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Sidestepping A-to-D Convertors For Town Government's Cable TV?
jake-itguy writes "I am the IT guy for a small town municipality. Comcast called me the other day and told me I had to have a digital-to-analog converter for each TV in the municipality, as Comcast is turning off analog cable in September. I did a quick count, and we have 32 TVs across 6 buildings (22 being in the police and fire departments). Most of the TVs are hung on the walls. I told Comcast having a box for each TV was not acceptable and wanted a different solution. Comcast told me there was no other solution." Read on for more details of the situation, and to see if you can offer Jake any advice for distributing cable service within his Indiana town.
jake-itguy continues: "They told me they have been putting these boxes on every TV in each classroom in each school. I laughed when I heard that. I said, 'Do you know how much electricity is going to be needed for each box?' They didn't know the answer. I was bumped up to the next guy in the Comcast hierarchy, who said there was no other solution and I had to pay $3 per month for each box. Being a municipality, we are entitled to free expanded basic cable as a part of the franchise agreement back in 1982.
I know there is a solution, as hospitals and hotels don't have little boxes next their TVs. Unfortunately I haven't found a specific answer to this problem so I am asking Slashdot. Is there a box that can be put in the basement of the town hall that will convert the Comcast signal into a regular digital signal? Most of the TVs in the town have digital tuners per last years a2d conversion of the airwaves. I would be willing to replace the few analog sets with new ones if there is a good solution for this. Each building's cable feed is fed from the town hall. We have a nice big 1-inch cable coming into the building with some splitters coming off the line. Each building gets a 1/2 inch cable. Is there a box that will convert the Comcast signal to analog for the schools? I am sure the schools don't have TVs with digital tuners."
I know there is a solution, as hospitals and hotels don't have little boxes next their TVs. Unfortunately I haven't found a specific answer to this problem so I am asking Slashdot. Is there a box that can be put in the basement of the town hall that will convert the Comcast signal into a regular digital signal? Most of the TVs in the town have digital tuners per last years a2d conversion of the airwaves. I would be willing to replace the few analog sets with new ones if there is a good solution for this. Each building's cable feed is fed from the town hall. We have a nice big 1-inch cable coming into the building with some splitters coming off the line. Each building gets a 1/2 inch cable. Is there a box that will convert the Comcast signal to analog for the schools? I am sure the schools don't have TVs with digital tuners."
Hotels frequently have a bank of converters, each tuned to a different digital channel. The outputs of all of the converter boxes are put onto separate analog channels, multiplexed and fed through a distribution amplifier.
You would need a box for each channel you wish to receive. While this may work with a hotel where they own all of the premise wiring to the rooms it would be impractical for a widespread system across a city.
Tisha Hayes
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It does the digital to analog conversion in one spot, and is used to handle doing so for large buildings such as hospitals or apartment blocks.
If you use haft-inch and one inch do describe coax cables maybe your not the best guy for the job.
Half inch, 1 inch, and "625" (which stands for 0.625", or 5/8 inch) are all industry-standard ways to specify the different sizes of 75 Ohm CATV coax Mr. anonymous dumbass. Yes, I am a CATV engineer.
Better advice: sue. The FCC is requiring cable providers to maintain analog cable until 2012 unless they provide converters for their customers. Unless I'm misunderstanding, charging their customers to rent the boxes was NOT one of their options.
Check out my sci-fi/humor trilogy at PatriotsBooks.
If the franchise agreement really says you get expanded basic in exchange for them getting the franchise, then I'd have a word with the township's lawyers. Depending on how the deal is stated, it's probably Comcast's problem to make this work, not yours. I suspect that if the town's lawyers had a word with Comcast's lawyers, then someone in Comcast's engineering department would sort things out right quick.
A thousand pounds of wood moving at 300 feet per minute. Don't get in the way.
U.S. digital cable is not ATSC (8-VSB modulation) over-the-air broadcast signal compatible. Instead, the main MPEG2 payload is carried in 64-QAM or 256-QAM modulation, within RF channels that fit the usual US-standard 6 MHz spacing. Alongside this, are one or more "out-of-band" carriers that use a different modulation format and lower data rate, that carry channel maps and other administrative information. Finally, there is an upstream (settop box to head-end) channel in RF bands lower in frequency than the downstream RF, that is used for administrative purposes and for pay-per-view.
The signal structures are described in published standards freely available from SCTE. The out-of-band and reverse channels have two different standards, reflecting the original developments by General Instrument (now Motorola) of one standard, and by Scientific Atlanta (now Cisco) of the other.
Much (but not all) of the content is covered by "conditional access" (encryption), the details of which are of course unpublished.
I actually work for a TV company... might be able to give a little insight.
Most headends for hotels, hospitals and the like are comprised of a rack of STBs, each tuned to a specific channel. The output is modulated as an RF signal and combined with all the others, so the incoming digital signal is effectively converted to analog for redistribution on the local coax network.
So, if you're wanting to display more than 32 services, you'll need at least that many STBs at your analog headend. You'll also need to manage the infrastructure to distribute it to the six buildings, which would probably mean running underground cables underground, and if there is any sort of distance you'd need some RF amplifiers. You might be able to get around some of that using something like a slingbox over IP, but again, added cost.
Finally, there's the management aspect. What happens if a channel moves to another channel number? You'll have to retune the box. If a box goes down for any reason, you'll have to replace it as the channel will be knocked out. And one of the less fun aspects of managing a TV system is that people treat it as a utility... if it's down, expect to get a call, even at 3AM.
If I were you, I'd push your cable company to donate STBs in order to keep your relationship rosy. That way, no $3/month fee (which does seem wrong based on your agreement), and none of the buildout/management headaches.
Best of luck.
Still not dead.
This is how we offer TV service to our dorms.
We have 1 box per 2 channels of directTV (or dishnetwork I can't recall which). Each one pushes out to a tv channel that their TV can tune in to watch.
We offer 30 channels so we have 15 boxes.
First, disclaimers. I don't work for Comcast, but I do consult to them. I don't speak for Comcast in any way. I am under NDA, so I can't give you the sort of specific technical information you need. There may be any number of reasons why this thing wouldn't work in your circumstances, or why Comcast wouldn't choose to provide you one.
Having said all of that, you might want to look into the MDTA. It's the "solution" you're sure exists ;-)
It is POSSIBLE that one of these could be connected to your 1 inch (probably 850) hardline. But be aware that it doesn't mix with digital video services, though CableModems and MTAs work fine when hung off of it.
-Peter