I am putting a lot of effort into this next tutorial which is all about Fiber Optics for Broadcast. But it is taking much longer than usual as I have high hopes to make this a really great tutorial. In the mean time while I work on it here is a sneak preview.
The sound effect were added later, fusion splicers don’t really sound like that, but it seemed like a fun thing to do.
Working on a project that uses IP radios to transmit HD-SDI over IP. These radios are from Exalt and can work at upto 1Gb/s. The great thing is that we can monitor and control both ends via a Web GUI. I was sitting up in the office looking at the data rate and received signal levels of both the local and remote transceivers. We have some alignment to do on the dishes as the received levels are too low, I think we may be on a lobe and not the main beam. Plan to fix that tomorrow.
Soon we will be running loads of RG-11 around the tower for another project and I had one of the guys cut off eight pieces 10 feet long. This is so we can see how they will work when we have to instal then into a rack. Eight cables of RG-11 don’t bend very easily so we need to know if it will work before the guys have run a couple of hundred feet to a room and find it don’t fit.
We are putting in a couple of new waring systems to alert personnel to unusual conditions. We have built the two of them inside one box and they share a common power supply of 12 volts. Each is operated by a 12 volt relay but we have also installed a manual bypass so we can turn the lights on by hand.
The lights are installed all around the building and in the parking lot. Each is wired as a home run back to the terminal blocks and is fused independently. That way a short in any one line will not take the system down.
Some of the lights are the ones you saw on this blog flashing not too long ago while the others are smaller version.
We will complete it when I get back from NAB.
The wiring project it moving along with Fiber Optic cable being installed we’re almost done. Here you can see the yellow armored F/O cable being run to the trays where the armor is striped off and clamped to the tray.
Here are the F/O trays
Here’s the tools that Bill was using to install the F/O
The hammer is really useful with Fiber
The resisters are under the light pipes on the left
Those little IP I/O boxes I have been testing are working like a charm. I have four of them in my office to test, one is the master turning on relays in three others. The plan is to have the remote boxes switch 24 volts to turn on warning lights and to feed back to the same boxes input, that one will go to a fifth box that will show the remote box has 24 volts and switched. Pretty cool.
Normally the inputs just require a contact closure but they will take in up to 30 volts. To do this I need to cut out the pull up resisters.
They come from Data Probe.
The other day a fellow engineer was sharing his thoughts on media files used in broadcasting and his station in particular, he was ranting. His station has logo inserters and the guy who does all the artwork for them can’t seem to keep straight that what looks good at 700 by 700 pixels may not look good at 40 by 40 pixels. He says it always take the guy about three try’s before the logo looks good.
Then when they want a new News open or some other motion graphic they always get the wrong file format from their creative service’s guy. When they complain that it’s the wrong format this guys says “it’s 1920 by 1080 60I, what do you want?” and they have to tell him, again, that their servers need it in MPEG2 format, not AVI.
With servers just a few years old the types of file formats they can accept is not upto date, and even the latest video server that does accept more formats still has to be made compatible with the older ones so files can be shared across all the servers they have. He told of the head Mucky Muck up in corporate stating that all video submitted for air must follow his standards for frame sized and file format. Well the advertisers had their own ideas and continued to provide whatever format was convenient to them, their paying the money so you convert, seems to be their motto. Then theres the shows that arrive in various formats and need to be converted before air and this falls to the engineering department since they seem to be the only ones who understand what is required.
My friend longed for the days of NTSC, where there was only one true format. You could manipulate any file you wanted within your graphics box or NLE but everyone knew that the final output had to be, NTSC.
NTSC is dead, long may we pull our hair out over the wrong file or frame format.
Fiber in - SDI out
One of our clients has setup a studio / control room of their own. Up until now we had to run their server and sat feed because there was no link between them and us at the transmitter. Now AT&T via The Switch (thanks Linda) has put in an SDI F/O link from our clients’s place in the heart of the city to the transmitter. When we get our stuff together we’ll have it moved to our studio.
So, the AT&T guy shows up and does our end, which is in our telco room right where the
Telco Room Patch to my TX
interconnect system the guys and I have been working on is. All I have to do is put in a 12 foot cable from the F/O RX to the patch panel that goes to my room and then connect the TX room panel to my SDI monitor.
TX end of it
Much to my surprise it work, just kidding, Marty and Bill have done a great job. I thought it was appropriate that my station was the first to use this new interconnect system.
Now for this first test AT&T sent us color bars and when I punch it up I see that it’s 1080 / 50I. 50 frames, where are they getting this from, France? Well it worked just fine and the next day our client had a feed for us. But is was just black SD-SDI. Good thing the monitor displays the format. I switched it over to 
crosshatch so I could see the embedded audio in the horizontal blanking. I had them pull the feed a couple of times to be sure it was them. It was.
These new F/O receivers AT&T are using hold up to 4 RX but have no provision for audio, the tech says you can get it as an option.
So for this project I am working on I need to control the Flashing Lights via IP and I found these boxes made by Data Probe called IP IO-8 that connect to an Ethernet network and have 8 relays and 8 inputs that you can control and monitor via a browser interface. Now thats pretty cool but the really cool thing is that they can talk to one another, so a contact closure on box A will cause a relay on box B to close, or open, what ever you like. One input can control several remote boxes and thats how I’m using them.
In the video look to the right and you can see me clicking the on screen buttons causing the relays to close and open, the boxes have LEDs that show the status of the relay.
So here is a little video of my first time trying out one of these boxes. I’ll have more later as the project evolves.
ZWP F/O from Commscope
We are nearly ready to start pulling the Fiber Optic cable around the tower building. Ours is an armored cable with 12 strands that will run from 18 points back to the Telco room. But Paul brought in a F/O cable that Astound was installing at his station, it to carries 12 strands and it has an aluminum jacket. The big deal about this cable is it’s bend radius. Our F/O cable has a bend radius of 18 inches, this one is 5 inches, that makes for a much easier install.
We opened up this new F/O cable to see it’s strands, we could see they where
Smaller fiber
much smaller/thinner than the one’s in the cable we are using. These are both Commscope cables the new one is their ZWP or Zereo Water Peak that has a smooth attenuation responce.
Comparing Fiber sizes
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