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Blog Central

IP Radios and SIP with Bob Newberry

Posted by Kirk Harnack [TWiRT] on Jun 30, 2014 10:07:00 AM

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TWiRT 218Bob Newberry at Clear Channel in Birmingham, Alabama, oversees engineering at 11 radio stations plus 4 HD signals.  Pushing the technology envelope means using new IP-radio technologies along with IP telephone systems - and both areas give Bob more options, better quality audio, and some money savings, too.  Joe Talbot from Telos joins me talking with Bob about learning SIP technology while putting it to good use.




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Kirk Harnack: This Week in Radio Tech, Episode 218, is brought to you by Lawo, maker of the new crystalCLEAR virtual radio console. It's the radio console with a multi-touch touchscreen interface.

And by the Telos Z/IP ONE IP audio codec. Telos is the best way to hear from there.

Hey, Bob Newberry at Clear Channel in Birmingham, Alabama oversees engineering at 11 radio stations, plus four HD signals. Pushing the technology envelope means using new IP radio technologies, along with IP telephone systems. And both areas give Bob more options, better quality audio, and some money savings, too.

Joe Talbot from Telos joins me talking with Bob about learning Z/IP technology while putting it to good use.

Hey, welcome in, and thanks for joining us. This is This Week in Radio Tech. It's the weekly show where we get together with some engineers in the radio biz and talk about what's going on. Talk about the jobs that we do. Talk about how to take care of equipment, how to fix equipment. Share some ideas on making the broadcast plant work better.

You know, radio broadcasting is just such still a huge industry across the country. Thirteen thousand radio stations in the US. Something like 45 or 50,000 stations around the world.

So, hey, we've got a big audience of engineers, and folks who want to be engineers. Maybe program directors and talent who like to understand what the engineer is doing and how to put new concepts to use. So that's what the show's about.

Our show is brought to you by two terrific sponsors. The folks at Lawo, L-A-W-O, Lawo. They make the crystalCLEAR virtual radio console. We'll be talking about that in a little bit.

And also brought to you by the Telos Alliance. And this week, our sponsor is the Telos Z/IP ONE IP audio codec. I might even try to do a little demo on here before we get done with the show.

All right. That's the ifs, ands, or wherefores. Let's bring in our co- host. He's here every once in a while. And great guy. He's the telephony guru. It's Joe Talbot from the high desert in somewhere near Area 51. Hey, Joe. How are you?

Joe Talbot: Very close. Hi there. I'm doing well. How are you?

Kirk Harnack: I'm great. I'm great. It's good to see you. I see you've got your office cleaned up.

Joe Talbot: I had to do that right before you told me about the show, so I moved all the papers out of view. You can't see them. Just being honest.

Kirk Harnack: Well, actually, hey, I'm not giving away . . . talking out of school if I say that Joe bought a really interesting house near Area 51.

Joe Talbot: It's a fixer.

Kirk Harnack: It was a fixer-upper. But you got a great deal, buddy. You really did.

Joe Talbot: Crazy house.

Kirk Harnack: I think you could hold the next Telos corporate meeting out there.

Joe Talbot: We've been talking about it.

Kirk Harnack: And I understand you just got the pool. The pool's good and warm now for swimming?

Joe Talbot: It's beautiful. It's just beautiful. Yeah.

Kirk Harnack: You're . . .

Joe Talbot: In fact, I've been working on a little pump house for it. So that's my non-technical project here the last few weeks.

Kirk Harnack: Very nice. Very nice. Well, Joe, we're glad to have you along.

And, Joe, I thought of asking you on the show at the last minute. So, hey, thanks for shoving stuff aside and being with us for an hour here.

Joe Talbot: Sure.

Kirk Harnack: However long you can stay.

Let's bring in our guest. Our guest . . . I've been waiting to talk to this guy on our show for a long time. It's my friend I met ten years ago when I was showing off some Omnia audio processing. It's Bob Newberry.

Bob, welcome in. You are the director of engineering for the Clear Channel cluster in Birmingham, plus a couple of other bedrooms.

Bob Newberry: That's right. Yeah. Tuscaloosa and Gadsden. Birmingham. Sixty miles one way, sixty miles the other. And we're in the middle.

Kirk Harnack: Well, Bob, I think maybe you and I have both aged a bit since the last time we talked.

Bob Newberry: Oh, yeah, I know I have. By the way, it's my birthday today.

Kirk Harnack: Really? Well, happy birthday.

Joe Talbot: Yeah, happy birthday.

Bob Newberry: Well, thank you.

Kirk Harnack: I think we'll probably hold off singing, because we do want to keep the audience through the whole show.

Bob Newberry: Definitely don't want to use candles at this age.

Kirk Harnack: I hope you have a great birthday. So thanks for letting us know about that. Thanks for joining us on this special day. I thought you'd be taking the day off.

Bob Newberry: Oh, no. Never.

Kirk Harnack: So let's . . . we're going to get into some ideas about SIP telephony. And that's been a hot topic among broadcast engineers. You know, the whole business community has been moving into SIP telephony for years now, and broadcast engineers are a little slower to take it up, partly because the equipment to do it, to put callers on the air via SIP telephony, that has just been coming online in . . . well, I guess the Telos VX system has been around for about three years. So only the last three years has SIP telephony been convenient to put on the air.

So we're going to go there. We're going to talk about that in a few minutes. And I want you just to stay tuned for that.

Bob, I thought we'd open the show and just chat for a few minutes about broadcast engineering, radio engineering, like you do, for a big cluster, in a city like Birmingham, Alabama. What's going on in Birmingham, and what's on your weekly horizon here in terms of engineering issues and things to solve?

Bob Newberry: Well, most everything we do has . . . you know, most of our problems revolve around air conditioning and generators, emergency generators, more than the transmitters. The transmitter plants are fairly stable. It's all the support equipment that usually goes south a lot.

Kirk Harnack: Oh, that's right.

Bob Newberry: But I've got eight FM stations in three markets, three AMs, three translators, and four HD stations we're running.

Kirk Harnack: Wow. Okay.

Bob Newberry: Mostly out of Birmingham. We have studios in Tuscaloosa and Gadsden, like I said. And that's also been my test bed, so to speak, for our SIP phone systems.

Kirk Harnack: Oh, yeah. Okay.

Bob Newberry: I can have a breakdown a little easier over there than I can here in Birmingham.

Kirk Harnack: We'll talk about that.

Bob Newberry: But we use . . . did you want to get into that later?

Kirk Harnack: Oh, I don't want to put it off for a long time. I just kind of wanted to get a feel for what your life is like engineering in a big southern city, Birmingham. You know, an old city. Used to be -- actually, folks may not know this -- a big iron-producing city, because of the iron mines that you've got around Birmingham.

Bob Newberry: Oh, yeah.

Kirk Harnack: Tell us what the market is like. What market size are you in?

Bob Newberry: It's all about health now. They've shed that blue collar image and gone with medicine. And if you're going to get sick, Birmingham would be the place to do it now.

But I don't know. What is our market size? I should know that. But I want to say it's around 70, or high 60s. I don't know. Just outside the top 50.

Kirk Harnack: Got you.

Bob Newberry: But . . . well, I lost my train of thought.

Kirk Harnack: Birmingham . . . I'm looking at Birmingham radio market sizes. I'm really . . . it seems like a big city whenever I visit you guys. Whenever I . . .

Bob Newberry: I don't think it's . . . what's Nashville?

Kirk Harnack: Nashville, for radio, is about 44 or so.

Bob Newberry: Yeah. I think we're right outside the top 50. See, I should have my program director in here. But I really let him do all that.

Kirk Harnack: You're right. Birmingham's number . . .

Bob Newberry: I've got one assistant, a very capable man, Richard Spavins, and I've got a great IT guy, and he keeps me out of trouble most of the time, or backs me out of the trouble I usually get into.

Kirk Harnack: You know . . .

Bob Newberry: That's Ed Hyde. So both of those guys together and I just kind of run these three markets. And it's quite a challenge sometimes, because the weather moves from west to east. Tuscaloosa's to the west, Gadsden to the east. So if we have troubles, that's the way it usually rolls. And somebody has to roll one direction, and I'll roll the other direction.

Kirk Harnack: You've got a . . .

Bob Newberry: But, you know, a good night, we can get through it.

Kirk Harnack: You guys occasionally get some really wicked weather there.

Bob Newberry: Bad weather, yeah.

Kirk Harnack: My friend, a guest on this show, James Spann, has .

Bob Newberry: Yeah.

Kirk Harnack: . . . done a lot of tornado coverage, play-by-play. He was a guest on the show here a few years ago. You guys get some wicked weather. But Tuscaloosa tends to get it first, before it moves into Birmingham?

Bob Newberry: They get it first, right. Yeah, we lost a tower about three years ago during that tornado through there. And then Birmingham, we didn't do too bad. But, yeah, we have our challenges with the weather.

Kirk Harnack: Do you have any towers on mountains around there? Because it is a bit mountainous around Birmingham.

Bob Newberry: In Birmingham, yeah. Most of TV and radio is right on Red Mountain, and that's where our studios are, too. About a mile from one tower and about four miles from another one of our towers. Our main tower is what we call Eschuda.

Kirk Harnack: Eschuda. That's right.

Bob Newberry: Where we've got [inaudible 00:08:52] on it.

Kirk Harnack: I should know my geography better, but I don't. I . . . when I follow weather in Alabama, they always talk about Cheaha Mountain. Where's that?

Bob Newberry: Oh, yeah, that's between Annes and Gadsden, to the east of Alabama. That's the highest point in Alabama.

Kirk Harnack: Okay.

Bob Newberry: I couldn't tell you exactly what the height is.

Kirk Harnack: In fact, when I . . .

Bob Newberry: I'm sure that it's . . .

Kirk Harnack: . . . first met you . . .

Bob Newberry: Go ahead.

Kirk Harnack: . . . several years ago, it seems like you had just installed a bunch of Logitech consoles in your control room.

Bob Newberry: Yeah.

Kirk Harnack: And you were looking . . . and you had just installed a backup STL system to your HD stations, and you ended up using some high-quality . . .

Bob Newberry: DragonWave.

Kirk Harnack: . . . expensive IP radios.

Bob Newberry: Yeah. Those were the DragonWave AirPairs. And they're still running. They're nine and a half years and counting.

Kirk Harnack: Wow.

Bob Newberry: We have two of those. Well, the newer ones is a DragonWave Horizon, and one goes to our Eschuda tower, and the other one goes to the Golden Crest tower. But they're 100 megabit, full duplex radios. So they're carrier class radios.

Ubiquity wasn't out then, but there's a new Ubiquity radio I'd love to try out if I can find the excuse to use it.

Joe Talbot: AirFiber?

Bob Newberry: AirFiber, yeah.

Joe Talbot: Yeah, yeah.

Bob Newberry: It's . . .

Joe Talbot: I had those . . .

Bob Newberry: I think the point-four . . .

Joe Talbot: . . . radios, the DragonWaves, in my station in San Francisco, and they were pretty good. But boy, those were expensive at the time.

Bob Newberry: They were very expensive. I think we paid $25,000 per system for both ends of it.

Joe Talbot: Same here.

Bob Newberry: But they're very reliable.

Joe Talbot: Oh, perfect. They're great.

Bob Newberry: The 18 gig radios, the short path is the mile, and that just keeps running through any kind of weather.

But I do occasionally, if we have a torrential downpour, I'll have a little problem with that. It's a five mile path going the other direction, with two-foot dishes. So I could either increase the dish size, or . . . right now what I do is fall back to our 950 equipment, and the HD just kind of goes silent till the rain cloud passes.

Kirk Harnack: To bring up to speed any non-engineers listening or watching, we're talking about studio transmitter lengths. So getting audio from the studios, where the content creation happens, and getting it out to transmitter sites.

And, you know, traditionally, in broadcast, broadcasters have used wired facilities, like T1 circuits from the phone company. But very often, they use radios, analog radios, and then along came some digital modulation techniques in the 950 megahertz band. That band is not quite microwave, not quite considered microwave, and it does okay in the rain.

Now, you know the higher you go up in frequency, the more rain -- which we call hydrometeors -- the more hydrometeors attenuate the signal that's trying to travel. So you go up to these really high frequencies, like 5, 7, 18, 20- something gigahertz, and they're quickly affected by rain in attenuating the signals.

So, Bob, that's what you're referring to. You still have a backup at 950 megahertz in case you just get a torrential downpour and the microwave signal becomes unusable.

Bob Newberry: That's right. We also have IP at 928, the ISM band. What people usually call land link. It's diplexed in with the STL dishes.

Kirk Harnack: Yeah.

Bob Newberry: So it makes a very easy installation. There's no separate antennas to install.

Kirk Harnack: What kind of bit rate do you get out of a 900 megahertz ISM band radio?

Bob Newberry: Well, it depends on how much of the bandwidth that you're using. They don't give you a lot of channels. The way we're set up . . . I think we're doing, I want to say 10 megahertz bandwidth. But we get, like, a choice of four channels.

Fortunately, there's nobody else down there because of the . . . you don't get quite the throughput at that band that you would at a 2 or 5 gig bands.

Kirk Harnack: Right.

Bob Newberry: But with these Ubiquity radios we're using, we can do 3 to 4 megabits per second.

Kirk Harnack: Oh, goodness. Okay. So you could do coded audio comfortably.

Bob Newberry: Yeah. Yeah, we have our SIP telephones out at the transmitter sites, even on a double hop of these Ubiquity radios.

This is the little radio we generally use. It's a unit . . . what do they call this? A . . .

Kirk Harnack: Nanobridge?

Bob Newberry: A nanostation.

Kirk Harnack: Nanostation. Okay.

Bob Newberry: Yeah. The nanostation M900. But we're . . .

Kirk Harnack: Oh, so that's a 900 megahertz IP radio.

Bob Newberry: Yeah. We're on 928, is where that band is. But . . .

Kirk Harnack: And before the show, you were telling us that you don't . . . now, that's an antenna and a radio together. You disconnect the antenna, and you . . .

Bob Newberry: Yeah. This is a flat antenna.

Kirk Harnack: Yeah.

Bob Newberry: And you, in the software, you can disconnect the built-in antenna and go to an external antenna. And there's a connector in there. It's a tiny little reversed SMA connector. And it's like that's the connector.

Kirk Harnack: Oh, yeah.

Bob Newberry: And this is the adapter that goes to regular N. And then that N will go on your diplexer that you use to diplex into the same transmission line and antenna that you're using for your STL. Now, this is as easy as it gets.

Kirk Harnack: Joe, maybe you had experience with this. I never was lucky enough to do this. But some years ago, it must have been maybe 15, even longer years ago, the guys at Mosley came up with this idea. You've got a 950 megahertz STL. Hopefully it's a Mosley brand, as far as they were concerned. And there's this band right next to, or close to, the broadcaster's 950 band.

Joe Talbot: 928? 928, yeah.

Kirk Harnack: Yeah. It's got the ISM. What's the . . . industrial scientific medical band.

Joe Talbot: Instrumentation? Okay.

Kirk Harnack: Yeah. And so it's license-free. So you get some radios that are on that band. And guess what? Your 950 megahertz antenna will work okay for this stuff. It's not too bad off frequency.

Joe Talbot: [inaudible 00:15:02]

Kirk Harnack: And so if you diplex, you take these two radios -- your STL radio, the 950, and your ISM radio -- and you can diplex them together, and go up the same co-ax you have up into the antenna. And then the same thing at the transmitter side, receive it and split it to both. And now you've got a data link as well as your normal audio links.

And Joe, did you ever get to play with that stuff?

Joe Talbot: I never did the land link stuff. I did start getting into the Ubiquity stuff. I like the bullets, this kind of radio here, because it's got an end connector already right on it and a POE on the other side. And I use these all over the place. I've been using it as an STL at a friend's station now for about three years, and it's been terrific.

Plus they have these in the 900 megahertz band, the 2.4 and the 5 gigahertz band as well. And the thing I love about these is . . . and I just bought them as an experiment. These are cheap. This is, like, between $59 and $79 an act. You can do a lot of damage with that.

And, I mean, I remember I got the boxes, and I took them out in the field. I was out in the desert that day. And did a ten mile shot with a friend of mine. Just, boom, we just pulled up to the side of the road, had one at his house pointed down a particular direction, and we just . . . it lit up, and it just worked.

And that's been my experience with all this stuff. Never had a failure. But it's dirt cheap.

Kirk Harnack: I guess at that point, the diplex . . . if you're going to diplex it into your existing antennas, the diplexer ends up costing more than the radio does.

Joe Talbot: Oh, absolutely. The diplexer's critical, because you don't want to be fence-sitting any of your STL back into the radio. So, I mean, it's got to be tuned correctly and everything like that.

Kirk Harnack: Wow.

Joe Talbot: But that's pretty easy to do at those frequencies.

Kirk Harnack: I . . . before the show, Bob, you mentioned that microwave filter company sells these. And I just happened to look online, did a quick Google search for microwave filter company and ISM 950 megahertz. And sure enough, it's right here. It's their model 1846. It lets you combine or pass 944 to 952 megahertz. You know, that's the radio STL. And then the other pass band is 902 to 928 megahertz. That's the ISM band.

And so this lets you combine into one antenna or split from one antenna back to two radios. That's pretty interesting. I wonder what that box costs. Anybody know?

Bob Newberry: I want to say it's $700, maybe. $600 to $700.

Kirk Harnack: Okay. For each diplexer.

Bob Newberry: Yeah. I mean, it's metal. It's not plastic like . . .

Kirk Harnack: Yeah.

Bob Newberry: Not the Ubiquitous.

Kirk Harnack: [inaudible 00:17:30]

Bob Newberry: And I imagine there's a lot of tuning, you know? A lot of hand tuning that goes in on the thing that probably drives the cost up. But that's really the way to go. That gives you an IP connection, and you can put a little compared codex on there and use those for a backup STL. When you have problems with your main STL, you could just switch over to that.

We do that here, actually, as a tertiary way of getting out to our sites. We usually have a . . . besides two microwave systems, we have that running on the antenna, too. And that gives us . . . if we have trouble with the star link or something like that, we can switch over to that.

Or we also usually have an ISP, if we can, out of each transmitter site.

Kirk Harnack: Oh, yeah.

Bob Newberry: And we'll hang a little codec on that, too, to...

Joe Talbot: We've got customers using Axia nodes on that so it's uncompressed. Sounds like a million bucks.

Bob Newberry: Oh, yeah.

Joe Talbot: I've got a friend up in Palm Springs, he just lit up some radios, and he's got four channels going on right now.

Bob Newberry: Yeah. We do that on our DragonWaves, we have Axia nodes that . . . we have a node here, and we put all eight channels on it, and then run five one way and three the other on DragonWave radios.

Joe Talbot: Yeah.

Bob Newberry: It's kind of like a super snake, uncompressed.

Kirk Harnack: It is.

Bob Newberry: Works real well.

Kirk Harnack: It sounds good, too, I understand.

Bob Newberry: Oh, excellent.

Kirk Harnack: Amazing. And, hey, I'm really glad to know about that . . . the bullet that you showed, Joe, and the M900 that you showed, Bob. These are . . . the more you look into these Ubiquity radios, the more amazing this is.

I'll show you a little show and tell here. This is just 2.4 gigahertz, so it's Wi-Fi band, unlicensed. And here's the reflector. This is the small one that Ubiquity sells. And then this is the mount right here. The reflector, you know, goes on there.

And here's the business end right here. This is . . . the radio is here. There's an Ethernet right here. You power it with POE. And then this ends up all fitting together like this, so you have, you know, a focal point on all that. And you mount it up on the tower.

I've got to warn you one thing, though. If you plug these two things together -- the radio and its feed point, and all the electronics -- you plug it into the mount, you'll never get it back off again without doing some damage. So don't plug that together until you're done running the cable up through here, pulling it out, putting the RJ45 connector on, making sure it's good, plug it . . . test it first. And then, and only then, put this together.

And you may wonder, how do I know this?

Bob Newberry: You didn't order the special key that unlocks this pair.

Kirk Harnack: Do they have one?

Bob Newberry: No. I don't know. Just making that up.

Kirk Harnack: So what I did . . . I went to YouTube. I said, "How do you get it . . . how do you take apart a Ubiquity, whatever this is, radio?" And somebody showed, "Well, you put a screwdriver on here, and you turn real hard, and you pull it out."

What's that?

Bob Newberry: All right, Kirk. I'll go you one better on the show and tell.

Kirk Harnack: What's that?

Bob Newberry: I just bought this. This is a cross polarized 950 Aggie, okay? This long antenna.

Kirk Harnack: Holy cow. You can poke somebody's eye out with that thing.

Bob Newberry: You could very easily.

It's got two SMA connectors. Comes right out of the business end. And then you attach this Ubiquity radio. This is a rocket.

Kirk Harnack: Okay.

Bob Newberry: A Ubiquity rocket. And you see you've got your two connections on the top. They plug-in in there. This thing snaps onto here. Whole thing sits outdoors.

And I'm interested in trying this out, because you're supposed to get a pretty good throughput, because it uses a technology they call MIMO. Is that "mymo"? I don't know . . .

Kirk Harnack: Yeah.

Bob Newberry: . . . if you pronounce that or not.

Joe Talbot: Multiple in, multiple out.

Bob Newberry: Yeah. Multiple in, multiple out. It uses both V and H. It's still a simplex radio. Only one end's going to talk at a time. But it's going to be able to talk a lot faster. So it's supposed to go farther.

But I've got an application in mind for that. Between one of our FMs, we have a charter cable out there, and it's costing us about $130 a month. It's a backup. So I'm going to try to link that resource to our AM transmitter plant, which doesn't have a backup right now, of audio. And we have a land link out there, but this is going to be a second backup to give us internet service out at our AM plant.

And here, again, we'll hang another codec on there for . . .

Kirk Harnack: You know . . .

Bob Newberry: . . . a third backup.

Kirk Harnack: Joe, let me get your thoughts on this one. My thought on some of this technology is this, we're getting some tech here that is really inexpensive. Like, sub-hundred dollar parts.

Bob Newberry: Exactly.

Kirk Harnack: You know, the meat and the potatoes. The radio that does the work. Pretty cheap.

You still have to do the engineering right. We can't just toss this up and expect it to work. There's rain. There's ice. There's lightning. There's all the dangers of putting something outdoors. And it's going to be aimed right. It's got to be above the trees. Because this stuff is mostly line of sight.

It still requires knowledgeable . . . even though the stuff is cheap, it doesn't mean that installing it and planning it is going to be cheap and easy.

Joe Talbot: Right. Nothing is going to free you of that responsibility. So you've got to know your stuff, and you've got to take the time and do it right.

Kirk Harnack: I'm excited about trying some of this stuff out.

Hey, if you're watching the show -- and [inaudible 00:23:25] obviously you are -- this is Episode #218 of This Week in Radio Tech. I'm Kirk Harnack, along with Joe Talbot and our guest, Bob Newberry. Bob's the market director of engineering for Clear Channel in northern Alabama, Birmingham and Gadsden, and also Tuscaloosa.

We're getting around to our main subject here shortly. I'm sorry if we put it off too long. And that is Bob's adventure in finding out about SIP telephony. And that's pretty cool. So hang on, we're going to talk about that in just a minute.

Right now, I want to tell you about one of our sponsors, and that is Lawo, a console company out of Germany. And they make this incredibly cool console called the crystalCLEAR. It's a virtual radio mixing console.

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It does use this multi-touch enabled mixing control. That's the big touchscreen. Which, by the way, is a PC running an app, and it's tied by network to the DSP mixing engine that also has the audio inputs and outputs.

So it's one RU box that fits in a rack, and that's where all your audio inputs, including your mics, your analog and AES inputs and outputs go to. And then, with just standard computer networking, you hook it up to a computer, and they suggest using this beautiful HP multi-touch touchscreen PC running, I believe, Windows 8. And it just makes a beautiful, gorgeous-looking way to mix audio.

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We thank Lawo for sponsoring This Week in Radio Tech. Again, the website is Lawo, L-A-W-O, "lawhoa," dot com.

All right. We're moving on with Episode 218 of This Week in Radio Tech. Bob Newberry is our guest. And let's jump into what maybe I should have earlier in the show. That is SIP telephony.

You know, Joe Talbot . . . Joe, you've been a guest on the show before talking about this thing called SIP telephony.

And so I want to back out a little bit here. Bob, you told me before the show that you got interested in SIP telephony a couple of years ago as an experiment for providing cheaper and quality telephone service for your offices, and then maybe eventually for your studios in your smaller markets.

So tell us how you got started, and then you and Joe just carry on with this interesting topic.

Bob Newberry: Well, we just kind of jumped right in about six years ago. Birmingham had Avia that we were paying really a huge, exorbitant amount for maintenance, $850 a month just on the maintenance contract with the Avia gear. And it's good gear, no doubt.

But I started looking on the internet at this Asterisk. And I wasn't real sure what it was, so I read up on it, and went to these VoIP.org and the Asterisk website, and a few other websites. And I found a website called Elastix. That's E-L- A-S-T-I-X. I think it's dot org, if I'm not mistaken.

Joe Talbot: It is.

Bob Newberry: But they make a distribution disc that takes the Asterisk open source software, and they add it with free PBX, and they package it up with their front end on it, too. It's a GUI front end. Because if you . . . a lot of people that started out Asterisk the old way was you had to do it through Linux, and I'm just not that good at it. I don't know a lot about it.

So I just took this distribution disc we downloaded, plugged it into a PC I had, and lo and behold, 15 minutes later I had a functioning telephone system. But I didn't have any telephones.

So the next thing I did is order a couple of cheap SIP telephones to try it out. And I just sat in our technical center and made a call from one ear to the other and said, "Hey, that works pretty well."

So the more confidence I gained in it, we decided . . . in Tuscaloosa, we had some little basic phone system mounted on the wall with about 15 telephone sets, and it was at the end of its life. So I decided to go ahead and try it over there. And we ordered a PRI circuit.

And Digium, the company that makes Asterisk, also makes these PCI cards that plug into the computer. And they make T1 cards, they make cards that deliver POTS lines, telephone sets. That would be called an FXS card, for foreign . . . what's that, Joe? Foreign exchange station . . .

Joe Talbot: Station.

Bob Newberry: . . . I think?

Joe Talbot: Yes. Foreign exchange office, FXO, and foreign exchange station.

Bob Newberry: Yeah. Those cards really aren't that cheap, but I can't remember exactly what we paid for them. But they're in the thousand dollar range for, like, eight ports.

So we got two of those cards, giving us 16 POTS lines, basically, and a card that gave us a T1 input that we plugged the PRI into. And that and 15 telephone sets, 15 to 20 telephone sets, I can't remember exactly, were in Tuscaloosa, and that gave them a functioning phone system that worked in the offices as well as the studios.

Joe Talbot: With voicemail and everything.

Bob Newberry: I didn't know any better. I just jumped right in and did the studios, too, you know, with the Asterisk system. It's not a separate line driving the studios over there, or here, or anywhere in our little fiefdom.

But one of the other things . . . once we gained experience in the Tuscaloosa market for a couple of years, I felt confident enough that I could do it here in Birmingham. So we did the same thing using about 35 telephones and four of these Digium cards and a computer to give us 32 POTS lines, which we fed to all the control rooms. We have Telos 2 by 12s in each control room.

And that gave us a fully functioning telephone system for about . . . I want to say about $15,000. Very inexpensive. We've never really had any trouble out of it. And the audio quality's real good. Excellent.

And another thing we found out we could do is you can talk from Asterisk to Asterisk. And so we put in these circuits between Birmingham and Tuscaloosa, and then Birmingham over to Gadsden, and recently down to Montgomery. Our Montgomery station, Josh Harten's the engineer down there. And we . . . I talked him into doing this.

But we set up Asterisk down there. So now all four of these Asterisk systems are tied together with an Asterisk protocol called IAX, I think. Is that right, Joe?

Joe Talbot: Yeah, it is. That's the trump protocol. It works really well.

Bob Newberry: Yeah. Interactive exchange.

Joe Talbot: We use it with Telos. I've got about a dozen stations all tied together with it, also.

Bob Newberry: Okay. You know, yeah, I was . . . I got real interested in the . . . in setting up the dial plan or the routing of these calls. So if I pick up my phone and I dial an extension in Tuscaloosa, it goes over our point to point circuit, and not out to the provider and back in there provider. Which is . . . it's all Windstream down here.

But that way . . . or if I want to call a business in Tuscaloosa, just any other business not even associated with us, when I dial the number, the dial plan sees that it's a Tuscaloosa number, and puts it on point to point, and goes out their PRI out there. So it makes it a local call.

Joe Talbot: [inaudible 00:33:56] routing.

Bob Newberry: Kind of you avoid toll charges that way. Not that that really adds up to much in this day and age.

Joe Talbot: [inaudible 00:34:05]

Bob Newberry: But it was more the interest in being able to do that.

I'm sorry?

Joe Talbot: Oh, I said the far end hop-off like that in least cost routing is really elegant.

Bob Newberry: Yeah.

Joe Talbot: It just seems like you should do it. I mean, realistically, long distance doesn't really cost us anything in these days.

Bob Newberry: It doesn't.

Joe Talbot: For the most part. But it's nice to be able to keep the calls on your network and have them never touch the public network at all.

Bob Newberry: Yeah. When there are problems with the public network, this is a way of getting around.

And I was talking with Jeff Peacock in Mobile, our Clear Channel Mobile facility, about being able to do . . . see, he's got Asterisk from about probably 10, 12 years ago. He's an early adopter. But he doesn't have . . . he's not providing it with SIP service yet. I think he's still using a PRI or individual lines.

But once you go SIP, that opens up a whole other world of being able to do a lot of things from the provider levels. And we were talking about, if he had a hurricane down there and had to abandon his studios, for whatever reason, we could instantly channel his phone lines, studio phone lines, up to our studio, and go on the air up here, and feed his transmitters through the Clear Channel's . . .

Joe Talbot: How do you do that? You have to contract Windstream, or a provider? How do you get [inaudible 00:35:33]?

Bob Newberry: Well, Windstream, you do it online, you log in, and you can do it instantly. As long as everybody's on SIP.

And I guess I got ahead of myself when I was talking about Asterisk. We started out using PRI and Asterisk, because I just didn't know anything about SIP. I knew it worked SIP on the set side, but I didn't know how to apply it on the provider side until I learned a little more. So it was a little learning experience over a couple of years before I took the plunge.

And we did that first over in Gadsden, a very small Clear Channel market. We were able to get Windstream to give us SIP service. And that eliminated the need for the PRI.

And the good thing about Windstream doing that is they also provide the QOS. Because they put the router out at your location. And so the QOS is put on the SIP traffic, so it's number one priority. And then all your internet services, every . . . and point-to-point data is the lower priority.

So the call quality is real good. Very good. Very rarely have any kind of stutter in it. It's good enough to put on the air, so we did that in all three markets.

And now, tomorrow, actually, in Tuscaloosa, we're finally going to drop that PRI and go to SIP service with Windstream over there.

Kirk Harnack: Wow. Wow.

Bob Newberry: That'll tie . . . that'll give us all four markets with Asterisk via Windstream with SIP audio.

Kirk Harnack: Bob, what would you say that somebody like me . . . I'm getting ready to move my own little radio station to Mississippi, and we're thinking of going to SIP for our on air lines. We already do a hosted PBX solution for business circuits.

What do I need to go be looking into? And we're not as big as Clear Channel, of course, so I'm not sure . . . I guess we're going to go with a cloud provider and our internet connection.

Do you have some suggestions about what I need to look for?

Bob Newberry: I wish I did. But the question I still have is QOS, and how do you maintain your quality of service on your SIP packets, and make them the most important thing to that provider. If you're dealing with a cable company, maybe, that has their own SIP service, or Vonage. From what I understand, my limited knowledge of Vonage, I think they provide a router to your house. To your business.

Kirk Harnack: It's . . . no, it's a little . . . yeah, okay. But they . . .

Bob Newberry: But you can't really do QOS over the public internet.

Kirk Harnack: Correct.

Bob Newberry: I mean, once it gets onto the internet, isn't it every man for himself, every packet for himself, basically?

Kirk Harnack: Exactly.

Bob Newberry: Okay.

Kirk Harnack: Pretty much, yeah. Unless you're Netflix or you're paying extra, so, yeah.

Bob Newberry: Yeah. And that's why I felt confident going . . . you know, being with Windstream, or AT&T, or any large provider, that they're going to be able to handle that aspect of it, at least through their switch.

The other benefit of our situation here in Alabama is that Windstream's switch is in Birmingham, even if you're in Tuscaloosa or Gadsden or Montgomery. Their only switch in the area is in Birmingham. So it all flows real well, and it all gets the top priority, as far as getting those packets through.

Kirk Harnack: So, Joe, it sounds like . . .

Bob Newberry: And that was my big worry.

Kirk Harnack: Yeah.

Bob Newberry: You know, you can take a little hesitation on a phone call in your office, but you don't want that on the air. It's got to sound good on the air 100% of the time. And it does. It does work real well.

Kirk Harnack: Joe, it sounds to me like these providers, like Windstream or others, that bring fiber or bring copper to your building . . .

Joe Talbot: Usually copper, yeah.

Kirk Harnack: Yeah. Are they promising service quality right up to that point?

Joe Talbot: Typically, yes, because most of these situations, it's going to be a T1 to the premises, and they're going to put a device on the wall. A router, basically. The device called an IAD, which is . . . let's see. Integrated access device.

Kirk Harnack: Okay.

Joe Talbot: It's a router. It's generally got a PRI port or two. It might even have some POTS ports on it. They'll do that, and . . .

So what they typically do is they run a software package, and they'll provide a little bit of internet and some voice, and the voice is set up with priority. And they're actually on separate networks. It isn't like they hand you the internet and then you hook up your stuff to the internet. There's a special IP address. You know, a special network block they stick you on. And it's pretty much a point-to-point circuit, or at least controlled.

Kirk Harnack: Got you. And with that kind of service, you're not competing with other packets. That's almost like bringing in PRI or T1 in terms of the quality of the connection between you and that provider. Right?

Joe Talbot: Right. I mean, you're literally talking directly to them.

In the situations where you have to use the Internet . . . like, maybe your little stations. I'll put in a DSL, because typically a DSL has less jitter. You know, the speeds don't vary as much on a DSL as they do on cable company stuff.

I mean, even when I'm talking to you sometimes on some of our, you know, company meetings, I'll have issues my end, and you have issues on your end. And I've got . . . all my voice traffic here is DSL. All my regular data traffic is either through the cable company, which is miserable, or more often it's over the wireless. I have a carrier here in town that gives me a 5 gigahertz connection. And I get about 7 megs down from them and about 2 up, and the jitter is acceptable.

But the jitter on the DSL is actually the best. And the DSLs are really slow. They're . . . one's a 1.5, and the other one is a 3, and 768 k up.

Kirk Harnack: Yeah.

Joe Talbot: So they're just really tiny little circuits, but there's very low jitter on them, and they're cheap, too. So that's what I use.

Kirk Harnack: Got it.

Bob, if you had to do again . . . you kind of took us through your learning process. You started with a station where you couldn't make a . . . you could make a mistake if you had to, in Gadsden. What . . . if you do it over again, where would you go to learn about this? How would you get yourself up to speed on SIP?

Bob Newberry: I don't think I'd do it any different than what I did. It's great to get that distribution disc from them, put it in a PC that you are not using, and it'll rewrite the whole hard drive with Linux and all the applications.

And that, other than that, going, reading a lot online. You know, if you type in "Asterisk," do a Google search, or say a particular problem you're having, you start typing the problem in the Google box, it finishes the sentence for you.

Kirk Harnack: Yes, it does.

Bob Newberry: Because it knows.

Kirk Harnack: Well . . .

Bob Newberry: And there's thousands of people that had that same problem. And the answer will be out there.

Kirk Harnack: Yes. Yeah. I sure have . . . in fact, I . . . hey, Joe, I told you earlier today when you and I were talking. Last night, I kind of took the plunge and said, "I'm going to order a, by golly, cloud SIP provider phone line."

So I went onto Vitelity.com, or net, or whatever it is.

Joe Talbot: Great.

Kirk Harnack: And I signed up, gave them my credit card. I got a phone line, a SIP line. I didn't realize till later that I needed to associate it with a number. So I did that.

And then I thought it was all working okay, but then . . . so I was using . . . I've got some hard phones that I could use. But I have an app, Joe, that you introduced me to. It's an app called Bria.

Joe Talbot: Oh, yeah.

Kirk Harnack: And it's a paid-for app. And so I couldn't . . . I could get it to register, but I couldn't make a call. And even on Vitelity's online status page, I could see that this phone was registered with their SIP server, but it wouldn't make . . . it would drop the call immediately.

And so I . . . Google's your friend, right? I Googled, as much as I could figure out how to describe it, this problem. Well, the problem was that I didn't have the codec selection in the right order.

And, Joe, you may remember, some months ago, I was at your office, and we were playing with AMR wideband. And so I still had AMR wideband selected, and G711 wasn't selected.

Joe Talbot: Got it.

Kirk Harnack: And so I fixed that. Because I'd had the app for months. And so I fixed that, put it in the right order. Bam, made a phone call, and it worked. And Google's your friend.

Joe Talbot: One thing about Vitelity, too . . . and I dread calling tech support for companies, because everybody's overtaxed, and it's usually kind of a drag. But the guys at Vitelity are amazing. I have friends there, and they will call me with wanting me to test things for them sometimes. And they'll call me, and they'll say, "Have you experienced this?"

And I've had some really off the wall problems with other providers, and I've been able to explain it to them, and they've been able to get to the bottom of it and get it fixed. I mean, they take it as a personal challenge. So it's not your usual . . . I mean, you don't get some call center in India who's reading you cards. It's totally different. So they're pretty good that way.

Another company that's good is one called Voice Pulse. Those are my two favorites right now.

I'm also using one called FlowRoute out of Vegas, and they've been very good. But sometimes getting examples of how to set things up can be difficult. Although Vitelity has, on their support page, actually has stuff you can cut and paste right into Asterisk or whatever to get set up, and that helps me a lot. Just . . .

I mean, I can do it manually, but it's so much better just to cut and paste, and not have to worry about taking the time to, you know.

Kirk Harnack: I've got to point out, this is a skill set. This is a knowledge set that most of us broadcast engineers don't have. And so it's all new.

And now, last night, I was playing with the Vitelity website, and they were using some terminology that I couldn't guess, I didn't understand. I ended up taking a couple stabs at it, and eventually got it right.

But Bob, did you notice this, that the . . . you've got to fill out a field, and you don't quite know what goes in there?

Bob Newberry: Oh, yeah. I've run into that. Like the SIP registration string that you have to put in. And that . . . I was sweating bullets, I think, in Gadsden, our first experience with a SIP provider, and trying to get the registration string. Which is a long string of numbers, basically, and passcodes, and everything else, to get registered. So your SIP server talks to the provider's SIP server.

Yeah, it was a hard experience. Hard learning experience. But once it connects, it's really great, because it just . . . there's . . . Asterisk gives you a lot of login information, so you can really spot a problem pretty quickly and find out whether it's a problem on Windstream's end or on your end. And that works pretty well.

You were talking about Bria earlier. I've got Bria on my laptop and on my tablet. And about five years ago, when I was still learning this, we had it only running in Tuscaloosa. Our program director took a missionary trip to China. I'm not sure exactly where he was in China, but he had Wi-Fi in the place he was at.

So he took his laptop, and I put Bria on it. And he went over there. And, of course, our Asterisk system is behind the Clear Channel firewall. But he activated his VPN and brought up Bria, and started making phone calls. And he said it worked so well, he had the other missionaries, the people over there on this missionary trip, in line wanting to . . . waiting to call home from his laptop.

Bob Newberry: Because it was a . . .

Joe Talbot: Are you guys . . . oh, I'm sorry.

Bob Newberry: . . . better and cheaper than they could from the hotel room.

Joe Talbot: Absolutely. Are you guys using the wideband, the G722, codec. Pardon me, HD audio. Are you using that on your systems out there?

Bob Newberry: No. I haven't tried that yet. And I've been talking to Ed, my IT guru, about that. And we want to do an experiment.

You know, actually, even with 711, with a good microphone on your tablet or your phone, it actually sounds pretty good. But I do want to try that.

Joe Talbot: Yeah. Give it a shot. It'll blow your mind. I mean, we have stations that are using it for their news departments, or they're using it to go out to do remotes and so forth. And they just come in on the public internet with a G722 call, and it rings into their VX, and VX supports it natively, so it sounds . . .

Bob Newberry: That's key, though. Got to have that VX.

Joe Talbot: It's amazing.

Bob Newberry: Right now, I've got to go down to POTS lines and go into a standard . . . into our 2 by 12. Although it's only . . . you know, you're talking about 100 feet from the asterisk to the Telos in the other room.

But I don't know if there's a roll off on that or not.

Joe Talbot: There is.

Bob Newberry: What the bandwidth would be, or the available bandwidth on a POTS line, given 722 into the front end of it. Do you know? I mean, would it . . .

Joe Talbot: It's not going to help you a lot. I mean, the first thing in an analog telephone interface, the first thing that it hits is either . . . if it's a digital, one of ours, for example, like a 2 by 12, it hits a codec, and the codec has a 300 to 3000 hertz [inaudible 00:49:40] . . .

Bob Newberry: 300 to 3000, right.

Joe Talbot: So it's got rolloff on the low end. Which makes, actually, the biggest difference in terms of warmth and naturalness.

Bob Newberry: Yeah.

Joe Talbot: And it has, of course, a brick wall filter on the high end, so that gives you that classic telephone sound.

But when, you know, if you get a chance to play with a VX or one of our other codecs, it'll blow you away. We showed it at NAB, and people were having a really hard time believing that's what it was.

Bob Newberry: I imagine. I imagine. Our original installation, over 2 by 12s, we had ISDN interfaces, because our Avia, we had ISDN ports on it. And that was really the classy way to go.

Joe Talbot: Oh, yeah.

Bob Newberry: I mean, call setup was almost instantaneous over the PRI circuit. But when we went to Asterisk . . . I researched and researched ISDN on the station set side, and could find no information. Evidently they use it in Europe a little bit, but there's very few places in America that use ISDN on the telephone set side.

Joe Talbot: Yeah. The system that I've got here at home, and actually the one we have at Telos, the Millennium, Core Telco Millennium . . .

Bob Newberry: Oh, okay.

Joe Talbot: This actually is an ISDN telephone. And it's an ST interface, a European-type interface. But also, there are cards for Asterisk you can buy that do the ST interface. And we play around with that a little bit. And you can do it. You just can't do circuit switch data through trunks. There's no support for any of that.

Bob Newberry: Oh, okay.

Joe Talbot: Go ahead . . . I'm sorry?

Bob Newberry: I went with a company called Zercom. They made these Astrobanks.

Joe Talbot: Yes.

Bob Newberry: They're one-rack units, then their USB connected to your Asterisk computer. But they said . . . I bought these on the premise that they would do that. And then after going back and forth with the factory for, like, months, they said, "Well, it's not going to work."

And so that was the end of that. We just had to pull them out.

Joe Talbot: Yeah. The magic words are "circuit switch data."

Bob Newberry: But you're saying somebody can do that now?

Switch data.

Joe Talbot: And, like, if you've got a Telos Extreme or something like that, and you want to run it through Asterisk, it's not going to be a good experience.

Bob Newberry: Yeah.

Joe Talbot: If you do run it through one of these Millennium switches, it will work just fine, because it's an ISD kind of a reference switch. I mean, it fully implements everything.

Bob Newberry: Oh, okay. But that's the time long ago, now.

Joe Talbot: I know.

Bob Newberry: ISDN. I think it's becoming harder and harder to find, anyway, other than with a PRI.

Joe Talbot: It is.

Bob Newberry: And that's going away. Channelized data.

Joe Talbot: Were you using the . . . a USA-type U interface, or the ST interface, on your Avia when you were using that?

Bob Newberry: It was, like, the USA interface.

Joe Talbot: Okay. The two-wire interface. Got it.

Bob Newberry: Yeah. The two-wire interface.

Joe Talbot: Okay.

Bob Newberry: Yeah. Each Avia, I think it had eight ports. So we had several of those circuit cards in there. And each phone, the 2 by 12 has two ports for a total of four B channels. I think that's the way it was.

Joe Talbot: Right.

Bob Newberry: So we had to pull those cards out and plug in the POTS cards when we went to the Asterisk. But . . .

Joe Talbot: We have a lot of customers that are using either PBXs, or, like, Atlas, or Adtran devices, to take a PRI and break it up into individual BRIs.

Bob Newberry: Oh, yeah.

Joe Talbot: But you can get PRIs easily enough, but BRIs are about to become impossible to get, and very expensive to get.

Bob Newberry: Yeah.

Joe Talbot: But a lot of . . . most of the Telos gear -- just about all of it, in fact -- has the ST interface available. The four-wire interface. If you've got an extreme . . . just move the plug over to the four-wire interface.

At my last radio station, all of our codecs were behind the PBX and were fed with PRIs. And it was dirt cheap, and it sounded great. Very reliable.


Bob Newberry: Yeah. We have an Adtran Atlas 800 here in Birmingham that we use, feed . . . well, we're down to one . . . we had, when we were running the Avia system, we had three PRIs. But when we went to SIP, I kept one PRI just for all our zephyrs and other codecs to use. And so it's not being used as much as it was originally.

But that's a good system to have.

Joe Talbot: Yeah. We'll use it for codecs and fax machines. Stuff like that.

Bob Newberry: I was going to bring that up. A fax machine. It's one thing . . . Windstream they wouldn't guarantee fax machines on their SIP service. They said it works, but if you're a high-volume fax user, they wouldn't recommend it. But we get away with it. We've had no problems with it. All our faxes seem to come through.

And that's G711, I think. Same codec they use.

Joe Talbot: It is.

Bob Newberry: It's probably not supposed to work, but it does work. And I'm waiting for the fax machine to go away eventually.

Joe Talbot: Yeah, there may be some impairments once in a while, and the speed . . . I mean, it is a modem, after all, and modems don't work well through . . . excuse me, modems pretty much don't work at all through VoIP.

Bob Newberry: Right.

Joe Talbot: If you ran, like, a 103. Nobody runs those anymore. Or 202, you might be able to get away with it.

Bob Newberry: The local system might, yeah.

Joe Talbot: Yeah.

Bob Newberry: The basic, like, ADT alarm systems, like 300 BOD, I think they'll work.

Joe Talbot: Yeah. A lot of that stuff is . . . some of that stuff's DTMF. I won't say a lot of it. Some of it actually sends a bunch of touch tones. And there are some issues sometimes, depending on your provider and the way you have things set up, with DTMF. I mean, you've probably seen RFC2833 option for DTMF. That's the most common, best way to do it.

There's also inband, and there's a couple other different options. But pretty much everybody standardized on RFC2833.

And once in a while, you'll get a provider that has it set wrong, and you'll send a touch tone, and it just won't make it through. You won't hear anything. Or I've actually had circuits where you heard the touch tone twice because you had something set up wrong.

Bob Newberry: That's the kiss of death with an engineer that uses touch tones all the time to talk to the transmitter sites.

Joe Talbot: Exactly.

Bob Newberry: I mean, that has to work.

Kirk Harnack: Yeah, but that might go away someday, if we can get just real easy IP connectivity.

Bob Newberry: Yeah, because the touch tone . . . or the dial tone, DTMF, is . . . in fact, I think it's generated locally in the phone, just for your confidence. When you push the buttons, you're not sending that DTMF from the phone to your PBX. You're just sending the digit. And it's just . . .

If you're going on a POTS line, it has to generate that DTMF tone locally.

Joe Talbot: I was dealing . . .

Bob Newberry: And what you hear in your ear is just locally generated for your confidence, that you actually pushed the button and it worked.

Joe Talbot: Exactly right. When we were doing the early VX development, I was working with the provider -- I mean the developers -- over in Europe. And the system at that time didn't make any of the tones.

And I said, "Well, it's got to do that, or people aren't going to think it's working." And also, people here in the US, companies have automated attendance that you have to be able to blast through. If you call a company, you never get a person anymore. And they thought that was just bizarre.

But they put it in. And so the VX does some kind of amusing things with the tones. It plays tones in your ear when you're on the handset for your, you know, confidence. And if you're actually dialing on the air, it substitutes the tones that are being played over the air with different tones so that the phone number you're dialing is not given out over the air, effectively.

Bob Newberry: Oh, I like that.

Joe Talbot: So it kind of scrambles them, and plays some tones that sound like touch tones, but aren't.

Bob Newberry: Yeah. Yeah.

Joe Talbot: And also lets you do things like upload your own funny noises to take the place of touch tones, if you wanted to do that. So we started fixing it, we went a little overboard and added some fun stuff, too.

Kirk Harnack: Hey, guys. We're going to take a quick pause here. Think of how we're going to wrap the show up after we hear from our sponsor, Telos, and the Telos Z/IP ONE.

You know, I've talked about the Telos Z/IP ONE quite a bit, because I just love this product. It does great. We use it in our radio stations.

I've got one right here behind me. You can just about see it on the video. This was just connected... it's connected to the same internet service that my Skype is going out on right now.

And I'm going to hit a button here, auto. I'm going to dial another Z/IP ONE that's actually, I believe, in Austria.

How about that? It connected that fast. I'll do it again. I'll show you that again. Here, watch. Auto, and auto again.

That is... let's see. Let's turn that down a little bit. Let's see if I can tell you what the codec is that's going on right here. I'm receiving from them HEAAC at 96 kilobits per second, and I'm sending AAC at 128 kilobits per second. And that's connecting to Austria. Austria. And I'm in Nashville, Tennessee.

So, hey, I've been connected for weeks at a time to other Z/IP ONEs. And you know one of our guests here on the show, Dave Anderson, Dave uses Z/IP ONEs. He's got almost 40 of them now. Uses them as STLs to transmitter sites that otherwise they just couldn't afford to feed all these transmitters and translators with traditional, expensive STL systems. So they use high bit rate codecs. They use medium bit rates in a couple places where they have to.

So the Z/IP ONE, what is it? Well, it's an IP audio codec. A very professional one. It's got different algorithms in it, like MPEG layer two, and AAC, and HEAAC. One called AACELD. That's enhanced low delay. And just regular low delay, as well.

And plus, optionally you can get APTX, aptax, if that's your standard. You hook it up to an internet connection or to a dedicated LAN or to an IP radio.

It'll also, by the way, do linear. And that was an experiment that Brian Jones and I did. Linear audio, 2.4 megabits per second from Washington State to Tennessee for five weeks.

Now, it may have hiccupped when I wasn't in the room, but it never hiccupped when I was sitting here in my office listening to the great Christmas music that Brian Jones was providing during the last holiday season.

Point is, the Z/IP ONE is this ultra-cool box. It lets you go out, hook up to other people's internet, hook up to wireless services like Clearwire or Verizon 4G LTE. Go do a remote broadcast.

Hey, we just heard from a station in Cleveland, Ohio. A public radio station, WCPN. And they went out and did a live remote broadcast from one of these all-natural, locally produced milk dairies, where they were . . . it's an ice cream shop, and they have fabulous ice cream, made with locally harvested, locally milked cows, and locally sourced ingredients from the farmer's market.

Anyway, they did a broadcast interviewing the owners and some other guests. You can find that interview. It's on the WCPN website. I'll put a link to it in the show notes.

Point is, people are using these for live remotes, for a talent. Disc jockeys, announcers who maybe have to work from home. For voiceover work, and for studio transmitter links to get audio from the studio to the transmitter and bring it back. Or maybe you've got a satellite dish on the transmitter site, and you need to bring that audio back reliably.

It handles contact closures that remain in sync with the audio. It handles RS232 data, as well.

So that's enough about the Z/IP ONE. You ought to check it out for yourself. Go to the Telos website at Telos-Systems.com, and click on the Z/IP ONE. You'll find all kinds of uses for it. Once you understand how to get it hooked up to IP, it is really great. You're going to enjoy it.

And, hey, I use it at my stations. We do a couple of cool things with Z/IP ONEs ourselves. And there are literally thousands of them now all around the world.

Thanks, Telos, and thanks to the Z/IP ONE for sponsoring This Week in Radio Tech.

Well, guys, we're almost out of time. Bob, I wonder what kind of closing thoughts you might have for us about SIP telephony.

Bob Newberry: Well, I'll let you know tomorrow when we finally do our final conversion from our last Asterisk install that has a PRI that we're going to convert to SIP. That's tomorrow.

Kirk Harnack: Okay.

Bob Newberry: And I don't anticipate any troubles. I think it'll work just fine. And then I'll let you know after that.

But SIP's the way of the future. So you've got to put that telephone hat on if you want to be an engineer, I think, these days. You can't just call the phone company. It's really . . . it's a computer, and it's an IP audio device. So it's really kind of getting more into our expertise more and more, like you said earlier in the show that you almost have to know telephone these days to work in radio.

Kirk Harnack: Joe, I like the fact that if you're . . . when you get into SIP telephony, you can end up saving money and/or improving the quality. And if you do it right, your reliability can be as good and maybe even better than we've been accustomed to with Telco services like POTS and PRI. Isn't that right, Joe?

Joe Talbot: I think so. I've saved a ton of money using it.

But, I mean, nobody cares more about your stuff than you do. And that's why, rather than sit on the phone and talk to some help desk, where they're writing things down and completely screwing up your trouble ticket, I'd rather just do it myself. I'd rather own the problem. I'm okay with that.

Not everybody is, and we're all wearing a bunch of hats these days. But it's not so bad to be the phone man. You're way smarter than they are, so you might as well take advantage of that fact.

And how did you keep Bob away from you? He sounds like me. We need to talk.

Kirk Harnack: We do.

Bob Newberry: We do.

Kirk Harnack: Yeah. I want to try out this . . . some of this . . . you know, we're big fans of free PBX, building our own. And I've got free PBX running on this raspberry pie, right, here in the office, to provide dial tones to a few phones and connect me to Google Talk.

But I want to try out some other distros, too. There's elastics, that Bob happened across, and he's liking that very much. These are based typically on Linux, and so you get a distro CD, and you put it in, you wipe a whole computer out, and now you've got a computer running Linux that you may not know much about. But the good news is you get this GUI, and you can immediately start building a phone system and making it work.

One of the things about SIP, though, is you don't have to do it all yourself. You can have this stuff hosted elsewhere, if you want to pay for that, and the support and convenience that may go along with that. That's how my stations do it for our business phones. We pay 8 by 8 to host it for us.

And, you know, that has certain advantages, and it may have certain disadvantages, too. But they've been very responsive, too.

Point is, you've got a lot of options. You've got a lot of options when you go to SIP for delivery, and for who's providing the service, how it's in and out of your station, and how you're going to program it, and what you're going to do with it.

Wow, guys, thanks for being with us.

Joe Talbot: Thank you.

Kirk Harnack: Bob Newberry, market director of engineering for Birmingham . . . for Clear Channel in Birmingham, Gadsden, and Tuscaloosa. Appreciate you being here, Bob.

Bob Newberry: It's a trip. Glad to be here, Kirk. Good to meet you, Joe.

Kirk Harnack: Hope you join us again some . . .

Yeah, Joe Talbot from Area 51. Thank you for being here, as well. I appreciate it.

Joe Talbot: Always a pleasure, Kirk.

Kirk Harnack: Wow. Thanks again. Thanks again.

Hey, if you want to know more about either of our sponsors, Lawo, it's L-A-W-O dot com, and Telos Systems is Telos- Systems.com.

Thanks a lot to Andrew Zarian back at headquarters with all the equipment there, switching the gear around, switching the cameras, and making us kind of look sort of good.

Andrew, I appreciate you being here, and the entire GFQ network.

We'll see you next week on This Week in Radio Tech. Bye-bye.

Topics: IP Telephony, Radio Technology, sip