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Another 9News Question...HELP

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Ryfly

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#1
So i got the frequencies that 9 News uses to talk to each other as well as the traffic reporters.

But i was wondering if anyone knew what 9News uses to talk to the anchors etc. So when 9News goes live to Sky9 and the anchors talk to the Sky9Reporter, are they talking on a Frequency ? Or is it on some other type of system? Like a Digital Video system etc.

Any info on this be awesome!
 
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#2
The technical term for what you are asking about is IFB for Interruptible Feed Back. It is used to pass program audio and to also provide cues to the talent. It was at one time on an RF feed. Channel 9 used 170.15. Channel 7 had something on VHF as well. They all use dial up IFB now or just use air audio for hearing the talent in the studio without the director's cues. Satellite live shots have to dial up IFB because they are out of range of the metro area. Satellite live shots have the added fun of dealing with the delay of getting the signal to the satellite and then back to earth, a 44,000 mile round trip. The audio in the ear piece the reporter has needs to be mix minus, the audio of the station minus his audio. You will sometimes see a reporter yank the ear piece out when the mix is wrong because he hears himself seconds later and it gets confusing.
Scan between 450 and 451 there is lots of channels in there that have program audio, data transmissions for controling transmit equipment and news desk communications as well as engineering crews.
 

RFsponge

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#3
Behind the scenes

Two different lines of communication are in use when the copter is on the air. One from the ground to the copter, one from the copter to the ground. That configuration changes when the helicopter's transmitter is turned off.

The anchors, when on the air, are broadcast for all the world to see and hear from their transmitter on Lookout. That signal is simulcast on a company frequency, picked up by the copter and refered to as what is known in the industry as IFB. Interruptable Feed-Back. Interruptable meaning that a show producer or someone else behind-the-scenes can interrupt the simulcast and talk to the copter crew on that frequency. That's the line of communication from the ground to the copter. When it's time for the anchors to talk to the copter, all the copter crew is doing is listening to the same broadcast that everyone else hears.

The helicopter is constantly transmitting a microwave signal carrying audio and video back to the station. That is the line of communication from the copter to the ground. The reporter is using the same microphone that she uses on-air. At the proper time, the control room simply puts that microwave signal on TV.

So you've got the station talking to the copter via IFB, and the copter talking to the station on microwave. Which, for your monitoring purposes, means you'll only hear the station's side of the conversation. For example:

Producer on IFB: "Thirty seconds. copter."
Copter on microwave: "Copy. Thirty seconds."

Thirty seconds later: Anchor on TV and simulcast on IFB (but no-one in interrupting the simulcast signal) "...Let's get a birds-eye view from the copter. Jane, tell us what you see."

Copter on microwave with signal now on TV for the world to see: "Quite shocking Dick. It appears Boulder City Hall is collapsing under the sheer weight of the hubris and hipocracy contained within the heads of those inside. There is no hope for the structure, but crews are working desprately to enlarge the doorways so those with extremely large heads can escape before the building sinks to the center of the planet..."

(Hey- I can dream, can't I?)

Also, there is probably some time-based compensation built into the IFB signal because of delays in digital signal processing from the copter's transmitter to the station and then out to the transmitter on Lookout. Usually one or two seconds. (When that signal gets pumped through places like Comcast's or Direct TV's systems, there can be as much as a 18-second delay from image aquisition to your TV set.)

When the copter's transmitter is turned off, both station and copter switch to another company frequency and talk "normally." At that point, you'll of course hear both sides of the conversation. When it's time to go back on television, the microwave is powered up and the crew monitors the IFB frequency.
 
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Ryfly

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#7
ok,

so the helicopter listens just to the standard analog broadcast from the Station that everyone else is hearing thru there tv's and then Sky9 is constantly broadcasting to 9News on a certain frequency. And then they make sure that in the ear piece they mic out the sky9 reports so she doesn't hear herself. Is that right?

So is IFB on satellite feed, a encoded audio transmission to talk to 9News? How would i be able to hear Sky9 talk to the anchors? Do they have another frequency to do the news audio on?
 
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#9
They use the digital microwave channel on 2 Ghz to the autotracker on Lookout that is relayed by STL (Studio to transmiter link) return to the studio. Or they use 450.6125 on the two way radio to talk back. It can be very complicated.
 

RFsponge

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#10
...and the only thing I'll add is that the IFB frequency is most likely a simplex UHF frequency, not encoded in any way, is probably broadcast from Lookout with decent wattage, and should be in the media band. 450 - 451 MHz. I don't know that for a fact because I don't work for channel 9. Just scan the band at news time and listen for their air signal. It should be interrupted from time-to-time by someone behind-the-scenes.

As far as monitoring the microwave signal to or from Lookout with your police scanner, forget it.

And you are correct. The air signal will be muted when the reporter in the copter is talking on-air. That way she dosen't her herself in her ear with a one or two second delay...

OK. So that's like... THREE things...
 
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#11
This is an interesting topic which I am still not quite comprehending. If you could dumb it down for me and others I would appreciate. Subtract out what there is no hope of hearing and put down what we can. Example:

Constant webfeed for KDVR - http://mfile.akamai.com/25243/live/reflector:22207.asx?prop=n

Constant webfeed for 9news - mms://a1920.l2234159919.c22341.g.lm.akamaistream.net/d/1920/22341/v0001/reflector:59919

Thanks a bunch!
 

RFsponge

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#12
I failed to consider the raw microwave feeds that stations put up on the web. Good point.

As far as monitoring behind-the-scenes activities, I recommend consulting this part of the DB:

http://www.radioreference.com/apps/db/?aid=4136 Sometimes very entertaining.

It looks like Channel 31's operations are outside the media band, but still easily scannable. IFB frequencies are identified as such...
 
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#13
That's more like it. Thanks a bunch. And for geeks like me those feeds are very useful when I plug them in to custom channels at orb.com. I can pull up the KDVR feed and most of the time it is the live CDOT webcams on a cycle on my power vision phone. Not the crappy stills that CDOT puts on their website. I would still love to know how the media outlets tap in to CDOTS cameras. If it's through microwave as you've mentioned then the general public would probably still be SOL, but if it through the internet I would love to get my hands on those links.
 

RFsponge

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#14
The CDOT network is mostly fiber-optic, with a little bit of microwave sprinkled in. At the point where all the images are gathered, all the stations chipped in to purchase a distribution system (a "router" is the more technical term) to get the desired signals from that point (the old TC building at 6th and Wadsworth) to the TV stations. It's all microwave from from there...

Well, that's as clear as mud, isn't it? Let's try this:

All the signals from CDOT's cameras, statewide, go to 6th and Wadsworth via mostly fiber.

From there, the stations pick whatever camera they want to put on TV and route that camera's signal to their systems via microwave.

I'm not an engineer, so I'm probably leaving something out, but i know this is the basic structure of the system.

Rob

PS. I should also mention that CDOT makes a lot of their cameras available on their own website, but you're right. They're mostly stills. I would imagine due to bandwidth restrictions...

http://www.cotrip.org/atis/web.ZoomboxMarshal?device=CCTV&Zoombox=0
 
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#15
bandwidth smandwith. If Caltrans can set up spectacular streaming video like the ones at http://www.dot.ca.gov/dist4/realtime.htm then CDOT could do it. They just want to be greedy. Tell me that more people would tap in to the bandwith on CDOTS then Caltrans. CDOT is just behind on the times out here. They prove it every time they expand a highway just enough to ease congestion, but never consider future growth so in a couple years they have the same problem. Chasing their tails. Don't get me started on that though. http://cad.chp.ca.gov/ is yet another way they are way ahead of us. Jim does a great job with his alerts, but there's nothing like real time.
 
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#17
wozz said:
CDOT doesn't want to be greedy. They don't have the money to be greedy. TABOR supporters want to be greedy. Blame them.
I would just add to that, California has always had all the bells and whistles. They also have the shakiest fiscal health of any state in the nation. We may be bumpkins here in Colorado with clogged roadways and crumbling infrastructure but a lot of that is due to Californians escaping to here from the mess they created there. 'Nuff said because anything else would be way off topic. Or more way off topic.
 
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