2013 NAB: IP Codecs, Transmitters,
the Future of AM and other Cool Stuff

| April 11, 2013

By Thomas R. Ray, III CPBE, AMD, DRB
Tom Ray Consulting
President
TALKERS
Technical Editor

NEW YORK — Greetings from 29,000 feet over Colorado.  I’m returning from the NAB Show in Vegas and there were some very interesting items to see this year.  I am going to wait until next week so I can put together a good article regarding IP codecs, so please stay tuned for that.  I moderated a session in the Broadcast Engineering Conference on Sunday, April 7, called “IP for Radio”.  A lot of good information came out of that session – I need to go back and review my notes.

First, the IP codecs

And speaking of IP codecs – just about everything I saw at NAB was IP, IP, IP.  Since nearly everything is microprocessor based and IP connected, there are some interesting things you can do.

For instance – Nautel was running one of their FM transmitters – that was running an ENCO automation system.  Without the separate computer to run ENCO.  Consider what this could mean for your station.  If your station runs strictly automated, you literally have the radio station in a box.  It is possible to interface audio switching and GPIO capability and run a satellite-delivered format right on the transmitter.  Or a music format.  Or, if you were to lose your STL link, the transmitter would have built in capacity for backup audio to keep the station on the air.

Console manufacturer Logitek had one of their consoles also running the ENCO automation system.  No extra computer for the ENCO operation.   Doing this would allow for more compact studios and less heat generation in the studio.  I asked what would happen if the ENCO “computer” were to lock up.  Of course, if your station were running a music format, you would most likely be off the air at this point, unless you had someone available to pop on a CD.  But the console itself would most likely keep operating.  So there are considerations to putting all the eggs in one basket – but these considerations are getting less worrisome as technology progresses.

Another innovation, shown by Nautel in cooperation with Omnia Audio, was a direct digital link for the composite stereo signal required for analog FM stereo operation.  The Audio Engineering Society (AES) is completing work on a new standard for digital audio that will allow a signal with the bandwidth of the FM stereo composite baseband to pass digitally.  Currently, you can bring your audio all the way to and through the audio processing in the digital domain – but it needs to be converted back to analog for the stereo generation process.  It is then reconverted to digital when connected to the exciter to modulate the carrier, as most exciters are digital in nature.  The new AES standard allows this connection of the composite baseband signal to remain in the digital domain – meaning that your audio will remain completely digital into the transmitter.  There is a definite audible difference when the double conversion is removed and is well worth the consideration.  At the moment, Nautel transmitters and the Omnia 11 processor support this AES standard.

Transmitters

On the transmitter front, the trend is more in less space, at least for FM.  Harris has eliminated their “Z” line of FM transmitters in favor of the Flexiva series.  Flexiva transmitters were introduced a few years ago and are essentially smaller, more compact versions of the venerable “Z” series of FM transmitters.  The new Flexiva can put 20,000 watts into one rack freeing up space in the transmitter site.

For digital audio delivery and automation systems, the usual “big guys,” among them, ENCO, RCS, and Prophet/Next Gen were showing their tried and true systems.  But what if you have a small station – and a small budget – and can’t really afford to go with the big boys?  I bumped into an old friend I had lost track of – and he is with Ron Paley’s Digital Jukebox.  They have quite the system for an extremely reasonable price.  Sure, you won’t get some of the bells and whistles that the big boys offer – but for mid-size to smaller stations in mid-size to smaller markets, the system is well worth looking at.

The future of AM

Of course, as you have read here over the past few days, AM revitalization was a key topic of the show this year.  Many topics were brought up.  Yes – some require money to accomplish, like going digital.  But some missed the point – that the AM band and AM stations are still viable in the industry.  For far too long now, AM stations and their needs have been ignored.  Many have announced the “death” of AM.  And there are many reasons for this – and, at times, we broadcasters are our own worst enemies.

First and foremost, we have allowed, or shall I say, we have settled for the receiver manufacturers putting together AM radios that simply – sound – bad.  The typical audio bandwidth of an AM receiver is the equivalent – or less – than that of a telephone call.  The distortion is horrendous.  It’s no wonder the public perception of AM is less than stellar.  While you cannot change the laws of physics, there are many ways that digital signal processing could be used to make better AM radio sections.  We need better AM radios out there because we can and do transmit AM signals that are well worth listening to.

But, back to my statement that we broadcasters are our own worst enemies…  There are far too many AM stations running 20+ year old transmitters and 20+ year old audio processing.  Very frankly, what reason have we given the receiver manufacturers to make better AM radios when we are putting out sub-par signals in many cases?  Yes, I realize this costs money.  But how can we expect to remain competitive when, in some cases, we are using technology that has been past its prime for far too long?

When was the last time you took a trip out to the transmitter site?  And I’m not addressing the engineers reading this.  I have been to many an AM facility where I could not get out to the bottom of the towers because of the overgrowth of the tower field.  The towers are rusting – badly.  There is an infestation of vermin in the building.  This is not necessarily the fault of the engineer taking care of the site.  If he is not given the time and resources to do the job correctly, this is what happens.  Vegetation in the field absorbs signal and destroys the ground system which is necessary to maintain the efficiency of the antenna system.  Rusting towers decrease the efficiency of the radiating element (the tower), and destroys the structural integrity of the tower – not to mention making it an eyesore.  Vermin in the building?  That will destroy your equipment.

If we ran trucking companies and did not change the oil in the engines in our trucks – did not wash the corrosive splatter from the roads off our vehicles once in a while – did not repair the trucks as needed, what would happen?  We would not be able to reliably deliver the goods our customers were counting on us to deliver.  We would lose revenue, and eventually we would be out of business.

Our transmitter and studio facilities are our delivery systems.  And in many cases, we are allowing them to deteriorate – then blaming everyone but ourselves for our woes.

I am not a programmer.  But I will dare say that in many cases, we also do not provide any reason for the listening public to put us on.  I am involved with an internet TV program called This Week in Radio Tech (TWiRT), and we have said time and again it is all about content, content, content.  Give a person a reason to tune in, they will.

AM revitalization begins with all of us.  It’s not just a technical issue, but that is a big part of it.  We need to start paying attention to our AM stations, correcting the technical neglect of the past 10-15 years – and yes, if we have let the facilities “go to pot,” if you will, it would run into a considerable chunk of change to correct.  We need to start programming the stations with programming that will attract the listeners.  And we need to demand better AM radios.  It will take time and a commitment from every part of the industry, but AM is far from dead.  And we can keep it alive.  I can’t wait for the debate to really get going with this one.

Other cool stuff

On a final note, television gets my nod for the coolest products shown this year at NAB – helicopter cameras.  They had small versions, and one that was 8 feet long that would support a full HD payload.  All were remote controlled similar to an RC vehicle.  And they were the coolest things to see flying around.

And Telos gets my nod for coolest “swag” at the show.  I had to be very careful not to drop an “F” bomb on the show floor – because Telos was giving away those little stress squeeze balls shaped like a bomb – with the letter “F” on it.  Everyone I showed it to wanted one.  So yes, I had some fun, too.

Points to ponder while our industry goes through its latest series of changes.  Next week, we revisit IP codecs and the demise of ISDN.  You may not like – and you may be surprised – at what I present.

 tbugk

Thomas R. Ray, III CPBE, AMD, DRB is president of Tom Ray Consulting and Technical Editor of TALKERS. He can be phoned at 845-418-5065 or emailed at tomray@tomrayconsulting.com.  His website is www.tomrayconsulting.com.  Meet Tom Ray at TALKERS New York 2013 on Thursday June 6.  

 

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Category: Technical