Aggregator

WWV building. Read about the service by clicking the image.

Here is my response to the letter to the editor “WWV Is Nice But Not All That Critical.”

The letter raised an eyebrow with me. The notion of eliminating the HF (2.5 to 20 MHz) service of the NIST National Institute of Standards and Technology station WWV is a bad idea.

I regularly use the 5 and 10 MHz signals to calibrate time bases in my spectrum analyzer, signal generators, receivers and frequency counters. It is a time-proven technique to zero-beat their reference oscillators with WWV and still valuable today in commercial and amateur radio use.

Yes, the Global Positioning System does that job, but it is vulnerable to enemy attack. WWV is the fallback to save us from problems of synchronizing networks, including the internet in the event that GPS becomes unusable.

The 60 kHz WWVB is the source for automatically setting “atomic” watches, wall clocks and other devices. Since we agree on that, then keeping the HF transmitters of WWV working is a small price to pay in the overall scheme of things. They are all at the same site in Fort Collins, Colo., operating from the same frequency standard and maintained by the same crew.

GPS is not infallible and is subject to interference, tampering or having satellites knocked out of the sky by those who do not like us.  We’ll be glad we still have WWV when things get rough.

Comment on this or any article. Write to radioworld@futurenet.com. Mark Persons is a frequent contributor to Radio World. Read his recent articles.

The post Letter: Don’t Dump on WWV appeared first on Radio World.

An image from the new NABLF resource center.

A new website aims to help media companies and professionals “create and sustain a diverse and inclusive workplace.”

It was created by the National Association of Broadcasters Leadership Foundation. The Diversity, Inclusion and Equity Resource Center promises to connect organizations with associations and consultants that can help with what has come to be called their DEI — diversity, inclusion and equity.

The announcement was made by NABLF President Michelle Duke, who recently was named the NAB’s chief diversity officer.

The site is essentially a pool of links to third parties and a summary of what kind of resources could be found at those destinations. Topics on the site can be filtered by associations and organizations; consultants; resources; and training and courses.

A sample is Brown University; its listing on the resource site links to the school’s Diversity and Inclusion Toolkit, which includes best practices for recruitment, communicating across cultures and building a respectful workplace, including guidelines for working with LGBTWQQ+, veterans and individuals with disabilities.

We counted about 120 such links so far, and NABLF is inviting more.

“These connections can help companies reassess business strategies, launch diversity initiatives that embrace unique perspectives and voices, and provide education programs for leadership teams and staff to better integrate DEI in their operations,” the foundation stated.

The resource center also offers information about personal professional development courses.

The post NAB Foundation Launches Diversity Resource appeared first on Radio World.

Radio broadcasters in the United States continue to reevaluate capital expenditure budgets amid the COVID-19 pandemic. Cap-ex spending drew down drastically in the first half of this year, according to financial reports from several major commercial broadcast groups.

Expense management has become crucial during the economic downturn caused by the virus, according to industry observers. The impact of the crisis on the radio technology marketplace has been severe, they say; and although equipment manufacturers and vendors expressed some optimism in early summer that spending on equipment and projects would bounce back later in the year, the upbeat signs seemed to have dampened as summer wore on.

Revenue Shrinkage

Several former engineering executives said broadcasters are being forced to question and justify each line item in their budgets, from the bottom up, as their employers seek to mitigate the economic impact of COVID-19. Most groups froze capital expenditures or at least prioritized critical projects that needed funding.

iHeartMedia, owner of more than 850 radio stations in 160 markets, among its many other platforms, announced in April it would reduce cap-ex by an expected $80 million for the rest of 2020. As of May, when it reported first quarter earnings, the company was projecting capital expenditures of $75 million to $95 million this year.

Meanwhile, Entercom Communications, owner of approximately 230 stations, said it would trim cap-ex by over 40% due to the pandemic “to a revised range of between $25–$30 million for 2020,” according to an April filing with the U.S. Securities and Exchange Commission.

The broadcasters contacted by Radio World were reluctant to discuss current spending plans, but it is clear that broadcasters had taken drastic measures since March, to hold onto cash where necessary.

“These companies are facing severe revenue shrinkage, which means they are being forced to conserve cash. It’s not clear when spending might resume,” said one person connected with the industry. “The economic crisis caused by the pandemic is driving all business decisions.”

Signs of spending cuts are quite evident in public filings by broadcasters. Spanish Broadcasting System said it was “limiting capital expenditures” in its first quarter 2020 filing with the SEC. Cost-cutting at Cumulus Media, which owns 424 stations, included a cut of 40% in capital expenditures the remainder of this year, according to a press release from the broadcaster. Townsquare Media, which has 321 radio stations in 67 markets, has “reduced all planned capital expenditures,” according to a statement from CEO Bill Wilson.

[Related: “Cumulus Will Sell Its Towers to Vertical Bridge”]

“Pared to the Bone”

Former engineering executive Milford Smith, now principal with Smith, Khanna and Guil Inc., said broadcast groups are likely focusing on “compliance issues” and any truly critical projects.

“Close behind are any projects or issues involving reliability — on air or online. This includes PPM systems, transmission systems and interconnection systems. Beyond these core items, most everything else can be considered optional.”

Smith said that “an old automation system and console that has been growing whiskers” will likely have to make it through another year before being replaced.

Equally concerning are the seemingly endless rounds of staff reductions, Smith said.

“Many stations and companies have pared staff to the bone. They are severely short-staffed. A multi-station cluster in a competitive market can only be expected to operate reliably and effectively with adequate technical expertise,” Smith said.

Bert Goldman, president of Goldman Engineering Management, said radio businesses have been hit hard.

“Loss of revenue has impacted all facets of station operations. And there is a drastic change in technical priorities as staff is moved off-premises and as many operations as possible go remote,” Goldman said.

Broadcasters were smart to freeze non-critical spending, both operating and capital, until the long-term situation is clearer, Goldman said.

“Specifically, until the impact to the business is determined, all capital spending, unless a project was actively in progress and could not be stopped, would probably be frozen. Any capital funds unspent would likely be immediately reallocated to emergency capital costs associated with pandemic response, such as updating playout systems, computers for home operation and remote equipment. Operationally, internet access would likely need upgrading at staff homes,” he said.

Goldman said many broadcasters had to move fast to replace older, less-flexible on-air playout systems so that operations could continue remotely.

“It is likely that emergency capital was spent during the crisis, which will impact available capital moving forward,” he said.

Gary Kline, a technical broadcast consultant and former DOE at Cumulus, said it can be hard for managers to find a consensus on which projects are critical versus those that can be paused.

“A DOE is almost surely to be inundated with feedback from the markets disagreeing with their decisions. What an engineering manager thinks is not mission-critical may be seen by the local market as critical,” he said. “And as the cap-ex budget contracts, the tougher the decisions are.”

Kline said good communication between executive leadership and the director of engineering are important. While senior leaders must provide engineering with updated guidelines for spending and how to prioritize, a DOE should be able to give management his or her feedback; the discussion should be collaborative and ongoing.

“Unpredictable”

Equipment suppliers are being realistic about the situation, said Bob Cauthen, president of equipment vendor SCMS Inc.

“Budgets and projects have definitely been cut and postponed. Some projects have been totally cancelled. I think all broadcast dealers and manufacturers have felt the pinch during the second quarter,” Cauthen said this summer. “It has been felt across the board in small, medium and major markets.”

Cauthen said trying to predict when things return to normal is like trying to figure out when the COVID-19 pandemic will end.

“It truly is unpredictable at this point, with all the variables. My personal guess is it will gradually improve, and broadcast will have a good fourth quarter, especially with political ad income peaking,” he said.

The pandemic has caused something of a business boom for companies selling remote broadcasting equipment.

“I suspect that Comrex is one of the few broadcast equipment manufacturers to have not been adversely affected by the pandemic,” said Chris Crump, senior director of sales and marketing at that company. “We had some logistical challenges in March and April as we tried to come to grips with the effects of COVID-19 and how best to keep our employees and their families safe. All the while, we had to find a way to increase our production output to keep up with orders.”

Crump said there are still a lot of unknowns regarding parts supplies, which have been exacerbated by major shipping carriers that no longer guarantee delivery times.

“Luckily our team has been able to work around extended parts lead times caused by this global crisis so we can meet our shipping requirements,” he said.

Comment on this or any story. Email radioworld@futurenet.com with “Letter to the Editor” in the subject field.

Keep up with technology trends in radio with Radio World’s library of free ebooks. Recent topics include trends in codecs and STLs; broadcasting from home; how to ensure RF readiness for your air chain; and how artificial intelligence is showing up in radio technology. Read them here.

The post Radio’s Infrastructure Spending Is Slammed by Pandemic appeared first on Radio World.

This notification appeared in Alabama Engineering Academy’s weekly newsletter, Monday Morning Coffee and Technical Notes,” To subscribe, contact Larry Wilkins at lwilkins@al-ba.com.

All broadcast engineers understand that the FCC is serious about tower lighting, monitoring, and record keeping to demonstrate that monitoring has been done properly.

The FCC rules 17.47 inspection of antenna structure lights and associated control equipment.

[Read More Tech Tips Here]

The owner of any antenna structure which is registered with the commission and has been assigned lighting specifications referenced in this part:

(a)(1) 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 ensure that all such lights are functioning properly as required, or alternatively

(2) 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.

(b) Shall inspect at intervals not to exceed three months all automatic or mechanical control devices, indicators, and alarm systems associated with the antenna structure lighting to ensure that such apparatus is functioning properly.

The commission also requires the maintenance of a log of the daily inspection by a chief operator or a log generated by the monitoring system weekly. It is also a good reminder that due diligence in an acquisition must include tower lighting monitoring records.

Most importantly, should the daily observation indicate an extinguishment or improper functioning of any top steady burning light or any flashing obstruction light, regardless of its position on the antenna structure, and not corrected within 30 minutes you must report it to the FAA (1-877- 487- 6867).

Click here for a tower outage form.

Larry Wilkins, CPBE, is director of engineering services for the Alabama Broadcasters Association.

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

 

The post Tech Tips: Tower Light Reminder appeared first on Radio World.

The author is chairman of Digital Radio Mondiale. Her commentaries appear regularly in Radio World.

Radio digitization news continues to trickle in, even if COVID-19 has frozen many projects and turned radio events, even world ones like IBC 2020 or CES 2021, primarily into Zoom sessions.

But those interested in digital radio can continue to read the “for-and-against” regarding the possible introduction of pure HD Radio on medium-wave in the U.S., still under discussion. Or they can catch up with news about the future of DAB+ in Switzerland or France.

DRM is there, too, with the excellent trials and measurements carried out recently by the Indonesian public broadcaster (RRI) at three stations, where DRM is delivering audio, data and emergency warnings in the FM band. There are other DRM developments in India, Russia and China.

Depending on what continent or technology is of interest, there is plenty of news about digital radio. But, ultimately, what we have is a patchy quilt of standards that all aspire individually to be continental or even global. Why is there this fragmentation?

“Intrinsically Partial”

The reasons are many.

HD Radio and DAB/DAB+ offer intrinsically partial digitization solutions. HD Radio was invented and deployed in the U.S. in the FM band; and now the discussion is about pure HD in medium wave. Is it possible; is it wise? Will it work? These are questions are now in the FCC in-tray.

On the other hand, DAB/DAB+ was conceived just for the local VHF band III, when vacant or partially vacant, as television goes digital and moves out to higher frequency pastures.

DRM is the only standard that can be deployed in all broadcasting bands and can offer alone local, regional, national and international coverage, if necessary, though there are few countries in the world that use simultaneously all the existing HF, AM, HF VHF bands (I, II and III).

To make things even more complicated, DRM and DAB/DAB+ are open standards, sharing a lot of features and open to cost-cutting IP license synergies. HD Radio, on the other hand, is a proprietorial standard, i.e. its DNA is owned by an U.S. commercial company, Xperi. Like DRM it offers an in-band solution, different from the multiplexed DAB+ model.

Confused? Imagine then the regulators, governments and other entities that must choose which digital path to take, when each of the almost 200 countries in the world is genuinely unique.

It is not just about size, topography or history. It is also about each country’s legacy and radio journey, with its specific characteristics inextricably linked to its culture, customs, languages, expectations.

Unending Criteria

So, which is the best standard?

ITU recommends them all three. The question is rather what the needs are (broadcasters’ and listeners’ alike) that digital radio is required to fulfill in each small, medium or large country.

The criteria might be linked to spectrum and broadcast capacity, energy use and savings, features (audio but also data), disaster warning capability or, nowadays, capacity to deliver besides general information, entertainment education, too.

And then comes the tricky question of the receiver availability, in cars, in homes or in mobiles, though no manufacturer will flood a market if a country administration or government has not indicated its digital radio preference. And those receivers won’t sell, if there is not enough coverage with digital broadcasts.

The list of criteria is unending. Focusing on the listeners’ needs and expectations is probably the best starting point.

Recently, the government of South Africa has looked at some of these criteria. After many trials, deliberations, working visits, impressive activities undertaken by various lobbies (like those representing the 11 million disabled people in the country), committed organizations (community, religious, commercial stations), industrial groups and enthusiastic individuals, it pragmatically has recommended the two open standards together, DRM and DAB+, for full potential and good country coverage.

In some places this development was presented as “South Africa Publishes Policy Directive for DAB+”, which it is, but not only DAB+. That’s a bit like saying 24 hours has only night or only day.

The DRM Consortium sees the dual recommendation from Pretoria as a historic decision for the whole of the African continent, an example to other countries in Africa, Asia and Europe. They have, or they will have to, opt for digital radio sooner or later. If they go for a combination of DRM and DAB+, all the conditions exist to offer full services to all citizens of a country, no matter where they are.

Some are wondering if there will be receivers to receive both DRM and DAB+. As chipsets are the heart of any receiver, the answer is yes.

The big infotainment chipset suppliers exist. For standalone receivers, the solution must be to use more innovative chipsets than what we have seen for the last 20 years or so. Software-defined receivers can easily surmount the dual (or any) standard questions.

There are already millions of DAB receivers (an achievement to be commended), mostly in places like the U.K., Australia and Norway. And there are over 2 million cars with DRM receivers in India, a pure DRM country. This is not trivial. In the U.K., standalone receivers are mainly DAB, although the newer DAB+ version is also on sale. Car receivers can be software-upgraded; and cars are driving radio.

So there are solutions; and the “multiple standard” approach might become the real breakthrough for digital radio.

There is already a BC and AC distinction — “before COVID-19 and after COVID-19.” In the new normal, with its tough economic realities but also renewed entrepreneurial spirit, there will be optimum solutions so that digital radio policies like South Africa’s do not remain only on paper.

Radio World welcomes comments on this or any story.

The post Can Digital Radio Standards Coexist? appeared first on Radio World.

Kirsten Smith

“Best of Show” Up Close is a series of Q&As with participants in Radio World’s annual springtime Best of Show Awards program.

Broadcasting Bionics nominated Camera One. Kirsten Smith is business development manager for the company.

Radio World: What is Camera One and what is its targeted application?

Kirsten Smith: Camera One is a small-scale visualization system designed specifically for radio studios or podcasters. It’s designed to be simple to use and require minimum hardware and configuration/setup. This is reflected in it being great value for money.

RW: What sets it apart?

Smith: Camera One presents the user with an essential core feature set, giving the smaller stations  and podcasters the freedom to create great video assets. Broadcast Bionics’ larger system, Bionic Director, gives a larger range of control and graphics and is generally aimed at the mid to large enterprise.

The output of both products produce shareable clips for social media and allows for live streaming.

RW: In light of the pandemic, are there specific relevant capabilities we need to know about?

Smith: Where budgets are being squeezed as a result of reduced revenue, Camera One is great value for the money, and requires only a small investment. Of course the output could easily be monetized by sponsorship.

From a technical standpoint, it’s possible to remote connect to the studio machine which is running the software and because the camera switches automatically using the unique Broadcast Bionics algorithm, there’s no need for an operator to be in the studio with the presenter. (Social distancing sorted!)

RW: You highlight its HTML5 interface, why is that notable?

Smith: The user interface is written in HMTL5, which means that it can be used in a browser on any device — PC, MAC, Tablet-IOS/Android. The software runs on a machine in the background, and therefore there’s no need for the installation of an app on a designated machine. This gives great flexibility and product mobility.

There is no limit to the number of users accessing the system at any time, enabling collaborative working in real time.

RW: What does it cost? Is it shipping?

Smith: Camera One is moving to the beta phase right now, and we’re expecting to have a staged release later this year. The software licensing cost for a four-camera system is $995 / £765 / €880.

RW: What else should we know?

Smith: Camera One is compatible with any console. It uses the Blackmagic ATEM Mini or ATEM Pro and any HDMI camera, and coming soon the Blackmagic Television studio, which also supports SDI cameras.

Having spent the early days of the pandemic enabling our users to work remotely, and working dynamically to produce software quickly to enhance our offering — such as standalone Skype TX, Caller One, Anywhere — for remote working, Broadcast Bionics is now back to concentrating on bringing more new and exciting innovation to the industry.

By missing NAB and IBC this year, we’re really looking forward to next year’s shows where we can show off our new products.

[Read about all the nominees and winners in the award program guide.]

 

The post “Best of Show” Up Close: Broadcast Bionics Camera One appeared first on Radio World.

The PodTrak P4 is a new portable multitrack recorder from Zoom North America aimed squarely at podcast production. Weighing just over half a pound, the compact recorder combines a mixer, mic inputs, headphone outputs, sound pads, Bluetooth and more in a unit measuring roughly 4.6 x 6.1 inches, making it a portable option for content creators on the move.

The unit records to SD cards up to 512 GB or can work as a two-input, two-output audio interface, connecting to a computer. Up to eight tracks can be recorded in 16-bit /44.1 kHz audio WAV format and all input sources can be recorded simultaneously on separate tracks.

[Check Out More Products at Radio World’s Products Section]

The P4 provides four 48V phantom-powered XLR inputs, each of which have their own mute buttons and control knobs providing gain up to 70 dB. Correspondingly, there are four 3.5 mm-1/8-inch stereo mini headphone outputs with individual volume controls as well, as there is a mix-minus feature to help prevent echo and feedback. Remote interviews via phone can be recorded as well via a TRRS cable or via a USB cable attached to a computer running conferencing software. Users who have an optional Zoom BTA-2 Bluetooth Transmitter/Receiver can also wirelessly connect a smartphone to the PodTrak P4 in order to record remote guests, though an Apple Lightning to USB camera adapter required for iPhone users.

For users who want to work in music, ads, jingles, stingers and the rest, a total four assignable stereo sound pads allow them to trigger 11 onboard sounds, as well as load in their own audio for triggering by the pads as well.

The P4 can run up to four hours on a pair of AA batteries or can be powered externally by a USB Type C cable as well as an AC adaptor.

Expected to debut in mid-October, the Zoom PodTrak P4 Portable Multitrack Podcast Recorder has an MSRP of $199.

Info: https://zoomcorp.com

The post Zoom Launches PodTrak P4 Portable Multitrack Recorder appeared first on Radio World.

The Radio Advertising Bureau plans to acquire the National Radio Talent System. The roaming radio broadcast training course will continue to operate under its brand name and network of Radio Talent Institutes with oversight by the RAB. Dan Vallie, National Radio Talent System founder and president, will advise the RAB as it integrates the institute into the organization.

College students, recent graduates and radio interns apply to be accepted into the 10-day institutes. Sessions include on-air, programming, sales, writing, news, sports, promotions, videography, podcasting, social media, engineering and management. Each student participates in RAB training and takes the exam to earn their Radio Marketing Professional Certification.

In a statement, RAB’s President and Chief Executive Officer Erica Farber said, “An integral part of the RAB’s mission is providing the industry with the tools and resources to help broadcasters attract new sales talent to the medium and enhance radio’s professionalism through training and support. The integration of the National Radio Talent System into the RAB delivers on the mission in so many ways…”

“The future of our companies is dependent on the next generation of committed, prepared and talented radio professionals,” said Susan Larkin, Entercom Communications’ chief operating officer and RAB board chair. “The National Radio Talent System is unique in that it provides a radio talent farm for the industry, an incubator of well-rounded, well-educated college talent with a passion for radio.”

As previously announced, all 2020 programs were rescheduled for 2021 due to COVID-19.

 

The post RAB to Acquire National Radio Talent System appeared first on Radio World.

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It’s been a few years since we’ve discussed RDS best practices, but the items we have covered in this series of articles over the last decade are more relevant than ever.

At this point, just about every new automobile manufacturer supports some form of RDS when a receiver is tuned to an analog FM station.

The big shift is that visibility and support for the Program Service (PS) field and PS scrolling are fading in favor of RadioText (RT) and RadioText Plus Tagging (RT+ Tagging).

Larger 6- to 12-inch LCD displays are in almost every vehicle you see on the lots now. These have multiple lines for text messages, and the eight-character PS scrolling really does catch the eye. The full station name, title and artist with RadioText and RT+ Tagging really helps stations look better in the dash.

Also, with National Highway Traffic Safety Administration guidance and regulations related to driver distraction in the United States, many automotive manufacturers have dampened or defeated PS scrolling from working in their vehicles.

Even with RadioText, modern receivers want more information, and RT+ Tagging is supported in more vehicles. Radio World has covered a variety of topics on how to optimize RDS for these fields, and other tips and tricks. You can find that information in a 2018 ebook at radioworld.com.

Another great resource is “NRSC-G300-C: RDS Usage Guideline,” last updated April 2018). It can be found online at www.nrscstandards.org, under Standards & Guidelines.

RDS Subcarrier Injection

Let’s dig into detail about the importance of proper RDS subcarrier injection. This is still a common problem I work with, both in my professional capacity at iHeartMedia and personally as I travel and see various RDS implementations across the country.

While it’s difficult to come up with hard facts, a lot of stations are not following the NRSC-G300-C guidelines in Section 4 to ensure there is proper synchronization with the 19 kHz pilot and maintaining 6% (4.5kHz) to 7% (5.25kHz) injection of the 57 kHz RDS subcarrier.

First, let’s understand how the RDS subcarrier injection is described numerically.

Often in North American broadcast products, documents and discussion, you will see the RDS subcarrier injection referenced in terms of percentage, such as 6%.  This is referenced as 6% out of 100% modulation referenced to 75 kHz deviation. So, 75 kHz x 0.06 (six percent) = 4.5kHz deviation. And 75 kHz x 0.07 (seven percent) = 5.25 kHz deviation.

You will often see these methods used (percentage and referenced as deviation) when discussing injection, sometimes interchangeably.

Suppose you have a measurement made in kHz deviation and want to translate that into percentage. For example, a modulation analyzer may say the RDS injection is 4.875 kHz but not tell you the percentage:

4.875 kHz / 75 kHz = 0.065 x 100 = 6.5%

The international markets are more focused on kHz deviation levels. You may encounter product measurements, manuals, documentation or other articles referencing kHz deviation, and now you know the basic math converting between these two. We’re really discussing the same thing, just a different reference level.

Regulatory Guidance

In the United States, no Federal Communication Commission authorization, notice, application or license is required by a broadcast station licensee wishing to transmit a subcarrier. Subcarriers are also known as Subsidiary Communications Authority or SCA. A subcarrier or SCA is a separate audio or data channel transmitted along with the main audio signal over a broadcast station. RDS is considered an SCA, and stations can start or stop transmission at any time as per 47 CFR Section 73.293.

The FCC allows total FM carrier deviation above 100% modulation referenced at 75 kHz under 47 CFR Section 73.1570(b)(2)(i) and (ii). The total peak modulation may be increased 0.5 percent for each 1.0 percent subcarrier injection modulation, but in no event may the modulation of the carrier exceed 110 percent (82.5 kHz peak deviation).

What does this mean in practical terms?

If your 57 kHz RDS subcarrier is the only subcarrier on the station, and you desire 6% injection, half of that injection (3%) can be added to your overall total modulation envelope. Thus, the maximum permitted FM modulation envelope on the station is 103%, or 75 kHz x 1.03 = 78.25 kHz deviation.

Field Observations

My general advice and guidance for most full-power stations is to use 6% (4.5 kHz) injection as optimal for most applications.

You may want to consider up to 7% (5.25 kHz) injection if you are on a noisy channel with nearby co-channel interference, have extreme terrain challenges in your service area or are trying to provide the best experience in the far field (i.e. the desired, or largest portion of your audience is at or beyond your protected service contours).

Another area where higher injection helps is on lower-powered stations such as translators. Many FM translators are used well beyond their official “protected” 60 dBu service contour, so having a high injection level on these stations is encouraged.

Raising the injection of the subcarrier increases the signal-to-noise ratio of the digital subcarrier and makes it easier for receivers to decode it error-free, especially in the far field and in challenging FM environments (multipath, interference, low signal, etc.).

While this evidence is anecdotal, I have never seen a situation where going above 7% (4.5 kHz deviation) has been helpful. And I have found stations unintentionally injecting over 10%, actually causing some RDS receivers to stop working. In a sense, if the signal is too high, it can degrade decoding performance in select receivers.

Similarly, I find a lot of stations out there that are injecting below 4% (3 kHz deviation), where RDS decoding is very difficult.

Both situations (subcarrier injection too high or too low) can cause spotty RDS displays. Information may never populate or may not update quickly upon change. Focusing on your RDS injection and knowing it is in the 6% to 7% range is very important.

Measuring Injection

Knowing how to set up your RDS encoder injection properly is important. It’s a key performance item for RDS displays to work.

With the growing receiver base, and with more broadcasting offered enhanced metadata with station branding, title, artist and even advertiser messages, you want to make sure every station you maintain has the RDS injection set properly.

RDS injection measurement has long been an issue. Many engineers in the field do not have access to tools to measure this important metric. We will discuss some available products, new ones that you can buy as well as common legacy offerings you might be able to find on the shelf somewhere.

One important note: It is highly desirable to make this measurement at the RF sample output of your exciter or transmitter This gives you the most accurate reading before environmental effects are put into the equation (such as multipath).

Many of these products will work anywhere within the coverage area, and you could locate them at the studio, for example, if you have good RF reception there. However, you will notice all of your FM modulation parameters are subject to more variations. For the most stable results, it’s best to measure this at the transmitter site.

Note that when using an RF sample output, be sure you do not exceed the maximum input specifications of the measurement device. When in doubt, use attenuators to be safe, and slowly decrease the attenuation to get a high desired signal without overloading the unit. Variable attenuators are the best for this application.

Belar

Belar is a well-known vendor in this space, and it offers highly accurate RDS injection measurement tools in their flagship FMHD-1 product. This is some of the most comprehensive details I’ve seen out of a monitor specifically related to RDS injection.

As shown in Fig. 1, you can view the current average RDS in the Analog Bar Graph menu, and you can view a detailed histogram of RDS injection, measured in percentage, over time.

Fig. 1: The Belar FMHD-1 shows the current average RDS in the Analog Bar Graph menu.

These details can be viewed using a software application connected to the FMHD-1, and it can be accessed remotely if attached to a computer that has Remote Desktop, VNC or another screen sharing solution installed and running.

Belar offers FMCS–1L and the RDS-1, which interface with their Wizard line of analyzers that show RDS injection.

Deva

Deva has several products in its portfolio that offer RDS injection monitoring. Shown in Fig. 2 is the Band Scanner Pro.

Fig. 2: The Deva Band Scanner Pro shows numerous modulation measurements, including RDS injection and decoded RDS text.

What I like about the Band Scanner Pro is that it’s portable and can go into your laptop bag and go from site to site easily. It travels well on planes and such. It’s a very small, portable tool that offers easy access to diagnostics of all RDS parameters and allows the user to dig into deeper binary information contained in the RDS subcarrier.

Deva also makes the Radio Explorer line, the DB4005 rack-mount monitor that can be accessed remotely, and other products that can measure RDS injection.

Inovonics

Inovonics offers the 531N FM modulation monitor, which has a native HTML5-based web browser to remotely access and view measurements. Included in those measurements are the RDS injection, as shown in Fig. 3.

Fig. 3: The Inovonics 531N shows RDS injection and on a different screen decoded RDS text.

Inovonics also made a model 510 RDS monitor. While no longer in production, you might find legacy units around the shop or in the rack. This model can calculate RDS injection when calibrated properly.

Worldcast/Audemat

Worldcast and Audemat have long been in the RDS space. Many engineers are familiar with their line of RDS encoders, but they have made several products that can monitor RDS as well.

A popular legacy product that has many field installations is the Audemat Golden Eagle.  It offers RDS injection measurements on its front panel as shown in Fig. 4. The Golden Eagle HD also offers it in the remote client software package.

Fig. 4: The Audemat Golden Eagle includes a bargraph display of RDS injection.

Audemat also has the Navigator and Navigator HD, FM MC5 and other products, current and legacy, that measure injection.

A recent breakthrough in RDS encoding products on the market, the Audemat RDS Encoder 2019 model, includes an FM tuner in the encoder that can be used for continuous RDS injection measurements. This really is a nice touch, and I’m happy that Worldcast/Audemat included an integrated receiver in this product.

This helps close the gap of stations not having the proper equipment to measure RDS injection, as well as other parameters. I’ve heard countless times where an engineer is on-site installing an RDS encoder or making changes to the air chain, only to tell me they do not have a modulation monitor, nor an RDS receiver in their car. The new Audemat RDS Encoder resolves both problems. The tuner’s results are available in the same HTML5 interface that you use to configure the RDS encoder. So, those stations who chose this product can have a 1:1 ratio of RDS encoder and RDS monitoring.

Also, as discussed, having the modulation monitor at the transmitter site yields more accurate results. Having the RDS encoder at the transmitter site is also highly desired and offers optimal transmission of the RDS signal.

Combining these functions into a single device at the transmitter site solves many problems that we have had in the industry of not having the correct test and measurement equipment for RDS.

In Fig. 5, you can see the FM Tuner tab showing the RDS injection as well as decoded PS, RadioText, PTY Code with format name resolution, TA/TP status modes, Alternate Frequency (AF) listings decoded, as well as displaying the PI Code with legacy NRSC-4 callsign back-calculation (does not work on some stations as per NRSC-4-B and NRSC-G-300-C).

Fig. 5: The new Audemat RDS encoder includes a tuner that shows RDS injection and decoded RDS data.

This is a nice combination of hardware to have in the field, and I strongly recommend that other manufacturers consider an integrated tuner to close the test and measurement gap that nearly every broadcast engineer in the field has encountered.

What if I don’t have an analyzer?

The list above offers a comprehensive (but not all inclusive) view of products that are available on the market to measure RDS injection.

Inevitably you may occasionally find yourself in a situation where you do not have a professional injection measuring device at your fingertips. Maybe the station you are working on does not have a monitor that measures injection, or maybe you just forgot to bring it to the site.

While it is typically not quite as accurate, the method discussed below can achieve very good results, especially on a modern exciter.

Temporarily kill the analog FM audio on the station, leaving the stereo pilot and RDS subcarrier online. Many exciters offer a 100% scale (default) and an extended scale that shows 10% to 20% modulation. With the analog audio silent, and if you know the FM pilot injection (you should; it’s an FCC requirement), you can reasonably calculate the RDS injection by subtracting the total modulation minus the FM pilot.

For example, in Fig. 6, we show a GatesAir Flexiva FAX-50 exciter on the test bench, with no analog modulation, 8% 19 kHz stereo pilot injection. The extended modulation scale reads 12.5%, so it can be reasonably assumed that the RDS subcarrier is 12.5% – 8% = 4.5%.

Fig. 6: An example of using an expanded baseband modulation scale to measure RDS injection levels in a pinch. This is from a GatesAir Flexiva FAX-50 exciter on the test bench.

When you are using this method, I strongly recommend running a quick confirmation test by disabling the RDS encoder’s output in software, or disconnecting the SCA BNC output to your air chain temporarily. Total modulation should in this case drop from 12.5% to 8%, thus confirming the 4.5% difference is indeed the RDS subcarrier and not some other source of signal or noise in the measurement.

This trick will get you out of a bind, although it has some downfalls. I strongly recommend using an RDS injection monitor for accuracy, and to minimize disruption to your listeners. After all, this last example requires you to create dead air on the live broadcast station, and often you need to adjust in the encoder’s output, or processor/exciter input stage, prolonging the period of dead air. There’s also the potential of measurement error, since the expanded scale of the exciter is not specifically looking for the 57 kHz subcarrier, and does not decode RDS. Precision matters now that RDS is so visible in the dashboard.

Alan Jurison is a senior operations engineer for iHeartMedia’s Centralized Technical Operations Engineering team. He chairs the NRSC Metadata Usage Working Group. His opinions are not necessarily those of iHeartMedia, the NRSC, Radio World or our sponsors.

The post Best Practices for RDS Subcarrier Injection appeared first on Radio World.

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