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Industry News

Community Broadcaster: A Cautionary Tale

Radio World
5 years 6 months ago

The author is membership program director of the National Federation of Community Broadcasters. NFCB commentaries are featured regularly at www.radioworld.com.

This week’s big news in community radio was all about layoffs at Pacifica radio station WBAI(FM) in New York and termination of its existing programming. The seriousness of the situation is a bellwether to conversations community media must have about relevance.

WBAI is certainly an iconic noncommercial radio station. It has hosted a veritable who’s who of cultural vanguards, especially in the 1960s. From Bob Dylan to Malcolm X, WBAI has been fondly remembered by fans for such history. Unfortunately, those glory days are long gone.

When I wrote for Radio World about the Empire State Realty Trust $3 million judgment against WBAI and Pacifica in 2017, matters were already quite dire. Pacifica audits noted a listener support decline between 2007 and 2017 in the millions. The California Attorney General’s Office and the Corporation for Public Broadcasting Inspector General launched probes in 2015 and 2011 respectively over management issues. WBAI had seen crashes in 2009 and 2013, and its internal strife, inability to make payroll and subsidization by other Pacifica outlets had been in public circulation for years. WBAI folks, a smart and interesting bunch to be sure, have long contended what may seem to be farfetched theories, from essentially embezzlement by its licensee to its owner kneecapping the station staff and volunteers for their liberal orientation and willingness to host marginal programming under the free speech banner.

[Read: Community Broadcaster: Changemakers]

Indeed, any publication that termed this week’s action stunning or a shock clearly must be excused for not paying attention to a crisis decades in the making.

Pushback to Pacifica’s decision was swift, including a state court intervening in the situation. However, it may be unclear how influential a New York court injunction to prevent layoffs and program changes will be. After all, Pacifica is a California nonprofit organization. The network’s payroll and WBAI’s federally assigned license (and thus programming placed on it) are both based far from said court’s jurisdiction. This story is developing.

Regardless of what happens to WBAI, the health of community radio as a whole is always a concern. What can stations learn from this issue?

As I conveyed to radio station WORT this week, community radio stations should always ask themselves about how they are truly listening to and serving local listeners with content they are passionate about and rely on. It is not difficult to figure out why WBAI, at 99.5 FM and in a city of eight million people and with one of the nation’s top median household incomes, could muster only 78,500 weekly listeners (according to Nielsen Audio) and not cover basic expenses. An old friend at Radio Research Consortium, noncommercial media’s data clearinghouse, once shared, listeners tell you what they think of your programming with their ears and wallets. Every station should track what their local fans think, and be responsive to area needs. That can be hard, given the many perspectives that are part of a station, but centering listener experiences with our stations must always be a priority.

Careful financial monitoring and adopting an approach to problems that sees them as a shared responsibility should also be a part of any station’s ethos. When tensions arise, the easy way out is to cast blame on others. Difficulties such as those experienced by the community radio space this week might have been averted with more swift, productive actions, and buy-in from everyone. All community stations might be wise to unify in times like these.

And finally, every station would be well served to take the lead in telling its story. In times of trouble, explaining one’s vision and where one hopes to be reassures listeners and tells donors you have a solution. Once a station loses control of its narrative, it is hard to regain credibility. Pacifica’s message posted on WBAI’s website is a start, in this instance.

Noncommercial radio observers may recall the WBAI move is not without precedent. In May, Humboldt State University shuttered its volunteer-based programming and laid off staff at KHSU in a bid to reorganize. A Humboldt State University advisory review identified a need for financial review of university investments, a realignment of the station’s operations and other issues for the licensee. One can hope WBAI’s reorganization is successful, and that all of community radio takes a cue from what’s happened to make the best media possible.

 

The post Community Broadcaster: A Cautionary Tale appeared first on Radio World.

Ernesto Aguilar

Does 5G Make Sense for Radio?

Radio World
5 years 6 months ago

The author is the head of technical and infrastructure department at German national public broadcaster Deutschlandradio.

The reception of radio programs with smartphones is becoming increasingly important for radio makers, particularly due to young people’s tendency to use their hand-held devices for a wide range of purposes — information and entertainment, social media networks, smart home and smart speakers, amongst others.

Chris Weck

There is no doubt that broadcasters have to be present on that platform with both linear and non-linear audio, with social media and the various functions of the internet.

At first glance, 5G broadcasts seem to be a promising solution for the future of broadcasting, and a viable solution to bring radio to the smartphone — one device and one transmission standard on one transmitter network. But who will benefit from this — the user, the mobile network operators, radio broadcasters or the industry as a whole?

Physical laws for radio communication are still valid for 5G as for DAB and all the other broadcasting and telecommunication schemes. From the well-known Shannon limit of 1948 we know that a minimum of energy per bit is necessary in order to provide an error-free transmission over a channel with a certain bandwidth (Eb/N0 = −1.6 dB in AWGN-Channel).

New and very efficient transmission systems like 5G are able to transmit very high data rates in a channel of a certain bandwidth, however, the energy per bit will never fall under the minimum defined by the Shannon law. With other words, the higher the data rate of a transmission system, the higher the signal-to-noise ratio required. This means in practice for a certain transmitting power the size of the transmitter cell will be reduced for higher data rates accordingly.

Now, from a theoretical point of view with respect to the energy per transmitted useful bit (including all the overhead), there is no significant difference in performance between 5G modulation schemes compared to the still very robust system of DAB+.

The 5G broadcast mode provides also a robust QPSK modulation to make use of bigger cell sizes. However, the expected performance compared to DAB especially in a single frequency network is rather the same. In fact, there are no results of a system comparison in the field available and therefore it is reasonable to focus on other basic differences between the idea of 5G broadcast and conventional DAB+ broadcasting.

Today, DAB radio receivers have an external antenna as well as car receivers. In comparison to a smartphone with a less sensitive built-in antenna, the link budget for the required field strength differs at minimum of 15 dB or even 20 dB and more.

This means that in order to achieve the same coverage for radio reception by smartphones, 10 dB more transmitting power is required. This is also true for 5G broadcast networks, so that 5G broadcast networks for smartphone reception have to aim for 10 dB more transmitting power compared to a conventional DAB+ network. In practice, this means that a significantly denser transmitter network is required for 5G broadcast to smartphones than for conventional DAB+.

Radio reception differs for smartphones compared to conventional radio receivers.  The field strength required depends on the effective antenna size, and has to be higher for smartphone reception.

The reduction of the transmitter distance can be anticipated easily from the CCIR propagation curves. For example for VHF propagation a loss of field strength of 20 dB corresponds to a reduction of the distance to the transmitter from 30 km to 10 km.

With the basic transmitter distance of about 60 km for DAB+ networks, the average transmitter distance for 5G broadcasting to smartphones has to be around 20 km. In fact this means that the transmitter distance has to be reduced by a factor of three in order to overcome a loss of 20-dB field strength. This means nine times more transmitters in the area are required in order to achieve the same coverage as a conventionally planned DAB+ network. Can radio broadcasters really afford this? In fact round about 10 dB more transmitting power results in 10 dB more money.

For the time being, the national DAB multiplex in Germany comprises of 130 transmitters in a nationwide SFN. Today, coverage stands at around 95% for mobile reception, but in order to reach 99% coverage, the number of transmitters has to be increased to 250 at least and may be around 400 (including small gap fillers) in the long term.

With 5G Broadcast round about 10 times more transmitters will be required which might sum up to 2,500 or even 4,000 transmitters in Germany. The mobile network in Germany comprises already 40,000 transmitters today and everybody experiences that this is rather not enough. Concerning 5G mobile networks, experts anticipate that future high data rate networks will be based on a cell size of less than 1 square kilometre, which would sum-up to around 400,000 transmitters in Germany for nationwide area coverage.

CCIR 370 Propagation Curves

What can we learn from these facts?

  1. The DAB+ network with its low number of transmitters is the most efficient network to realize a full area coverage
  2. The 5G broadcast networks, the mobile network and future 5G mobile networks require far too much transmitters for a full area coverage that nobody can expect the same area coverage as for DAB radio services

Assume e.g. transmitting costs for a full area DAB network in Germany of about €25 million per year. In order to gain 10 dB more transmitting power for smartphone reception, the network will cost a nationwide broadcaster approximately €250 million per year, as opposed to €25 million a year for conventional DAB. In Germany, no broadcaster is in a position to afford this amount of money — the price for this purpose to reach smartphones with radio is incredible high, and quite frankly, out of reach for any public broadcaster.

If one says that 5G would only be applied in cities as opposed to rural areas, the additional costs would indeed be lower. However, setting aside a budget of €10 million a year for this purpose is also unrealistic for a broadcaster and, should this sum even be available, it would certainly make more sense to spend it on the DAB network, where coverage gaps could be closed, and where broadcasters and consumers could benefit from it.

What’s more, it wouldn’t make sense for a broadcaster to give up nationwide DAB coverage. In order to supply 10% of the area with 5G broadcast to mobile phones for the same amount of money.

So, if broadcasters are far from being able to afford 5G broadcasting, who would pay for this? Mobile network operators will never provide a 5G-radio service for free, and broadcasters will not pay for 5G broadcasting either, so there really is no business model for either.

The one and only solution is that the user pays for the broadcasting service to his smartphone — this could be done by a contract with the broadcaster or with the mobile network operator, something that is already being done today with 3G/4G.

The smartphone user has a mobile contract and pays for the data volume on an individual basis. This enables the mobile network operator to set up very dense mobile networks that have enough power to be received by small smartphones. This works perfectly for radio with LTE and even UMTS, so why wait for 5G broadcasts?

Users already have radio services available on smartphones today, and it works well, so long as the user has enough high-speed volume on his contract.

Today, hybrid radio with DAB+ and Internet via mobile networks or via Wi-Fi at home provides the most suitable solution. Hybrid radio is the perfect fit for all broadcaster and user requirements, as with DAB+ it allows broadcasters the proven and most efficient radio network at an affordable price for area-wide coverage. It allows for free access of the users to radio and information, regardless of whether they live in cities or in rural areas, and whether or not they can afford a high-volume data contract for their mobile phones.

Hybrid DAB radio provides broadcasters with a content distribution platform directly linked to the customers, and independent of the commercially driven infrastructure of mobile network operators. This may be an advantage for emergency warnings, too.

On the other hand, users already have audio streaming and additional non-linear services available on their smartphone via the Internet. So, the only need for radio broadcasters today is to think about attractive hybrid radio services, and an impactful marketing strategy for their brand.

I cannot comprehend why broadcasters and politicians would want to switch a system running with DAB and IP with the more expensive, and in practical terms less efficient system that is 5G. Instead, why not use and extend the existing and approved technology? Hybrid radio is the best approach both economically and in terms of efficiency, and this is unlikely to change in the future.

Diversity between broadcaster networks and mobile phone networks will result in better efficiency and will offer more advantages than disadvantages for broadcasters as well as for users — so proceed with Hybrid DAB and IP. There is no need for 5G for radio broadcast.

[Read: Using Digital Radio to Boost Listening Figures and Revenues]

 

The post Does 5G Make Sense for Radio? appeared first on Radio World.

Chris Weck

Radiodays Europe Announces First Group of Speakers

Radio World
5 years 6 months ago

Six industry professionals have already made their plans to attend the 2020 edition of Radiodays Europe in Lisbon, Portugal, as the conference has announced the first batch of its planned speakers.

Those confirmed to speak at next year’s conference are Cilla Benkö, director general and CEO for Swedish Radio; Cathrine Gyldensted, co-founder and director at the Constructive Journalism Network in the Netherlands; Yagmur Özberkan, journalist and presenter for YLE, Finland; Torben Brandt, Danish radio legend; Ole Hedemann, content developer and head of formats at NRK in Norway; and Susani Mahadura, journalist for YLE, Finland.

Radiodays Europe Lisbon 2020 is going to take place from March 29–31, 2020. For more information or to register for the event, click here.

 

 

The post Radiodays Europe Announces First Group of Speakers appeared first on Radio World.

RW Staff

“THAT Thing” — A Solid-State Mic Preamp Project

Radio World
5 years 6 months ago

Over the years I’ve become a student of mic preamp design, building and modifying several along the way and learning a little more each time. Usually, I worked from a kit or published set of plans. Recently, I’ve tried some designs from “scratch,” researching various components, studying earlier designs, and incorporating them into raw schematics, followed by circuit layout, design tweaks and final fabrication.

Since my last two builds were vacuum tube devices, I wanted to do a simple, solid-state design this time. I came across some old preamp ICs in a parts box and almost used them but discovered they had been obsolete for years.

Was there a viable updated replacement? Enter THAT Corp., a relatively small IC manufacturer that specializes in chips for audio applications. THAT makes a few chips that are direct replacements of some popular preamp ICs like the Analog Devices SSM2019 or Texas Instruments INA163. If you’ve ever cracked open a broadcast console, you may have seen one. THAT’s website is a treasure trove of design notes and white papers on mic preamp design, with plenty of ideas to get a project going.

This project uses two ICs from THAT: the 1512 Low-Noise Audio Preamp, and the 1646 Balanced Line Driver. Using design notes from THAT and other sources, including advice from several more experienced DIYers, I was able to come up with a relatively low-cost design that has plenty of gain and good performance numbers for most applications.

The mic preamp can make or break a recording. Aside from the microphone, it’s the first stage in the signal chain before the recorder, and in some cases the only stage. It has to be clean and have ample headroom (unless noise and distortion are your thing), yet have sufficient gain to handle a wide variety of microphones.

Professional microphones have a balanced output, so the preamp will have a balanced input. Normally this is accomplished either with transformer balancing, which is expensive, or by using a standard op-amp as a differential amplifier, usually involving two op-amp stages with their attendant gain feedback loops, etc. The THAT 1512 takes care of this within the chip, providing its own balanced input. All that’s needed is a pretty standard input stage that can provide phantom power. The phantom power is sent to Pins 2 and 3 of the input XLR jack through a matched pair of 6.81K resistors, R1 and R2. These limit the current of the phantom supply.

The phantom power section

In order to preserve common mode noise rejection, any components that are mirrored between positive and negative signal paths must be matched in value as closely as possible. SW1 [switch] allows for turning off phantom power when it is not needed, and LED1 illuminates to show the actual presence of phantom voltage. R9 limits current through the LED to keep it from going “poof!” Capacitor C13 is there to smooth out any ripples from the 48 V supply. Between Pins 2 and 3 of the input jack and ground, ceramic capacitors C1 and C2 shunt any RF noise that might hitch a ride on the mic cable. Bad mic cables make good radio antennas!

Keeping stray static at bay is the job of the diodes.

Obviously, we need to keep 48 VDC out of our audio circuit. In a transformer-based design, the transformer would handle this, as transformers only pass AC. Likewise with capacitors, which are much cheaper and take up less space. This is why inexpensive designs use them. The problem is that inexpensive designs tend to skimp on these coupling capacitors. Years ago, I hot-rodded a mic preamp that originally had 4.7µF tantalum capacitors in the coupling stage. I replaced them with nonpolar electrolytics of a much higher value, and performance was improved.

Here, for C3 and C4, I use the same ones. At 100µF it’s overkill, I’ll freely admit, but the higher value reduces low-frequency phase shift (the LF response here is in the single-digit Hz range). Anything around 22µF or greater will work. Besides, it’s very difficult to match capacitors to such tight tolerances.

The high-pass filter is engaged by a switch — SW2.

Here’s where R5, R6, and R7 come in. They form what THAT calls a “T-bias” circuit, which boosts low-frequency common mode impedance. C14 is another ceramic capacitor across the inputs to clean up any remaining RF noise. By the way, R3 and R4 are there to limit any fault currents that might sneak by the capacitors. Their low value prevents input impedance issues.

Additional protection from stray static charges and other voltage transients is provided by diodes D1 through D4. This is a simplified version of a number of protection circuits I’ve seen. Anything ugly gets shunted to ground.

Now, it’s on to the preamp IC, which does the heavy lifting in terms of gain: up to 60 dB of gain, in fact. While a lot of designs will set the chip at a fixed gain level and introduce level controls somewhere between subsequent stages, ours is a simple mic preamp. It would be a simple matter of just inserting a potentiometer (VR1) across the gain setting pins of the chip, right? Not that easy!

Rapid changes in that resistance can introduce DC offset in the chip, which translates to thumping and popping on the output. This is where C5 comes in; a very large capacitor to kill DC offset. Why so large? Because VR1, R8, and C5 comprise a high-pass filter, so the capacitance has to be large enough to bring the low-frequency response down. In this case, it puts it around 5 Hz at maximum gain, keeping any rolloff well below 20 Hz. VR1 is a reverse-log pot, which provides the correct gain vs. position curve.

Capacitors C7 through C10 filter RF gunk out of the power rails to each chip.

Speaking of high-pass filters, I included one here to roll-off any mic or room rumble. C6 and SW2 provide a HPF, but this one has a twist. (Special thanks to the folks at www.groupdiy.com for this idea.) Because the changing resistance of VR1 naturally changes the characteristics of the HPF, this filter’s rolloff actually increases somewhat at higher gain settings. At first, this may seem undesirable, but think about it — low frequency artifacts are more likely to be a problem at higher gains than at lower gains. At any rate, C6 is small enough to rolloff the low end, but not to the point of sounding thin.

Now on to the output stage, handled by the THAT 1646. It’s one of the simplest I’ve ever seen. One IC and a couple of nonpolar capacitors. Caution must be used if inserting any other stages or components before the 1646, as it is very sensitive with regard to impedance. C11 and C12 are there to address any common-mode DC offset on the outputs. From there, it’s on to the output XLR jack, passing through a simple polarity switch, SW3, to reverse phase if needed.

Finally, capacitors C7 through C10 filter RF gunk out of the power rails to each chip, a very important consideration in any design. Clean audio has to have clean power.

Since this whole thing is built around THAT ICs, I decided to simply call it “THAT Thing.” Tune in next time, and we’ll talk about the power supply, breadboarding the prototype, and putting it all together.

More information about the THAT 1512 and 1646 ICs, as well as design notes and other information can be found at:

• www.thatcorp.com/Design_Notes.shtml
• www.thatcorp.com/datashts/THAT_1510-1512_Datasheet.pdf
• www.thatcorp.com/datashts/THAT_1606-1646_Datasheet.pdf

Curt Yengst, CSRE, is a contributor to Radio World and an assistant engineer with WAWZ(FM) in Zarephath, N.J.

Email us with your own DIY ideas at radioworld@futurenet.com.

The post “THAT Thing” — A Solid-State Mic Preamp Project appeared first on Radio World.

Curt Yengst

Find Your Modulation Sweet Spot

Radio World
5 years 6 months ago

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.

Mark Persons

Radio Television Afghanistan Rebroadcasting BBC Radio Programs

Radio World
5 years 6 months ago

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.

RW Staff

Virginia FM Handed $15,000 Forfeiture for Alleged Filing Violations

Radio World
5 years 6 months ago

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.

Susan Ashworth

Broadcasters Need to Keep Eye on Latest EAS Updates

Radio World
5 years 6 months ago

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.

Susan Ashworth

Radio Eyes Advantages of Deregulation

Radio World
5 years 6 months ago

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.

Randy J. Stine

Solving the Medium-Wave Problem

Radio World
5 years 6 months ago

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!

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

Ruxandra Obreja

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