Best Way to Connect 2 Radio Stations to Send Live Programs to Each Other?

[everydayguy]

Another newbie question from a newbie engineer:

I'm helping a friend with his two recently-purchased AM stations in the Midwest that are about 35 miles apart. I was wondering how you would handle this situation.

First some background --
1. One of the stations (I'll call it "Station A") has a C band satellite dish for downlink.

2. The other station ("Station B") does not have space for a C-band dish.

3. "Station B" needs to capture some national programming on C Band, but since it does not have a sat dish, "Station A" will downlink the program. He needs to get the live sat feed from "Station A to Station B."

4. In addition,"Station B" would also be sending some of its live programming to "Station A."

So my questions are:

* What is the most reliable way for the two stations to send mono programming feeds back and forth to each other -- a fixed microwave conection is not available due to a blocked path.

* Will this system allow for "Station B" to "hear" the cue tones that are coming from "Station A's" satellite feed in order for "Station B" to insert local commercials?

Thank you in advance for your suggestions!

 

[Kmagrill]

There are a lot of factors potentially involved. For example, what connection methods are available in your market (T1, POTS, ISDN, Public Internet)? Next, how much programming is to be sent over this link? Then you have to decide how reliable it has to be (not how reliable you would like it to be). Then, you must compare cost vs reliability to find the best solution.

 

[frankberry]

Since these are a couple of AM stations, I'll assume that cost is a huge factor.
In that case, I would suggest using the internet. Encode the feeds in some format like MP3 and stream them.
Broadband internet connections are, of course, required at each station.

 

[Robert Bass]

Since these are a couple of AM stations, I'll assume that cost is a huge factor.
In that case, I would suggest using the internet. Encode the feeds in some format like MP3 and stream them.
Broadband internet connections are, of course, required at each station.

Because the OP says cue tones are involved here, I wouldn't suggest using the Internet for this purpose. This method of delivery tends to have delays. Plus depending on what tones are being used, they might get filtered out in the MP3 encoding.

R

 

[WNTIRadio]

Use a Tieline or other similar box to send it via IP on the internet. The cue closures can be sent through the RS-232 and broken out on the other end. There are 4 on the Tieline BridgeIT, for example.

A T1 will probably be very expensive going 35 miles, depending on the provider, tariffs etc.

Internet will be somewhere around $75-100 a month for each end. Be sure to use a QoS router with the Tielines, Telos, Comrex or whatever you use to do it that way.

If you have line of sight between the two towers, have you considered a mono 950 link? If there's a co-located station somewhere in the middle you could use that as a second hop. Not sure of your particulars though, but you said Midwest, so I'm going on no mountain ranges being between the two sites. If it can be done, it may cost a little more up front but there is no monthly expense to the STL.

 

[Lazy J]

Look at the Barix 500 at Barix.com

It's a low cost solution that sends and receives audio via the Internet. They will pass both audio and closures. They are not perfect, but if you can get a good Internet connection on both ends, it will probably be the most "affordable" solution.

 

[everydayguy]

Thanks for your responses -- just to add more info:

We are pretty confident we can get our choice of DSL or cable modem high speed internet at each location...a microwave stl type of link (which would be his first choice) will not work due to some obstructions.

If we can make it work with DSL or cable modem, which system would be most reliable and sound best? He says he might be able to spend up to a couple of thousand $$$ on a solution.

And what about those darn cue tones from the satellite feed? Can Tieline, Comrex or Telos handle that OK?

Much thanks!

 

[Kent T]

Do not use MP3 for broadcast purposes, not multi-generational. If compressed, use MP2, less likely to cause artifacts.

 

[WNTIRadio]

Are the cue tones 25Hz? Or are they separate contact closures that get spit out of the receiver.

Let's get into more detail here:

- What automation system are you using?
- What's the satellite provider/receiver model?
- What's the nature of the "tones"? Audio or closures?

Cable has worked better for me than DSL in most applications, just due to the higher bandwidth available. MP2 at 384k is pretty transparent, especially considering that the bird feed you're getting is most likely 256k MP2.

Go with a Tieline or similar box over the Barix. They handle internet issues much better than the Barix, which just drops lost packets "on the floor" and keeps going.

MP2 will pass the tones. That's what they're coming down to you on the bird with right now.

 

[TomT]

We used the Broadcast Tools DTMF encoders/decoders successfully for routing relays/net work cues from one point to another. However using any kind of internet connection raises timing risks if the tones are sent separately. These boxes appear to have an option to filter out the tones from audio if they are combined. How well this works? I don't know.

 

[Kmagrill]

We used the Broadcast Tools DTMF encoders/decoders successfully for routing relays/net work cues from one point to another. However using any kind of internet connection raises timing risks if the tones are sent separately. These boxes appear to have an option to filter out the tones from audio if they are combined. How well this works? I don't know.

Since it's AM, I assume it's mono. Programs can be transmitted on the left channel and DTMF on the right. Tones will arrive in sync and without being audible. However, if you use one of the products with embedded closures, you won't need to convert the closures to tones in order to transport them, anyway.

 

[kenglish]

Any way you can get a fiber-optic between the two sites...maybe the Cable TV company, or some other service provider?
You could mux a lot of stuff on a fiber, including carrying audio, data, video, l-band RF from the dishes, etc. You could have the dishes at one location, and receivers physically located at each, as needed. Security cameras or alarms could go on there, so one site could monitor for both stations.
Lots'a possibilities. Maybe work a trade-out with the Cable company, too.

 

[Bill981]

My 2¢ worth...
I have two stations about 100 miles apart. The morning show originates in City A, and the afternoon show originates in City B. Both shows are broadcast in both cities. Simian is the automation, with BT 16.4 switchers. Barix Exstreamer 500s in both cities. Simian/BT sends closure to Barix in originating city, and it arrives in sync with the audio at the other end. Actually, the profanity delay in the originating city delays the audio with respect to the closure, but a (TV Term) pre-roll delay is built into the receiving city Simian. Morning A==>B and afternoon B==>A work fine. The circuit is always there, using the public Internet. I'm using the station's normal connection without problems, but a more rural area may benefit from dedicated cable/DSL. Additionally, if you have mono programming, you have two independent bi-directional audio channels.

At another station without dish capabilities I have a set of Barixes (Barii?). One at the originating station, and the other here. No contacts involved because the show is not automated, but the audio has been solid since I put in my own DSL at the originating station.

Since most satellite programming is now on either the XDS, MAX or Wegener platforms, and those receivers deliver relay closures, the Barix will have no problem. The 500 can handle 4 relays in each direction, so sports automation can be done, as well as regular local break starts, rejoin sweepers, etc.

 

[secondchoice]

What about a sat. receiver for the other station? Any local programming to be shared between the two stations, could go over the internet.

 

[Dale H. Cook]

What about a sat. receiver for the other station? Any local programming to be shared between the two stations

The OP wrote "The other station ("Station B") does not have space for a C-band dish."

 

[kenglish]

What about a sat. receiver for the other station? Any local programming to be shared between the two stations

The OP wrote "The other station ("Station B") does not have space for a C-band dish."

That's why I suggested a fiber, with l-band (950-1450 MHz capability). Two receivers, one at each location, with the dish at only one place. All the functions (audio, cues, data) are available at both sites. Also, using a duplex (dual-band) fiber, you can send things both directions.

 

[Grounded Grid]

You'll have to decide for yourself whether compression artifacts are acceptable or not. That's a subjective issue that always generates strong opinions. For many applications, you can use a Barix 500 or Comrex Bric-Link. I have nearly 30 channels running with these boxes. Some are split-channel, as has been discussed here, most use the boxes' contact closure features.

There can be timing issues with the closures, especially if the program provider tends to run a "tight board". However, there are ways to work around this, especially if your Simian software is current version (see "delay execute" macro).

End to end, most of my channels are less than 100 miles and use the same company's DSL network. However, I have one channel that's DSL on one end and cable on the other. An AM station in the general area uses a wireless link and a couple of Barix boxes to feed their transmitter, some 600 feet from their studio building. My most "extreme" case is a program feed that I receive near Seattle, that originates at a station in Los Angeles. They could just as easily be next door. That channel runs on a couple of Bric-Links and includes commercial break triggers. I have several channels feeding AM transmitters, one feeding an FM and one stereo channel that feeds 2 co-located AM stations... one on each side. In one challenging application, I use Barix boxes to move EAS monitor audio around, and I've since learned there are other engineers in my area that are doing the same thing. As long as you accept and address the trade-offs, these things are very flexible and can save you a lot of money over dedicated channels.

Using the contact closures included, feeding tones on a split-stereo channel or taking the tones from your sat receiver & regenerating signals that you can then send to the receiving end are all available options for getting your automation triggers. These boxes also pass RS232, but I haven't tried that yet.

 

[WNTIRadio]

I recommend that you use the Comrex or similar box. The Barixes are fine for non-critical things, but they can drop packets all over the place and have no way to deal with it.

Spend a little more up front, you get FEC, the ability to deal with changing net conditions and more options in codecs.

My only bitch about the Comrex is that it has 1/4" connectors on it. They don't lock like an XLR and can be pulled out by accident. I can't believe they didn't put XLRs on the Bric. No broadcast facility uses 1/4" for anything except headphone jacks these days.

 

[oldiesstation]

Barix uses a proprietary "error camouflaging" algorithm in which it re-plays the last repeated chunk of audio if a block is missing. They are clearly NOT simply dropping the audio and go on - that's what others do. Extended listening tests have shown that the result sounds much better than if you simply drop the packets.
There are alternatives .. mainly, FEC (forward error correction) techniques. But they have a drawback too - they need more bandwidth, and they can only cover specific problems.

 

[WNTIRadio]

Yeah, I know the Barix boxes do that. Have had stations with severe skipping during net congestion in the evening and it's not pretty on the air.

Have one as a backup to a satellite feed. Would like to use it as it sounds better than the bird, except for the way it handles dropouts. It repeats the chunk of audio, but it is still dropping the packets!! There's no resend or any type of error correction, which is necessary for critical audio links over the public internet.

Dumped them for Tieline BridgeIT and have not had any problems.

I wouldn't use a Barix in a critical link. They're good for backup or sending audio around on a private LAN (such as a wireless unlicensed STL link), but I'm wary on a primary public internet link. This particular case was through two cable modems, two different cable systems. Tons of bandwidth between the two, QoS on both routers. Can't control what happens in between.

I'm sure there will be 50 responses from people who never had an issue with a Barix. But this is my experience and am just sharing it.