightning Protection for Radio Transmitter Stations” that goes into more detail on this type of ground system.

One way to reduce lightning propagation to the transmitter is with ferrite cores slipped over the transmission line prior to connection to equipment. Although RF cables are grounded, there is still a low impedance in the outer conductor. Energy from a lightning strike to the antenna or transmission line may substantially bleed off before the line enters the building; yet enough energy may still travel on the outer conductor to cause damage. The ferrite core acts as a “choke,” by creating an impedance to the magnetic field created by the electrical current. It stores energy in a magnetic field, and eventually dissipates the energy as heat. Ferrite chokes can also be used on AC power mains.

Maintenance of RF ground systems includes recharging the chemical systems with water and salts. Ferrites should be periodically inspected to makes sure they are intact.

Electrical outlets should be the isolated ground type whereby the ground and neutral conductors stay isolated from the conduit. All conduit connections should be insulated where the metal meets the equipment cabinet. It’s best to home run all ground and neutral wires back to the power panel, daisy-chaining of these conductors can create ground loops.

Safety

Site safety becomes an issue when there is a poor site ground. Towers, buildings and steel appurtenances need to be connected to a good RF ground system, typically through exothermic welded cables. Air terminals (lightning rods) should be used liberally on the towers and buildings to dissipate atmospheric static charge and create a zone of safety from a strike. Parking lots and walkways should be built over a buried metal grid bonded to the facility ground buss. Metal fences, gates and door jambs should also be grounded.

Lightning strikes can also start wildfires that can threaten transmission sites. Some sites have alternate utility power paths in the event that the primary path is destroyed.

Mountain top sites offer many challenges, but good planning, good design and good construction provide the solution. One more thing … when in doubt, ground it.

RW welcomes your Tech Tips, email us at radioworld@futurenet.com.

The post Rocky Mountain RF Grounding Pointers appeared first on Radio World.

Charlie Gawley is VP Sales APAC/EMEA of Tieline.

This article appeared in Radio World’s “Trends in Codecs and STLs for 2020” ebook.

RW: What’s the biggest trend in this segment of our industry?
Charlie Gawley: Remote control and simple connections are paramount these days. The pandemic has accelerated this demand, but thankfully Tieline was already well-placed to put remote control of all equipment at the engineer’s fingertips.

From a network control perspective, cloud management of all devices is expected. As an example, Tieline’s Cloud Codec Controller lets engineers fully configure and remote control all their codecs remotely from the studio or home. Our Report-IT app can be connected, monitored and allow remote input level adjustment as well. This has been extremely important during the pandemic, as a broadcast engineer can adjust remote audio levels and other settings as required from their own home.

Simple connections are also facilitated by a traversal server like Tieline’s TieLink, which allows creation of call groups, displays codec “presence” and facilitates NAT traversal.

RW: How do you see codec technologies being deployed now in clients’ facilities?
Gawley: Today there are demands to do more with less — essentially looking for that Swiss Army tool in your broadcast kit.

The ViA portable IP mixer/codec has enabled broadcasters to essentially set up a remote operational studio where they can take live calls over SIP, Skype, WhatsApp and mix directly live on-air. Users have been able to do their prerecorded interviews or commercials and either mix them in live on-air or FTP files back to the studio.

Tieline ViA codec

As an example, we have a large national broadcaster in the United Kingdom that has set up a live mixing studio for both radio and TV programs from an engineers’ lounge room due to COVID-19 lockdown restrictions using two ViAs each in triple mono mode. They are connected to four presenters on ViAs in their own homes — all mixed in the lounge room with program audio sent to a Merlin PLUS multichannel codec in Master Control. A producer is connected over Tieline’s Report-IT app to the Merlin PLUS, where a comms channel is fed to the talent off-air.

RW: How about 2020’s “big story,” the sudden explosion in remote and at-home broadcasting?
Gawley: Codecs have played a crucial role in facilitating home broadcasting and keeping stations on-air after the pandemic forced networks to send people home.

For the seasoned Tieline user broadcasting remotely for over two decades, broadcasting from home is just another venue. However, for studio-based talent it would be foreign to them.

There have been two dominant use cases. One involves broadcasters at home using full-featured codecs like the Tieline ViA with record and playback capability and the ability to integrate live callers in a home studio. These codecs also delivered redundant streaming over multiple IP interfaces like cellular and wired interfaces and data aggregation technologies.

The second use case involved rapid deployment to multiple people in an affordable and simple way. Our Report-IT Enterprise app for iOS and Android allowed users to download a software codec and tap “connect” to go live very simply. All the configuration was done remotely by the engineer at the studio or from their home.

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RW: How many ways are there of making connections? 
Gawley: Sales of ISDN and POTS-capable codecs have definitely tapered off, and everyone has either moved or is moving towards IP audio transport.

From an IP perspective, many codecs support unicast peer-to-peer connections or can multi-unicast to dozens of endpoints. Multicasting is also supported to unlimited endpoints over multicast-capable networks. Codec IP audio streams can be delivered over any IP network and integrate seamlessly with all AES67-compatible broadcast studios.

RW: And how powerful do you think codecs can get?
Gawley: Just as processors get more powerful, so do codecs. Today’s leading codecs increasingly include more features and options than ever before. For example, audio processing like EQ, compression and limiting is performed in some. Multiple connections can be configured with multiple redundant streams and data aggregation.

RW: What best practice tips should buyers be aware of in 2020?
Gawley: From an STL and audio distribution perspective, the codecs of today increasingly integrate high-density streaming features, which deliver scalable, space-saving options. It’s what our customers are demanding.

Tieline Multichannel Gateway

For example, our new Gateway multichannel DSP-powered codec delivers 16 codecs in a compact 1RU design with flexible analog, AES3 and AES67 I/O. From a remote broadcast perspective, the leading codecs can connect multiple streams for program and separate communications or can stream to multiple endpoints simultaneously. When bandwidth becomes limited the leading codecs offer network data aggregation in addition to stream diversity.

Record and playback, FTP upload/download, audio processing (EQ, limiting and compression), redundant streaming and data aggregation, are just some of the features buyers should look out for.

RW: How have AoIP technology developments been reflected in the look and function of codecs? 
Gawley: Audio over IP has been Tieline’s bread and butter for over 16 years,  enabling broadcasters to send audio over the public internet, and is nothing new to us.

Tieline had implemented strategies to mitigate packet loss with forward error correction and auto jitter buffer techniques while other codec manufacturers were stipulating use of the five 9 MPLS networks. In 2007 the EBU foreshadowed that ISDN one day would cease to exist and wanted to have a similar level of interoperability over IP. They set up a working party, which Tieline was a member of, that gave rise to the EBU 3326 Interoperability standard over IP with the SIP protocol at its core, and Tieline was the first non-European manufacturer to implement the standard alongside AEQ, AETA, Orban and Mayah.

Fast-forward a number of years, the studio has caught up to where AoIP in the studio is rapidly becoming the norm. Tieline was ahead of the curve implementing the WheatNet-IP protocol in its codecs, from there others added Livewire, Ravenna and Dante. Given all these different proprietary AoIP standards, both the AES and EBU got the industry together and now we have AES67.

RW: And what will codecs look like in the future, if we use them at all? 
Gawley: Codecs will be required for as long as IP networks are imperfect, which is the foreseeable future.

It’s true that some networks can carry full bandwidth PCM audio over fiber, but these networks generally make up the backbone of larger networks and their primary studio-to-studio infrastructure. Transmitter sites often don’t have fiber runs due to their location or the expense of installation. Remotes are performed from anywhere and often rely on cellular and other wired services that still require a codec to reliably transport audio.

Lossy networks like the internet are imperfect and still require “smart” IP technology to reliably transport audio due to jitter and packet loss; this is where one should look for bit-stream diversity.

Despite significant advances and increases in available bandwidth, cellular networks can at times suffer from capacity constraints. This is where data bonding/aggregation comes into play and one should look for this to be included in a codec, rather than as a clunky peripheral piece of hardware that introduces an additional point of failure.

 

The post Codecs Have Become a Swiss Army Tool appeared first on Radio World.

Fig. 1: Custom scripts allow you to change controls on surfaces or to create standalone mixing UIs.

The author is a support engineer for Wheatstone Corp. This originally appeared in the ebook “Console Tech 2021.” It is one in a series of articles about how to get the most out of popular radio broadcast products. 

Consoles come in all shapes, sizes and forms these days, from legacy hardware surfaces to the newer virtual mixers on a laptop and everything in between.  

What worked in your studio yesterday might not work today, and what works today might not work tomorrow. That’s where scripting comes in, both in terms of custom scripts for virtual mixers as well as newer hardware consoles with software configured controls. 

Creating custom scripts to change controls on console surfaces such as our LXE or GSX models or to create entirely standalone mixing UIs is one practical and affordable way to meet these constantly changing requirements.

Nearly every broadcast mixing surface or console manufactured has a set of standard features that cover 90% of the workflow or use requirements for a studio. Generally, these are: input faders, control room and studio controls, mix-minus sends, and logic I/O for tallies and remote control.

Fortunately, the world of audio over IP enabled us to make several improvements on these features. 

[Related: “How to Choose Your Next Console”]

The change from legacy console, where one wires everything to the chassis of the mixer, to a distributed or routed environment with Blades or other I/O units becoming termination points for routing, replaced miles and miles of cabling in some cases.

But even with all the enhancements the AoIP routed studio brought us, at the end of the day the console (or what is now called a “surface”) is essentially doing the same job. That is, mixing your content together and sending that mix on to the next process in the chain.

The job of the console remains the same, but what has changed is how the job is done — and on what.

Multiplicity of applications

For example, with scripting, you can change the default behavior of any hardware button, fader, encoder or OLED screen on the LXE or GSX console surface. 

This can be done in easy-to-use setup software, and changes to the surface generally do not require a restart of the surface itself. In addition to a full array of surface standard functions, users also now have control over button colors as well as the behavior of that button. 

A person could also actually write custom code using the Surface Setup GUI and the Wheatstone scripting language to have the hardware button do more than one function, and then change LED state (such as color) based on the status of whatever it was they intended to control or change.  

A simple example of this is to set up a button to fire a salvo.  

This is a simple point-and-click procedure using the LXE or GSX Script Wizard in the Surface Setup GUI. 

Setting up a button to fire a salvo is a point-and-click procedure using the LXE or GSX Script Wizard in the Surface Setup GUI.

Once the change is sent to the surface, the button becomes a Fire Salvo (macro) button. In addition to firing the salvo to change the audio routing, we can also change the state of logic pins on another Blade in the system and at the same time, change the button to a different color when that logic pin is in the ON state or activated state. 

What’s more, you can go beyond the Script Wizard and into creating a custom piece of software that executes the salvo and changes the state of the logic pin when the button is pressed, plus change the LED color of the button when that logic is active. 

All you’d need is to open the Script Editor and add a few lines of code, as shown below. 

You can can go beyond the Script Wizard, to creating custom software that executes the salvo and changes the state of the logic pin when the button is pressed, plus change the LED color of the button when that logic is active. Open the Script Editor and add a few lines of code.

As workflows and requirements change, you can modify salvos and more, and the surface will automatically update without the need to restart it or the mix/DSP engine.

In addition, with scripting tools such as ScreenBuilder, you can add custom screens directly on the console GUI itself. One of the main benefits of being able to build custom screen interfaces directly on the console itself is that these UIs don’t have to run on a PC in the studio, which most likely is already doing quadruple duty as an Internet/edit/playback PC.  

Screens can be developed using drag-and-drop widgets such as buttons, labels and meters that can be set up with logic controls that modify various aspects of the system for changing audio routing, on/off logic and tallies.

You can set up screens for not only one specific studio, but all of the studios in a WheatNet-IP audio networked system as a whole.  

Across the network

Let’s say you have five stations in a location, and there’s one person in the facility for overnights who monitors all five stations. 

From one control room, the overnight talent could call up a screen to see the status of all five stations at once and swipe through a menu to monitor audio from those stations and to get data from various points in the system. 

This can be done directly on any LXE and GSX console surface in any studio, so if the overnight talent is not in his normal position or studio he or she can still see the system from any room there’s a GSX or LXE. 

Also, these new scriptable consoles have OLED displays for each input fader and two or more for each output module. Each of these displays can be configured independently to display different data sets about sources assigned, program assignments, mix assignments and can be further customized for your own text and graphic displays.You can even add station logos or other images to reinforce station branding, and provide at-a-glance data to the operator.

Another software benefit is the LXE and GSX’s ability to have up to 32 inputs and 16 outputs in their mix engines. This means broadcasters have access to ample inputs and outputs yet are able to keep the physical fader or surface size down to a minimum. By carefully deploying layers to the surface, they can page a smaller layout surface of say 4 to 16 faders to get access to those additional inputs and outputs. This allows studio designers to keep a smaller footprint on the furniture and make additional room, or clean up an already crowded space.

When off-site, operators can also remote in to the studio or physical console using apps such as Remote LXE/GSX, ReMIX or Glass E. These are software extensions of the AoIP network or physical console that can mirror what’s happening at the studio. In some cases, remote operation can be done on an entirely standalone virtual console that contains custom scripting, all of which could be the blocks of the all-virtual studio of the future. 

Robert Ferguson has been in radio for more than 25 years, with experience both behind the board and in front of it as a broadcast engineer and on-air personality.

The post Benefits of a “Scriptable” Mixing Console appeared first on Radio World.

In its strong opposition to allowing geo-targeting on FM boosters, the National Association of Broadcasters told the FCC it is worried about “cannibalization” among radio stations as well as harm to smaller and minority-owned stations.

Radio World is excerpting public comments filed to the FCC in a series of articles. Here, we summarize the section of the NAB filing about cannibalization.

“Although GBS presents its proposal as a permissive option, even voluntary adoption by only one or two stations is likely to disrupt the advertising market for other broadcasters in the same radio market,” NAB told the commission Wednesday.

“In particular, allowing geo-targeting could thrust broadcasters into a collision that disadvantages smaller stations less equipped to absorb the costs of implementing ZoneCasting effectively or reduced ad rates. GBS’s own filings demonstrates the risks.”

It pointed to an example from GBS showing a high-powered station broadcasting from downtown Manhattan that could use boosters to create zoned coverage areas in New Jersey, Connecticut and on Long Island:

“Although GBS offers this image to illustrate the station’s opportunity to use boosters to geo-target news and information to these respective areas, the station would also be able to sell geo-targeted ads,” NAB told the FCC.

“It is easy to foresee the negative impact on smaller stations licensed to Edison, N.J., and Mount Kisco, N.Y., and other distant suburbs. Such broadcasters must already compete with nearby stations for precious ad dollars from grocery stores, car dealers and other small businesses in the local area.

“If the booster rule is amended, they could be pitched into battle against much larger, New York City-based broadcasters for this critical local business. And contrary to GBS’s claims, some broadcasters believe that any such opportunity to sell zoned ads to new customers will largely be one-way because smaller stations do not have access to the capital necessary to implement geo-targeting as effectively, or capture enough new advertising business to justify the effort.”

[Related: “GBS Gathers Support for Geo-Targeting”]

NAB also questioned the usefulness of ZoneCasting for stations in small and mid-sized markets. It said its members in these markets view ZoneCasting as a “big city play,” at best.

“It would be unusual for small and mid-sized radio markets to have multiple pockets of population sufficient to support the investment required to deploy GBS’s system. GBS points to certain radio markets that cross state borders or cover multiple economic areas where geo- targeting could possibly make sense. Again, however, most broadcasters predict that larger stations would enjoy the lion’s share of any such benefits, at the expense of smaller stations.”

NAB argues that “nearly all” radio broadcasters consider GBS’s proposal “as a lose-lose proposition in which the only winners would be the technology provider and advertisers.”

The association also disputes that geo-targeting will help minority-owned broadcasters, a benefit that has been mentioned publicly several times by Commissioner Geoffrey Starks.

NAB acknowledged that public interest organizations led by MMTC have expressed support of GBS’s petition. “MMTC explained that minority station owners often entered broadcasting later than others, leading them to locate their tower sites located some distance from downtown. MMTC states that ZoneCasting would enable these broadcasters to target different programming to different audiences, and adds that such owners may also be able to entice small and minority owned businesses to purchase less expensive, zoned ads.”

NAB said it shares MMTC’s goals to help promote minority ownership of stations but says the booster rule change would likely be counter-productive.

“First, a minority broadcaster with a transmitter on the fringe of a market would already have the incentive and ability to obtain a booster so as to provide a stronger signal into the urban core of a market. Given that the FCC’s rules permit stations to deploy a booster at their convenience, we presume that any such broadcaster has already done so where the investment has been justified.”

NAB said that any incremental ad sales to small businesses from geo-targeting would not change that calculation, particularly in light of the risks and costs of implementing geo-targeting.

It noted that GBS has offered to provide vendor financing to certain FM stations, fronting the capital to design, build and operate a booster, in exchange for a share of the marginal ad revenue it generates.

NAB asked what would happen if GBS encounters financial problems and requires accelerated payment, and what would the station’s obligation be if revenues are insufficient to repay GBS or the station discontinues service.

“We understand that vendor financing has been used in other telecommunications contexts. However, to NAB’s knowledge, it would be highly unusual if not unprecedented for the FCC to alter a long-standing rule in order to approve a new broadcast technology based on the promises of a single, private company to fund its rollout.” It said the FCC should not rely on GBS’s about vendor financing plan.

“Finally, MMTC does not address the unintended consequences that ZoneCasting could impose on minority broadcasters. Just like other similarly situated, smaller radio stations, minority owned stations could face new competition from large stations in other parts of a market. There would be nothing to stop a large downtown station, with the resources to fund its own booster and effectively sell zoned ads, from building a booster near a minority-owned station and using the booster to seize ad dollars from small or minority-owned businesses in the area,” it wrote.

“Moreover, a larger station could better afford to charge very attractive prices for zoned ads to win such business. In the end, ZoneCasting could be little more than a vehicle for large stations to increase their dominance at the expense of smaller stations, including those owned by people who are members of historically underrepresented groups. Such an outcome would not serve the public interest in diverse radio service.”

[Related: “ZoneCasting Would Level the Playing Field for Radio”]

The post NAB Details Its “Cannibalization” Worry appeared first on Radio World.

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Requests the substitution of channel 18 for channel 13 at Kearney, Nebraska, in the DTV Table of Allotments

Requests the substitution of channel 32 for channel 9 at Cedar Rapids, Iowa, in the DTV Table of Allotments

Requests the substitution of channel 27 for channel 8 at Jonesboro, Arkansas, in the DTV Table of Allotments

Requests the substitution of channel 20 for channel 7 at Amarillo, Texas in the DTV Table of Allotments

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Issued a Notice of Apparent Liability for Forfeiture in the amount of $1,500 to Iglesia Sinai Pentecostes, Inc., for failure to timely file a license renewal application for Station WLDC-LP, Goshen, Indiana

Requests an amendment of the DTV Table of Allotments to delete channel 10 at Peoria, Illinois, substituting channel 10 at Oswego, Illinois. Further requests modification of WAOE's license to specify Oswego as its community of license

Requests the substitution of channel 27 for channel 12 at Augusta, Georgia, in the DTV Table of Allotments

Maquoketa Broadcasting Company enters into consent decree to resolve political file investigation

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Requests the substitution of channel 21 for channel 9 at St. George, Utah, in the DTV Table of Allotments

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Requests the substitution of channel 32 for channel 11 at Cape Girardeau, Missouri, in the DTV Table of Allotments