MATV Systems and the Digital Transition - Page 9 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #241 of 251 Old 12-05-2008, 07:34 PM
Member
 
OWENF's Avatar
 
Join Date: Apr 2007
Location: bucks county
Posts: 71
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
AntAlt Mike:
I got some serious homework to do.
LG,Pro:Idiom
I can deal with passing the HD locals but the other content is just way to much $.
Regards
Owenf
OWENF is offline  
Sponsored Links
Advertisement
 
post #242 of 251 Old 12-05-2008, 07:49 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,564
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Liked: 25
DirecTV has made a deal with something or someone called Pro-idiom that lets them remove the DirecTV encryption and replace it with Pro idiom encryption and to then distribute it in QAM format in the cable TV channel plan.

LG makes hotel TVs that accept a Pro idiom module, which is like accepting a cable card that can decode DirecTV. That enables any LG TV with a pro idiom module in it to decode any subscribed to DirecTV programs, and since all major markets have anywhere from four to eight broadcast HDTV stations available on DirecTV, that will be enough local broadcast HDTV to meet the needs of most hotels.
AntAltMike is offline  
post #243 of 251 Old 01-02-2011, 12:24 PM
Member
 
fredd's Avatar
 
Join Date: Dec 2003
Location: New Jersey
Posts: 83
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I am resurrecting this thread because I'm curious if anything has changed regarding the upgrading of older pre-digital MATV systems over the last two years. The reason I'm asking is a relative of mine recently moved into a senior citizen housing building which houses many residents who are basically living on social security or fixed income budgets and who can't afford cable service. When the analogs went dark last year the management arranged for Comcast to wire the site, essentially abandoning the existing MATV system in place and recommended everyone subscribe to cable, but for many residents this was not an option. The roof antennas are two Hi/Lo VHF and one corner reflector UHF Yagi which appear to be in good shape. Being only 20 miles from the ESB transmitter with LOS reception (per TVFool) I don't see why they can't receive all the digital stations on their MATV system, but the only thing coming through is their CCTV feed from the lobby of the building and 1 PBS station located about 10 miles southwest. Re-orienting the antennas east to the ESB transmitter (some genius pointed them due west) might improve things, but after reading all 9 pages of this thread I'm thinking that the headend and distribution-amp system might still be a problem too. Is there a good inexpensive broadband distribution amp on the market that could supply five trunk lines feeding 125 units? My thought is to just bypass the existing headend and distribution amps (assuming they're VHF only - I'm going up to take a look at the setup this week), and distribute the OTA signal directly. Residents with newer TVs would be able to tune-in directly and people with older analog sets could get a converter box -anyone know a cheap source of these?
fredd is offline  
post #244 of 251 Old 01-02-2011, 12:41 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,564
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Liked: 25
I once installed a broadcast MATV system at a senior living community about 30 miles from NYC, and while I no longer service that building, it is part of a chain with whom I continue to enjoy business relations. Unfortunately, it doesn't seem to be "you" because they had one trunkline.

If your wiring is intact, then it is often feasible to install an on-channel broadcast DTV system, but first, one would have to make a preliminary investigation of the wiring, just to make sure there aren't a lot of taps that are not capable of handling UHF frequencies.

If there is no frequency impediment to on-channel distribution, then I'd have to estimate the relative signal levels to see how much pre-filering and balancing might need to be done to keep the distribution reliable.

If you existing system was primitive enough, it should still be passing channels 7, 11, and 13, but if it used SAW filtered processors or modulator/demodulator pairs, then it wouldn't.

PM me more information and I'll see what I might be able to do for you., and post your www.tvfool.com plot, so we can better estimate your likely signal level differentials.
AntAltMike is offline  
post #245 of 251 Old 01-02-2011, 01:12 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,564
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Liked: 25
I just did a TVFool analysis for the center of Union, NJ, which is 17 miles west of the Empire State Building, and the calculated signal power levels look manageable. You'd need a separate, filtered antenna input for New Jersey PBS, and you'd benefit from having someone with a spectrum analyzer set up a PFA-6600 programmable filter amplifier unit.
AntAltMike is offline  
post #246 of 251 Old 01-02-2011, 01:56 PM
Member
 
fredd's Avatar
 
Join Date: Dec 2003
Location: New Jersey
Posts: 83
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Mike, thanks for the input, I wasn't sure anyone would look at this "dusty" thread again. The cabling is RG-59 and the room taps are 300 ohm twin lead screw-downs which appear to be fed with a simple LC cap&coil off the cable (for impedance matching? freq. cutoff?). I'll know more about the distribution later this week. here's the TVfool plots:
LL
fredd is offline  
post #247 of 251 Old 01-02-2011, 03:11 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,564
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Liked: 25
Those taps are to bleed off a small amount of the signal and pass the rest through. All of those 300 ohm taps I have seen were rated to old channel 83, which is 890 MHz, and well abouve the 698MHz upper limit of broadcast UHF (channel 51).

Unfortunately, they leak like sieves, so on channel signal distribution would be subject to "ingress interference". You might find that your local channels 2, 4, 6, 7, 9, 11 and 13 had been electronically shifted to channels 2, 4, 6, 8, 10 12 and oif you have all seven, then one might have been shifted to a "midband channel from 14-21, since those channels are actually at frequencies between channels 6 and 7 to avoid ingress interference.

Who owns the place? Is it part of a chain?
AntAltMike is offline  
post #248 of 251 Old 01-02-2011, 05:14 PM
Member
 
fredd's Avatar
 
Join Date: Dec 2003
Location: New Jersey
Posts: 83
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Not sure who owns the building, either the county or township but I'm fairly sure it's got some federal subsidy too.

I'm wondering if replacing the 300 ohm taps with 75 ohm would be worthwhile?
fredd is offline  
post #249 of 251 Old 04-19-2011, 11:19 AM - Thread Starter
AVS Special Member
 
kenglish's Avatar
 
Join Date: Jan 2000
Location: Salt Lake City, UT, USA
Posts: 5,392
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked: 31
Got some info from Johansson the other day:

"Profiler: Programmable filter-amplifier:
We will present some new products in the well-known Profiler' range. The new profilers are built on a completely new platform and are commercialized as Profiler PLUS' and Super Profiler'. These products are fully prepared for the (European) analog switch-off. They have even more UHF-inputs, combined with highly selective filters. The increased selectivity is made possible thanks to a new filter technology, developed by Unitron. The Super Profilers have 2 super-selective filters, with an impressive rejection of 30 dB at only 1 MHz! They also have a frequency conversion function, enabling the user to shift a multiplex to another frequency, so he can really manage his own frequency plan!"

These new products are to be unveiled at the ANGA Cable show in Cologne next month. They promise to send details then.

http://www.johansson.be/en/welcome.html

Ken English, Sr. Engineer, KSL-TV.
"The postings on this site are my own and don't necessarily represent the Company positions, strategies or opinions."
kenglish is offline  
post #250 of 251 Old 04-19-2011, 01:52 PM
AVS Special Member
 
AntAltMike's Avatar
 
Join Date: Nov 2001
Location: College Park, MD
Posts: 3,564
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Liked: 25
Quote:
Originally Posted by kenglish View Post
Got some info from Johansson the other day:

"Profiler: Programmable filter-amplifier:
We will present some new products in the well-known Profiler' range. The new profilers are built on a completely new platform and are commercialized as Profiler PLUS' and Super Profiler'. These products are fully prepared for the (European) analog switch-off. They have even more UHF-inputs, combined with highly selective filters. The increased selectivity is made possible thanks to a new filter technology, developed by Unitron. The Super Profilers have 2 super-selective filters, with an impressive rejection of 30 dB at only 1 MHz! They also have a frequency conversion function, enabling the user to shift a multiplex to another frequency, so he can really manage his own frequency plan!"

These new products are to be unveiled at the ANGA Cable show in Cologne next month. They promise to send details then.

http://www.johansson.be/en/welcome.html
Very interesting, to me if to no one else.

I presently have to pre-filter off some strong, alternate channels because the model PFA-6600 filters aren't sharp enough or deep enough for some of my local situations.

If the new version can take adjacent channels 33-36 and blockshift them down to 10-13, that would help me a lot. For that matter, if it could shift two such blocks, such that I could put three adjacent channels on 2-4 and two more on 5 and 6, it would help me even more. When operators in my market have tried to individually heterodyne shift them to adjacent VHF channels, they often enounter adjacent channel interference.

There just isn't going to be much demand for this product. I might buy a bunch just so I'll have them when they are no longer available. Back in 2008, North American cable closed out on its last 23 PFA-6600s for $100 each, and then, all nof a sudden, demand came back for them and I think the typical sales price is now around $700 each.
AntAltMike is offline  
post #251 of 251 Old 04-28-2011, 02:59 PM
Member
 
fredd's Avatar
 
Join Date: Dec 2003
Location: New Jersey
Posts: 83
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Just to follow up on an earlier post, I finally got back to the MATV system in the senior housing building in Summit NJ. After re-orienting the antennas I located the head end cabinet in a utility room behind the elevators. The old system had a single down lead into a couple of hi/lo+UHF splitters, a VHF channel separator, and a bunch of single channel strip amps (2,4,5,6,7,9,11,13, B-T SCAs) diplexed in series. Since 7,11, & 13 are still VHF from NYC I tried re-using three of these but could never balance all three together so I finally gave up, pulled the lot of them (except ch-6 which handled the cctv lobby feed), and just installed a PGA-52 launch amp fed directly from the antenna down lead splitter. The amp is feeding one splitter that in-turn feeds several multi-tap directional couplers which feed the RG-59 coax distribution net. With a bit of tweaking at least 12 main channels plus subs, everything but channel 11, was coming thru on the top floor, so maybe a success. Does anyone know how reliable these Tradewind amps are? The one I installed seemed to be running a bit hot. (BTW, the Tradewind PGA-52 that Pace sells looks almost identical to, and is spec'd the same, as the Tru-Spec TA-52 for ~$100.00 less -are they the same amp?).
fredd is offline  
Reply HDTV Technical

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off