hdtv

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mcelweec@gmail.com

CMAC1
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Electrician
i have to provide cabling for 9 hdtvs located 200ft from their cable boxes,could someone recommend which would the most cost effective cabling be without losing quality,btw this a commercial building with fluorescent lighting.
 
mcelweec@gmail.com said:
i have to provide cabling for 9 hdtvs located 200ft from their cable boxes,could someone recommend which would the most cost effective cabling be without losing quality,btw this a commercial building with fluorescent lighting.
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Maybe cat 5 cable with HDTV Baluns on each end. I have never used them myself but sounds like a great idea. I have been thinking of using them for some security camera's.
 
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great idea but it says they're only good to 150ft ,i've got suggestions of using shielded component cable or 5 individual cat 5 runs,i'm just wondering is there another option,or what the pros and cons are.
 
Use cat 6 instead of cat 5 if you go this rout. The conductors are a bit bigger and can carry a better signal longer distances. I have used this in the past and soldered VGA ends on the cat 6 to send security monitors 200+ feet. There was some ghosting though. Your best bet If you really need HD would be to send 3 RG 6 coax and terminate RCA jacks on them for component video and 2 16-2 stranded for audio.
 
As previously stated in several of the posts, Cat5e or Cat6 are great solutions! The Baluns come in both passive and powered baluns. The powered baluns work well for longer distances. They also have powered baluns that will pass an HDMI Signal!

As far as other solutions that will work well...

Multi-conductor cable-
Multi-conductor cable (aka Mini59) is a cable that contains anywhere between 3 and 7 mini RG59 cables. You can terminate this cable with RCA, BNC, or VGA. I have successfully run and used this type of cable up to about 300'. Downside the terminations take several minutes to terminate each end. When you are dealing with component video and audio (5 wires on each end) it could take as long as 30 minutes per cable to terminate this wire.

Rapid Run -
A rapid run cable is a pre-terminate cable that comes in multiple lengths (25', 75', 100', 125', etc.). This cable is manufactured by cables to go. The cable comes with a proprietary connector on the end that allows for a wide variety of selections for connections (VGA, Component Video, Composite Video, S-Video, HDMI, etc...). This cable allows for quick termination saving time! The downside is you are paying a little more for this product due to the time savings.
 
Like anyone will really cares, using the term "balun" for a device that allows CAT 5 cable to be used for something to me is like scratching fingernails on a blackboard. This is getting to be like the RJ-45 thing and needs to be killed before it takes root. Notice Geffin in that link above properly calls them extenders. Another accurate term is converter. Just don't call them baluns!

-Hal
 
Is balun necessarily inaccurate? You take the information from an unbalanced medium and put it on a balanced medium, and then do the opposite at the other end. The exact same principle as 300-75 ohm transformers for TV or 10k to 600 ohm transformers for audio systems.
 
No. CAT 5 isn't used necessarily because it can be balanced. I just makes for a transmission medium much like when used for ethernet. In the simplest of uses where twisted pair is used for audio or baseband video it would be accurate to call the passive devices (simple transformers that have been used for ages) at each end that convert unbalanced inputs and outputs "baluns". That's where the term was coined. But unfortunately technology has become dumbed down in recent years since manufacturers became greedy and want to market to everyone, not just to those that have the technical experience and education like years ago. So "balun" is the catch-all name that wanna-be techies are capable of understanding. It's kind of like a little kid saying he has a boo boo but a doctor would have a different name for it.

-Hal
 
luckylerado said:
Your best bet If you really need HD would be to send 3 RG 6 coax and terminate RCA jacks on them for component video . . .
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I prefer an all-copper RG59 for audio and video over RG6, which is usually a copper-clad conductor in an aluminum shield. The RG6 is too thick and stiff, and harder to terminate in RCA's or BNC's.

I ran five RG59's for my CRT projector, terminated with BNC connectors, which carry RGB-HV from a VGA breakout cable.
 
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Larry, RG-59 won't work well (if at all) in lengths over say 75 feet or so. For HD I wouldn't trust RG-59 over 50 feet max.

RG-6 is the only safe way fro runs over 50+ feet in HD , and there is one critical thing: The cables MUST be the exact same length (any RGB group to a specific monitor that is) with a tolerance of 1/2 inch or less. Seriously (and I can think of a few who will come along and challenge this) the signal is of such a high frequency and the time-alignment of each signal in relation to the other is super critical. Any error in cable length will result in color smearing, ghosting or sync issues.

The Gefen CAT 5 links posted earlier are the best bet and they work quite well. But be sure to get the long-range versions!!
 
Just a heads up - for analogue video use, Cat6 is much worse than Cat5 due to Cat6's superior quality, strangely enough. When using twisted pair extenders, the three RGB or compjonent video signals are sent over a pair each, and the problem with Cat6 is that due to its construction the electrical lengths of the four pairs are quite different from each other, and enough tocause color smearing on the display.

So if you are using an analogue extender with Cat6, make sure the extender has 'trim' controls on it.

Heres a picture from a local supermarket in-store monitor with this problem; note the extra colors on the inside of the white box. This is a camera phone pic so not very good, I'm afraid...

cat6_video_smearing.jpg
 
Cat6 is much worse than Cat5 due to Cat6's superior quality

Well, I wouldn't say superior quality. I would say better ethernet performance which is what it's designed for. Use it for something it wasn't designed for and all bets are off and this is a good example. It's pretty well known that you don't want to use CAT6 with twisted pair extenders.

-Hal
 
hbiss said:

It's pretty well known that you don't want to use CAT6 with twisted pair extenders.

-Hal
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This company seems to sell "extenders" that use CAT6.
http://www.gefen.com/kvm/dproduct.jsp?prod_id=8081

I am not challenging your statement I am just wondering why they would say that it provides a "perfect image". I know it is sales pitch but if it is widely accepted that CAT6 is not suitable for this application who would buy that equipment for $600.00?
 
I am just wondering why they would say that it provides a "perfect image".

Because that one is designed for CAT6 and says so. If one doesn't specifically say it is for use with CAT6 don't assume that you can use it.

-Hal
 
mxslick said:
Larry, RG-59 won't work well (if at all) in lengths over say 75 feet or so. For HD I wouldn't trust RG-59 over 50 feet max.

RG-6 is the only safe way fro runs over 50+ feet in HD , and there is one critical thing: The cables MUST be the exact same length (any RGB group to a specific monitor that is) with a tolerance of 1/2 inch or less. Seriously (and I can think of a few who will come along and challenge this) the signal is of such a high frequency and the time-alignment of each signal in relation to the other is super critical. Any error in cable length will result in color smearing, ghosting or sync issues.

The Gefen CAT 5 links posted earlier are the best bet and they work quite well. But be sure to get the long-range versions!!
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RG59 will "work" for hundreds of feet with analog HDTV. The longer it gets, the more HF rolloff you have which translates to a softer image. I do agree though in that I would use COPPER RG6 such as Belden 1694 over 50 feet. CATV RG6 is often copper plated steel as noted in the above post. That's fine for RF but not so good for baseband video.

1/2 inch is a good bench mark. Too late tonight to do the math but on a consumer HDTV signal there isn't much energy above 20mhz and that's only in the luminance channel. An inch or two would be OK on a 50foot plus legnth. In reality old NTSC video was actually more sensitive to timed cable lengths in broadcast applications. That's because the chroma was amplitude/phase encoded and every 6 inches meant a 1 degree hue shift.
 
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