: OTA For A Condo or Building: MATV


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stampeder
2007-04-21, 09:21 PM
You mean a "UHF only" antenna, right? :)

roger1818
2007-04-21, 10:51 PM
In Montreal not only will you need a UHF antenna but you also need a good VHF antenna (cut channel yaggi?) to pick up WVNY-DT on 13.

bobbonet
2007-04-21, 11:36 PM
Yes I meant UHF...

The sales rep said that with the UHF "channelmaster" you can catch channel 13... I said are you sure, and he said yes.

We shall see, I will speak with the owner on monday and see what he says.

Later

roger1818
2007-04-22, 09:06 AM
He is correct that the CM 4228 is not only an excellent UHF antenna, but it will also receive the VHF-HI channels (7-13) reasonably well. However, from what I have read (see the Montreal Reception Results forums) you need a very good antenna to receive WVNY-DT in Montreal. Does the sales rep you are talking to have experience with the 4228 in Montreal?

bobbonet
2007-04-23, 10:20 AM
I will let everyone know how the reception is. As this will go on top of a 5 story building, it should be better than most people in the montreal area who put it on their roofs.

Another thing, which maybe some of you know is that the system installed will only work with expressvu and residents can have expressvu and OTA channels at the same time.

However the same is not true about Cable (videotron) as they share the same frequencies as OTA and will not mix.

Thanks,
Roberto

Tony Maselli
2007-08-01, 09:39 AM
Okay, so I live in Southern Ontario and I operate a headend at a University. Currently I have the Winegard log periodic antenna, the CM4228 antenna and a bunch more cut to frequency antennas. So I'm using the 4228 and the winegard for my OTA digital channels. I have 1 pointing towards Buffalo and the other pointing towards Toronto. I combine both antennas into 1 output and I input that into my Fuji ATSC tuner card installed in my P.C. When I do a channel scan it's searching for channels starting in the Broadcast frequency range and going all the way up to channel 66 broadcast frequency. That's fine and dandy if all I wanted to do is view it on my P.C. but this is my issue. ................ I would like to distribute this onto my Cable T.V. netowrk across campus. Now if everyone had a broadcast frequency ATSC tuner I could just keep the current channels I pull in on the same frequency but because I'm down converting the signal from it's originating broadcast frequency (let's say 43-1, 43-2, 43-3) and than doing an upconversion to a cable frequency (let's say channel 65 cable frequency) my tuner is not able to pick it up cause it's searching for channels in the broadcast frequency range. Is there a tuner that is capable of doing both or one or the other? ....... and I'm not talking about QAM here ...that's not even in the equation.

99gecko
2007-08-01, 11:34 AM
Welcome Tony Maselli

You obviously know a lot about terrestrial signal distribution. I hope you realize that we have an entire forum here dedicated to off-air digital tv. You will find it here:
Over-The-Air (OTA) Digital Television (http://www.digitalhome.ca/forum/forumdisplay.php?f=81).
Although the industry uses the term "off-air", it is commonly called OTA by end users (DHC) to avoid confusion - a station that is called "off-air" to the layperson might be confused with a the station is not transmitting; as in "off the air". I encourage you to browse through and specifically read stampeder's Knowledge Base, although I suspect you are already quite familiar with the most of the content.

Firstly, I assume you have the proper equipment in use, or ready to use, to prevent signal leakage of the campus's own distributed signals out of your antenna array. Industry Canada frowns upon this.

Secondly, since you are already distributing signals, I am assuming you are aware of the legal ramifications of operating a Master Antenna Television System. If not, you should query the university's Legal Dept. Here is a thread that recently dealt with a condo resident wanting to install MATV system, in their building.
Installing OTA For A Condo: MATV & Legal Info (http://www.digitalhome.ca/forum/showthread.php?t=57242)
Specifically look at the legal issues start around post #20. There are issues that could make such an array considered a BDU, and therefore subject to Must-Carries, and honour Simultaneous-Substitution regs. Please note that there are exceptions and that one of them includes educational institutions. However you might have to prove that all distribution nodes/points qualify under this requirement.

To your specific questions:
I can only guess that your best answer will come from querying Head-end equipment manufacturers. This might be out of the scope of end user equipment.
If I could hazard a guess as to what is happening... What you are needing to do is modify/blank/overwrite the existing broadcaster's PSIP data stream if your are retaining the ATSC encoding. Did you mean you are down converting HD formats to SD, but retaining the ATSC encoding? If this is the case I think you will find you have to convert the signal to NTSC. However, I think this is what you meant since you indicated most of the residences do not have ATSC tuners. If you are positive that this is happening because of the down conversion, then I'm not sure why a simple NTSC tuner card in your PC wouldn't be able to detect your added signals. Perhaps a second tuner (NTSC) is in order for your PC. Most ATSC tuners (whether they are PC, integrated, or STB) cannot simultaneously detect NTSC and ATSC signals, (if they can even demodulate NTSC). It is one, or the other. There are lots of NTSC tuner cards on the market and several that do ATSC and NTSC. However, I have never seen one that does both at the same time.

I'm not sure I answered your question, but please reply with your comments. Posting your future questions in the OTA forum will help, since more eyes will see it.

EDIT: By the way, we would love to know details about any difficulties you experienced due to phase shift because of two different types of antennas and how you overcame it. As well, tell us more about your rig - Is it on a tower?

JohnnyG
2007-08-01, 01:55 PM
I'm confused....are you trying to remodulate the ATSC signal to a different frequency, or are you trying to decode and insert the *analog* video into your cable system?

99gecko
2007-08-01, 02:38 PM
JohnnyG,
That's what confused me too. I still think he needs a head-end advice, since it is multi-channel solution. A typical ATSC tuner can only tune one channel of bandwidth at a time, but maybe he is already doing this??

Tony Maselli
2007-08-01, 02:45 PM
Okay, my rig ........ Well, I have about 48 BEV receivers going up to 3 dishes. I have approx. 12 cut to frequency antennas for my OTA analog channels. I have a BUD C band dish that pulls in HBO.

I recently installed 2 broadband antennas for my OTA digital channels. I take both ouputs of the antennas put them into a splitter, take the combined output and put that into a 20dB broadband amplifier. (Incidentally I have mast mounted pre-amps for my broadband antennas also). Take the output of the amplifier and put that into an 8 way 20dB tap. So now I have 8 ouputs that I put into 8 seperate Digital Down Converters (DDC). Dial in the frequecy of the digital station on the DDC (eg. Ch43 PBS) and than take the output of that and put that into 8 Digital Up Converters (DUC). Dial in the Broadcast Frequency I want my ATSC receiver to find it on, on the DUC ( eg. Ch 27 Broadcast). Take the output of that and plug it into a 16 Port combiner. And this I do for every channel (or output) I take off of my 8 port tap. My 16 port combiner goes to a 8 port combiner which than goes out onto my cable system. ......... did I confuse you yet?

As for the regulations regarding MATV systems ............. because we don't charge for our services and we are a private University than we do not fall into that jurisdiction.

99gecko
2007-08-01, 03:50 PM
Tony, I suspect there might be PSIP conflict.

You are more qualified than I am, but this is what I figure might be happening....

What is happening to the PSIP data during the down-up? If it is not removed the end-user ATSC tuner will be looking at that to build its Virtual Channel Table which will be wrong since you've assigned it a new frequency. If it is removed, the tuner will not know how to decode the channel as the channel map will be missing.

Try looking into this at:
www.ATSC.org
www.psip.org

edit: I am also confused about this part:I'm down converting the signal from it's originating broadcast frequency (let's say 43-1, 43-2, 43-3) and than doing an upconversion to a cable frequency (let's say channel 65 cable frequency)
Does this conflict with this statement, since as you know the frequency charts are different between broadcast and HRC :
Dial in the Broadcast Frequency I want my ATSC receiver to find it on, on the DUC ( eg. Ch 27 Broadcast)

let us know how it goes.

jrf28
2007-08-01, 04:37 PM
There are some tuners that will tune to ATSC channels placed into cable bandplan channels, but most consumer TVs and such won't... do you want everyone to be able to see the channels?

If so, the cheapest solution is probably to set the output of the DUCs to channels 2-13, as the cable and broadcast bandplans overlap, but that would require moving channels I would assume.

Another thing that MIGHT work is (depending on your infrastructure as you get getting up there in frequencies) is to set the DUCs to a channel in the broadcast bandplan above the end of your cable channels, for instance you have cable channels up to 59, you haven't even reached broadcast 14... but that just seems like such a bad idea.

I don't think the 8VSB to QAM transcoders are that expensive (maybe $2500--also usually would allow you to take data streams of 2 8VSB channels and put them into 1 256QAM channel to save bandwidth), but I assume your budget is very tight.

JohnnyG
2007-08-02, 09:39 AM
If I'm following you correctly, what you need it an ATSC remodulator. If you or anybody there is an IEEE member, look here:

http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=713200&isnumber=15451

Tony Maselli
2007-08-02, 10:52 AM
Yes, I would like everyone to be able to see the channels on the frequency that I place them on using the DUC. However, I'm restricted with bandwith cause my plant only goes up to 550Mhz. The DUC's won't allow me to place the new channels on CH2-13. Instead I chose to use the broadcast CH 14-27........... why 27, because that's the end of my frequency spectrum that I'm capable of going up to. It's really not that bad of an idea, and seeing that most students aren't aware that the ATSC receivers come in 2 different flavours ( i.e. cable bandplan channels and broadcast banplan channels ) I have to side with the majority that is out there. I myself amd having a difficult time finding a receiver that does the OTA cable bandplan channels. Short of going over to the States and buying one I'm left with the only other option than to offer these Digital OTA channels at the end of the cable bandplan channel line-up making sure not to go over my bandwidth restriction.

QAM .......... well, I'm sure I could go this route, but I'm left with the daunting task of aquiring a bunch of STB's which isn't financially or econimically feazable. I wouldn't want to go with something that is dated and that might eventually be uilt into the set itself ..... atleast not until it becomes a standard, which I don't see it doing for some time.

Cost wise 8VSB is the way I'm going for now, besides ....... this is just a pilot project for now and we might be scraping it for IPTV in the future.

JohnnyG
2007-08-02, 12:41 PM
What up/down converters are you using, exactly?

Tony Maselli
2007-08-02, 01:07 PM
DDC864 Digital Signal Downconverter
DUC864 Digital Signal Upconverter (54-860 MHz)

JohnnyG
2007-08-02, 02:16 PM
I looked over Drake's documentation and I don't see any restrictions indicated for channel 2-13 output. What issue are you facing with this?

Although this solution should work, I'm pretty sure there are units on the market that do nothing but remodulate the RF signal to a different channel without the down/up conversion that these modules do. It doesn't seem like you need to take the signal to baseband, but perhaps you have other things in mind.

I would suggest calling Drake and just asking them!

Tony Maselli
2007-08-02, 02:56 PM
You're right, I don't have to take the signal to baseband and I could just take the raw baseband signal and input it into the combiner without the down and up conversions ..... however You aslo have to keep in mind that it is going through 2 sets of combiner with a total through loss of approx. 24 db. Sorry, I forgot to mention that this is the reason I'm going through modulators ....... is because I also have to boost the signal before it goes into the Make Cable Output feed to all the students. You have to balance all your modulator outputs when you go into each 16 port combiner. It's a tricky juggling act, but with a little patience it pays off.

I've been in consulatation with Drake and he told me I could either use a terrestrial ATSC baseband receiver or a terrestrial ATSC cable receiver. Keeping in mind that both of these are receiving in 8VSB.

As far as using 2-13 .... I haven't tried it yet, but I will let you know how that goes ..... but I don't think I want to re-invent my whole cable channel line-up right now!! We'll see, if I make some progress with this.

borgninee
2007-08-24, 10:15 PM
Hello everyone, I'd appreciate some advice, especially from bobbonet. I've just moved into a new condo with around 200 units.

See this post for details:

http://www.digitalhome.ca/forum/showpost.php?p=591339&postcount=318

I'd like to approach the board about installing OTA through the satellite system and am wondering how much it would cost. I think the costs are

- antenna and mount, $ hundreds
- amplifier $ hundreds?
- filters for each unit $ 10 per unit?
- installation $ hundreds ?

Thanks a lot.

stampeder
2007-08-27, 09:36 PM
Tony, I've relocated this thread into the OTA Forum where we can generate more response for you. I'll look through this thread and respond when I have time, but there are several more of us who have experience in this area and can offer further advice. See the other MATV threads here in the OTA Forum too.

cheers,
stampeder