Aggregator

.

First I’ll tell what you already know. Back in the day, AM broadcasting was king and FM was commercial-free. Things changed in the 1970s as FM grew in popularity. Here we are 40+ years later with many AMs struggling. Some have gone away because they were no longer financially viable. To make matters worse, AM directional stations are more time-intensive and costly to maintain, especially when compared to FM stations.

On the positive side, I know a number of smaller AM/FM combination and stand-alone AM stations in Minnesota that are doing well. One town has a 1 kW AM with a 100 kW FM. The AM brings in 40% of the sales revenue because it has always been locally programmed with live announcers until 1 p.m., then is live again during afternoon drive.

AM radio isn’t supposed to sound bad. It can be a clean and pleasurable listening experience, even when there is only 3 kHz of audio bandwidth. On the other hand, AM can be ugly to the ear when there are maladjustments.

SCIENCE

Modulation is the process of adding audio to a transmitted signal. Amplitude modulation is aptly named. A station’s carrier (transmitter power) is varied by the station’s audio. Carrier power is depressed to zero watts to achieve 100% negative modulation. It increases to 1.5 times carrier power when 100% positive modulation is reached. That is why a thermocouple antenna ammeter reading rises with modulation. You read it during a programming pause to get an accurate measurement.

METERING

AM modulation monitors have –100% and +125% lights indicating overmodulation. You really don’t want those lights to come on. More is not better.

First, be sure to set the monitor’s RF carrier level control so the carrier meter needle is in the right spot, as per manufacturer’s instructions. A carrier meter misadjustment will result in inaccurate modulation monitor readings.

Fig. 1 shows an AM modulation monitor. The –100% and +125% lights are on and yet the analog modulation meter reads only 94%. It is normal for an analog meter to read lower than actual modulation. In fact, 85 to 90% is a more realistic meter display, because it cannot track peaks as lights do.

Fig. 1: AM modulation monitor showing overmodulation.

A monitor’s audio output will sound excessively bright or harsh if a de-emphasis audio circuit is not included. Monitors traditionally do not have this, but often a simple capacitor and resistor modification will do the trick. The idea is to undo the high-frequency boost that is a part of the audio processing, per the National Radio Systems Committee (NRSC) standard. As you probably know, the transmitted audio has increased high-frequency response to overcome high-frequency rolloff in most receivers. The goal is to restore flat frequency response to the listener. Some audio processor manufacturers are using non-standard pre-emphasis curves to suit their taste. That complicates getting a realistic feel for frequency response. At least they are trying to make the best of receiver frequency response roll-off.

ON A SCOPE

An article I wrote regarding the operation of oscilloscopes, “Your Scope Is a Tool for all Seasons,” appeared in the Jan. 13, 2013, edition of Radio World.

To refresh your memory, a scope has a display where a dot that travels from left to right is deflected up and down with voltage. In this case, we will look at a transmitter’s RF output.

Fig. 2: An AM RF carrier wave on an oscilloscope.

I’ll begin with Fig. 2. It shows an oscilloscope with a view of the transmitter’s carrier with the scope sweeping at high speed (0.2 microsends per horizontal screen division) to see the actual carrier wave of an AM radio station. By carrier, I mean the transmitter’s power output. What you see is an almost perfect sine wave at the station’s operating frequency.

 

Fig. 3: A carrier with no modulation.

Let’s zoom in to the scope’s screen. Fig. 3 shows the carrier when the oscilloscope is slowed down to view audio (0.2 milliseconds per division). No modulation was present at that instant. Fig. 4 shows a 1 kHz sine wave modulating the carrier 100% positive and negative. The positive parts are the top and bottom peaks. They are mirror images of each other. The negative modulation part is where the carrier is just pinched-off at zero power in the center of the screen. This sine wave is relatively clean/undistorted, with less than 0.5% audio harmonic distortion.

Fig. 4: A carrier modulated 100% with a 1 kHz sine wave.

Many receivers do not reproduce it that way. The last 5 or 10% of negative modulation, between 90 and 100%, is where receiver detectors have trouble faithfully reproducing what the transmitter is sending. The result is audio distortion. We all know that unwanted audio artifacts are a listener turnoff.

Fig. 5: 100% modulation with receiver detector output.

In Fig. 5, I’ve switched the oscilloscope to dual trace mode. It shows the transmitter at 100% modulation on the top trace. The bottom trace was sampled at the receiver’s detector. I made the measurement there so it rules out additional audio harmonic distortion, which might be added in the output stage. By definition, harmonic distortion is where this 1 kHz audio tone will have unwanted audio products at 2 kHz, 3 kHz, 4 kHz etc. because of non-linear system performance. In this case, distortion from transmitter through the receiver detector measured 5.1%. It was only 3.1% at 90% modulation.

Fig. 6: 125% positive modulation, 100% negative modulation with receiver detector.

Fig. 6: Traditional analog audio processing used diodes to clip the negative side of audio before it went to the transmitter so it would not attempt to overmodulate the negative modulation while allowing positive modulation to go to 125%. The downside is that it added as much as 6.5% harmonic distortion in the process. Add the receiver’s problems to the mix and you have a whopping 10.2% distortion. Ouch! You’d never allow that on FM.

Newer digital processors reduce but may not eliminate the problem. Yes, the station can be a bit (about 0.9 dB) louder on the dial, but it is irritating to many listeners. They don’t know how to describe it, but oops, there goes another tune-out! Again, some people hear it and some don’t. Best not to penalize the station with high modulation.

Fig. 7: The transmitter is being badly over-driven at 100% negative modulation.

Fig. 7 shows the transmitter being modulated at over 100% negative modulation. I’ve moved the scope’s trace up a bit so you can see detail. Negative peaks go flat to the center, which is no carrier at that instant. Modulation like this will not pass the required NRSC occupied bandwidth nor will it pass my ear test for listenability. It is tiring to hear.

Fig. 8 is where you want to be. No more than 95% negative modulation, the sweet spot between loudness and listenability.

Fig. 8: 95% program modulation of the carrier.

It is a shame to lose listeners for that last 5% (about 0.5 dB) of modulation. Few if any will hear the loudness difference. Likely most will hear grit in the audio of transmitters modulated to the max. You can make up much of the modulation percentage difference with careful adjustments of the audio processing, before it goes to the transmitter. Software-defined receivers eventually will solve much of this problem, but we need to deal with today’s radios.

When I was installing AM stereo years ago, negative modulation was usually set at 95% and positive modulation at 95% for stations to sound clean. It was positive +125% if the client preferred it. That extra positive modulation comes as “forced asymmetry” where the negative audio peaks are soft clipped so the positive peaks can go higher. Ouch!

Surprisingly, bad-sounding audio with less than 100% modulation will usually fit into the NRSC occupied bandwidth mask, in the FCC required annual measurement. That is because of the required 9.5 kHz low-pass filter in audio processing.

AM stations competed in loudness wars to beat the other guy years ago. Now it is time to give listeners a pleasant experience with natural-sounding audio. Don’t drive them away.

I grew up in a broadcasting family that owned two AM stations and no FM. Success was dependent on keeping listeners. Loudness was not the answer.

Comment on this or any article. Write to radioworld@futurenet.com.

Mark Persons, WØMH, is an SBE Certified Professional Broadcast Engineer. He recently retired after more than 40 years in business. His website is www.mwpersons.com.

The post Find Your Modulation Sweet Spot appeared first on Radio World.

The BBC has announced that its two flagship radio programs for Afghan audiences will now be carried live by Radio Television Afghanistan, the country’s national broadcaster.

BBC News Dari

“Majale Shamgahi,” which is broadcast in Dari, and “BBC Naray Da Wakht,” broadcast in Pashto, will have the first half of its hour-long evening news programs every day on RTA’s FM networks in all 34 provinces of Afghanistan, as well as on medium wave.

The BBC programs examine key local and international issues with daily reports, interviews and analysis.

“A partnership with the BBC further reinforces RTA’s mission of informing the Afghan nation,” said RTA Director General Ismail Miakhail.

Pictured from left to right are Diva Patang, RTA presenter based in London; Ismail Miakhail, RTA director general; Jamie Angus, BBC World Service director; and Ismael Saadat, planning and commissioning editor, BBC News Afghan.

“Adding BBC programming to our output will contribute to the provision of trusted and impartial news about Afghanistan and the wider world.”

[Read: Radio TechCon Opens Registration]

BBC News Pashto

“We are delighted that the new partnership with RTA will allow our content to reach more people in Afghanistan, on channels they already know,” added Jamie Angus, BBC World Service director.

Miakhail also said that the RTA Academy would use the BBC as an example as it looks to train its country’s journalists on ethical journalism.

“Majale Shamgahi” will air from 6:30–9:30 p.m. Kabul Time, and “BBC Naray Da Wakht” will air from 3–4 p.m. Kabul Time.

 

 

The post Radio Television Afghanistan Rebroadcasting BBC Radio Programs appeared first on Radio World.

Announces auction of FM broadcast construction permits and seeks comment on auction procedures

.

.

.

.

.

A Virginia licensee has been handed a $15,000 forfeiture — in addition to receiving a shortened license renewed term — after allegedly failing to keep proper issues and program files updated in the FCC OPIF database.

The Media Bureau at the Federal Communications Commission ruled in a combination order/notice of apparent liability that Seaview Communications, which is licensee of WPEX(FM) in Kenbridge, Va., apparently violated several sections of FCC rules.

[Read: AM Station Hit with $15,000 Forfeiture After Public File Lapse]

According to the bureau, the station allegedly failed to prepare its set of quarterly issues and programs lists and it failed to upload this information into the station’s online public inspection file. FCC Rules require that commercial broadcast radio stations place issues and program lists — which detail programs that he station has covered over a three-month period — every quarter . Those files must include a quick briefing of the issues addressed as well as lay out specific details such as the time, date, duration and title of each program. Stations must then upload certain public file documents to the FCC’s OPIF public inspection file database. As of March 1, 2018, all broadcast stations are now required to post public file info (except political file material).

When Seaview began the process of prepping its license renewal application, it answered “no” when asked if it has placed the required documentation into its public file. The station explained that it had difficulties in navigating the new on-line public inspection file. “As such, certain deadlines were not meet with respect to the ‘upload’ of issues/programs lists,” the licensee said, though Seaview said it had begun working with the FCC counsel and plans to resolve the public file upload problems.

However, this explanation does not excuse or nullify the violation, the bureau said. The commission has the authority to hand down a base forfeiture of $10,000 to those licensees who fail to maintain their public file and an additional $3,000 for failing to upload the required documentation.

The commission can also raise or lower those forfeitures based on the circumstances. In the case of WPEX, the FCC handed down a $15,000 forfeiture, saying that even though Seaview admitted to its violations, it did so only when compelled to answer via its renewal application. Moreover, the bureau found the violations were “extensive” and apparently encompassed the entire license term.

The Media Bureau also found that the licensee’s conduct fell short of the standard of compliance that the FCC uses when handing out a routine license renewal. “The issues and programs lists are a significant and representative indication that a licensee is providing substantial service to meet the needs and interests of its community,” the bureau said. As such, it concluded that a short-term license renewal of two years was warranted. “This limited renewal period will afford the commission an opportunity to review the station’s compliance with the [Communications Act] and the FCC’s rules and to take whatever corrective actions, if any, that may be warranted at that time.”

Seaview has 30 days to pay the forfeiture or respond seeking reduction or cancellation of the proposed forfeiture.

 

The post Virginia FM Handed $15,000 Forfeiture for Alleged Filing Violations appeared first on Radio World.

It’s time for broadcasters to confirm that their stations are up and running with the latest in EAS updates.

As it stands today, EAS participants are required to not only receive Common Alert Protocol messages from IPAWS but also configure their systems to reject all CAP-formatted EAS messages that include an invalid digital signature. Now, an effort to maintain compliance with commonly accepted security standards, FEMA is also taking the next step of removing support for older methods by requiring the use of an updated TLS 1.2 protocol to access FEMA’s IPAWS server, said Sage Alerting Systems and the Society of Broadcast Engineers. TLS, or Transport Layer Security, is cryptographic protocol providing communications security over networks and is often used for internet communications.

To acquire and verify IPAWS CAP alerts, a broadcaster’s EAS alerting equipment must be upgraded with the TLS 1.2 update prior to Nov. 8, 2019.

[Read: California LPFM Asked to Explain Alleged Transmission, EAS Violations]

The move is one of several rule changes put in place by the Federal Communications Commission and the Federal Emergency Management Agency to improve EAS security to ensure that messages are received smoothly and accurately.

According to Sage, the TLS 1.2 protocol is now part of a September 2019 update called Rev95. Certain ENDEC systems qualify for a free update; older systems will need to purchase an update via a distributor.

SBE cautioned in its blog that after the switchover on Nov. 8, older versions of the ENDEC software will not be able to receive CAP messages from IPAWS. “This will render the station in violation of FCC rules concerning EAS monitoring and logging,” the SBE said.

For Gorman-Redlich systems, the SBE reported that stations operating with E-prom V 9.5.8 will remain compliant with the changes. For Digital Alert Systems DASDEC/One-Net systems, those units operating with software versions 3.1 or 4.0 will remain compliant.

In addition to the CAP format changes, the SBE said the FCC also recently changed EAS rules to refine the time window within which an alert message is valid and added a new false EAS alert reporting rule.

 

The post Broadcasters Need to Keep Eye on Latest EAS Updates appeared first on Radio World.

WASHINGTON — Recent changes to certain FCC rules present opportunities for the industry to operate more efficiently, supporters believe.

Elimination of the main studio rule, the license posting requirement and the requirement to keep a hard copy of FCC rules at radio stations are three of the changes that have swept through the commission under the leadership of Chairman Ajit Pai.

Further significant regulatory amendments remain in the pipeline, such as the potential relaxation of local ownership rules, including modifying limits on common ownership of AM and FM stations in a market. Those decisions are pending completion of the FCC’s latest quadrennial review.

Further, the commission has launched a proceeding to simplify local public notice requirements for radio station applications, according to a FCC filing.

Radio broadcasters are focused  on adapting their operations to better compete in a more relaxed regulatory environment. “The deregulation of the past 18 months is significant,” said Scott Flick, partner at Pillsbury Winthrop Shaw Pittman LLP, ahead of a panel discussion of radio and financial experts at the Radio Show in Dallas.

“Early during Chairman Pai’s leadership he said he wanted to put one media deregulatory item on each month’s FCC agenda. They’ve hit a lot of the low-hanging fruit, but there is more to go,” Flick said. “I think we are on the brink of fundamental regulatory change.”

Radio broadcasters are researching alternate business practices to improve efficiencies, Flick said, but first they must consider structural changes in how they run their businesses.

“Radio broadcasters are so used to being micro-managed by the FCC that it takes a while for these changes to sink in. For instance, the elimination of the main studio rule. Of course broadcasters want to maintain a presence in their local communities, but there are circumstances where having a main studio, or at least what qualifies as a main studio now by the FCC, may not make sense anymore,” Flick said.

“Broadcasters are stepping back to ask how they might do things if they were starting from scratch today. They are giving their operations a fresh look.”

Flick said some of his broadcast clients are adopting new business strategies in light of deregulation, specifically the elimination of the main studio rule, but though not in large quantities. “It takes time to implement changes, and … leases are sometimes years long,” he said.

In addition, deregulation of any industry typically increases the interest level of investors, Flick said; he expects that to be the case for radio.

“Any time you cut out the regulatory straightjacket, then you have people asking, ‘Ok, now I might want to invest the money to figure out an alternate business plan,’” Flick said. “The risks are lower and the industry becomes less complicated with fewer government limits.”

Not everyone feels the direction of radio deregulation is a good thing, Flick said; and on some issues, radio companies don’t speak with one voice. For example, iHeartMedia and Urban One are opposed to a change in the ownership subcaps that many others support.

“Of course, there will always be a split on any proposed deregulation between those who feel the rule constrains them and those who like the rule’s constraining effect on their competitors,” Flick said.

Susan Patrick, co-owner of Legend Communications, said the regulatory environment is presenting opportunities to improve operations and in some cases expand them.

“We are fans of deregulation. It’s going to help small-market broadcasting and help us compete against all of the other audio services that are out there now,” Patrick said.

Legend Communications, which has 23 radio stations, including several FM translators across Wyoming, is always looking for business efficiencies, she said.

“We have several situations where the main studio rule being eliminated could help us. We haven’t made those changes yet. I have spoken to a number of small-market broadcasters who have combined studio facilities, and it has helped them use resources in a different manner that better serves their communities.”

Patrick, who is also co-owner and managing partner of brokerage firm Patrick Communications, said she does see the potential for some broadcasters to utilize the new rules to cut staffing by consolidating facilities.

“To say otherwise is naïve. Some people given the opportunity to save money will try to save money, while large operators are more likely to be able to afford to keep staff.”

Beth Neuhoff, president and CEO of Neuhoff Communications, said the deregulatory mode of the FCC can help radio broadcasters increase value in their properties.

“I think with deregulation there is tremendous upside to a disciplined operator and investor. One of the basic rules of economics is that mature industries must consolidate to survive,” Neuhoff said. “There is so much opportunity in the smaller market for a better, more efficient model.”

Neuhoff said regulatory moves by the FCC offer broadcasters relief but they don’t go far enough.

“I think there would be both top- and bottom-line growth opportunity with less regulation. The ability to streamline back-office and operations is certainly interesting,” Neuhoff said.

“The bigger opportunity in my estimation is top line. With greater scale, I believe markets like ours could be better served with more offerings both that serve multiple markets and a larger portfolio of digital.”

Those stations with market proximity “most certainly can and should take advantage of the main studio rule,” Neuhoff said, but the challenge will be keeping a local presence visible on the street.

Neuhoff Communications, which owns 20 radio stations, is reviewing its best business practices, she said.

“Interestingly enough, our Fast Forward team, our next generation of company leadership, is designing the station workplace of the future as their capstone project. They identified main studio as a real opportunity for us,” Neuhoff said.

David Santrella, president of broadcast media for Salem Media Group, said the broadcaster is looking upon the recent FCC dereg moves favorably.

“I think now all broadcasters need to run more efficiently. There are broadcasters always looking for ways to run their operations with less money than they did the year prior and the year before that. And so I think the main studio rule will present opportunities going forward,” Santrella said. “Salem will look at that.”

The FCC is simply allowing broadcasters to make changes to operations to better fit new technology, he said.

California-based Salem, with just over 100 radio stations in just under 40 markets offering Christian-centric content, is “not behind” the movement for a change in the subcaps, Santrella said.

“If they change the subcaps I think you’ll see more people abandoning the AM band and moving formats to FM. Such a move would devalue AM properties. We built a business based on the current model and regulations, so when you change the rules in a very long tail business, and radio is a long tail business, you severely impact the business model designed based on the rules as they exist,” Santrella said.

Santrella, who also chairs the NAB Radio Board, said radio will need to balance moves based on fewer regulations while not losing touch with radio’s greatest natural strength of being “a local community service” business.

What do you expect the impact of FCC rule changes to be on the U.S. radio business marketplace? Comment on this or any story. Email to radioworld@futurenet.com with “Letter to the Editor” in the subject field.

The post Radio Eyes Advantages of Deregulation appeared first on Radio World.

The author is chairman of Digital Radio Mondiale.

Is medium wave in decline? Some people think so.

In the 1950s radio was declared mortally wounded by TV. But then FM with its new music rescued it, becoming one of the most successful technologies and platforms ever. Radio survived and thrived but AM should have died at the hands of the nimbler, younger and more attractive FM.

Photo credit: Radu Obreja

Only it did not and the medium reinvented itself by using presenter-led programming, commercial music and sport. In the United States it took until the end of 1990s for the FM and AM audiences to be equal and to this day the big AM stations are going strong, bringing in the ad dollars.

REASONS

Still, it’s undeniable that the whiff of decline has enveloped AM in the past two decades. The reasons are well-known: Analog medium wave doesn’t always deliver the best sound, it can suffer from interference, it can behave annoyingly different by day and night and even by season. Medium wave mainly appeals to a maturing population (a global phenomenon, considered shameful by some!) using aging receivers (this is bad!).

Analog medium-wave broadcasting also needs quite an infrastructure and deep pockets for the electricity bill.

Ruxandra Obreja

On the other hand, medium wave is that middle sister that delivers by giving excellent regional coverage over hundreds or (overnight and if the ionosphere behaves) even thousands of kilometers, whereas FM goes up to roughly 200 kilometers and digital DAB+ to half of that.

Medium wave is not only a regional but also an excellent local coverage solution. In Australia 33% of the public broadcaster ABC’s local transmitters broadcast in AM and 11 50 kW transmitters are serving the mainland capital or big cities. Medium wave covers large areas and reaches small far-flung communities for whom, even in developed countries, medium wave and FM still provide the first source of information.

Besides, medium wave with its reach, availability outdoors and on the go, is a fallback solution in times of emergency or simply a good standby solution when other platforms or services are unavailable (broadband, satellite, 4G or the mythical 5G).

The listeners’ behavior and the demands of the digital world are such that tackling medium wave has elicited different responses from broadcasters and regulators worldwide. In Europe, where the frequency was much used and abused, broadcasters initially energized by the potential of IP have not thought twice about closing down many medium-wave transmitters. Some have survived the cull, for example, in the UK, France, Spain, or in some eastern European countries.

DIFFERENT SCENARIOS

Regulators in other parts of the world have embraced different scenarios. One was to migrate AM to FM, or AM to a digital solution for FM (HD or DAB+). This process has taken a long time and, despite some successes, has shown it’s no replacement for AM or for a full large regional or national coverage.

In other parts of the world, like Brazil, digital was not even part of the mix. The simple migration AM to FM is plodding on there, as this is easier done in smaller places than in bigger, overpopulated ones, like big cities where there is no FM spectrum available and where the original demand for a solution came from.

Another idea is to expand the FM band, downwards, migrate everyone and forget about AM altogether, as FM seems a proven and winning formula. A nice idea but then, on top of the costs of replacing a large area covering transmitter with many, expensive, spectrum and energy hungry FM transmitters, there is the extra challenge of the new receivers to be produced and actually sold.

Certainly, there is also the option of doing nothing. Reading through the most recent submissions to the judicious consultation launched by the Australian regulator on the future delivery of radio services, I was struck by how some contributors claim that there is no current replacement for analog AM. Their scenario is to leave things as they are, for at least the next 10 years.

[Read: Historic Woofferton Boasts a Modern Twist]

Change is though the name of the radio game. While analog AM will subsist, it is worth looking at other options, too. In India where most of the territory and population are covered by the public radio medium-wave transmitter infrastructure, the government and public broadcaster took the bull by the horns and deployed almost 40 digital transmitters covering about half the country population with a digital signal.

THE SOLUTION

Recently cricket fans were able to enjoy an open-air demonstration of three different DRM programs on one frequency ahead of an important match in Bangalore. The fans also received data (stock exchange values) available on radio screens. This demonstrated that digital DRM is a game changer for medium wave.

In DRM the crackling audio disappears as sound is as good of that on FM. The electricity consumption and costs decrease, the spectrum is trebled and reception, even in cars (as available in over 1.5 million cars in India currently) is excellent, too.

If it is so good then why isn’t DRM medium wave conquering the world faster? Maybe it’s about confidence in a new platform. Broadcasters and governments need to market DRM digital radio once signals are on air in their countries.

As for receiver availability and their costs, let us remember how many receivers were on sale in the 1970s when FM was taking over the world. Nowadays, many listeners consume radio in their cars rather than sit in front of a retro looking wooden box. Digital receivers (DRM alone or DRM/DAB+) are a reality and a bigger push for digital would help with volumes sold thus bringing down the prices.

Radio, and therefore medium wave, can and should survive digitally. Digital radio must be an enabler of audio content and information while preserving its ubiquitous and unmatched advantage of providing a service for all.

For that, a bit of imagination, trust and, last but not least, some long-term investment is necessary. Because medium wave is still worth it!

[Want more information like this? Subscribe to our newsletter and get it delivered right to your inbox.]

The post Solving the Medium-Wave Problem appeared first on Radio World.

.

.

Media Bureau issues its Second Report to Congress presenting the Commission's assessment of the current status of video description

.

.

.

.