Pros & Cons of HDMI Baluns

There has to be more to this article, right?  There are so many problems with CAT5/HDMI baluns and you only list a few… with no details, no explanations, no science, no math, no history, no alternatives, no suggestions, no answers.  Is there more to your article that CE Pro decided not to publish?

WOW .... I agree that was far to simple a read. Dealing with these things on a dialy basis. I agree this was lacking as an article.Maybe this is just a quick tease to something informative coming down the pipe.

This unfortunately IS the full article, as also published in the last CEPro issue. I am very disappointed as well in what was written.

Unfortunately, we don’t give Jeff enough space in the magazine. We’ll ask him to do something a little more substantial on the subject for online. Whaddya say, Jeff?

Thanks for the feedback, readers.

Julie,
Nothing personal, but we’re talking about one of the biggest issues/problems in our industry, and you guys can’t afford to give Jeff more space?

If you’re looking for more space to give Jeff, remove all of the reviews and opinions of 3D TV and address a real problem that dealers care about.

Not to mention, how can you ask Jeff to do something a little more substantial when you already have it? You just got done admitting you’re the ones who edited him, so reprint what he gave you in full.

Knowing Jeff personally, I feel quite confident that he spent many hours to give you a sh*tload of info while you waste valuable space asking dealers opinions about 3D TV. Fortunately for me, Jeff has already given me my private education on the matter, but it’s not my place to try to accurately replicate what & how Jeff wants to translate it to people who need to know.

Even with my private education and understanding the matter, reading this article is about as incomplete as a fetus in its first trimester.

@Dave, Although we’re right we can’t really blame Julie.  She has no clue what actual dealers actually deal with.  Posting (publishing?)stories about Netflix on game consoles, 3D TVs, Marriage in the workplace… I’m sure these are real issues for somebody somewhere.  Just not sure who.

Agreed that there is much more to this story that needs to be told.

Understanding the issues helps us mitigate them.  What about thinks like cross phase noise, parity of data in different types of Cat5 (standard vs low skew vs no skew)

This isn’t an issue of Jeff’s knowledge.

It is my understanding Electronic House is aimed at the consumer, print this type of thing there, with a full story in CE Pro for those with the aptitude and attention span.

Or maybe this could become a CE Pro Whitepaper in the Pay Per View Section if you feel it goes too far for your typical reader?

Thank you for wasting my time -you got me with a great topic- hence why I stopped and read it but as usual you don’t finish .... Like so many unfinished projects I run into lately .... If anyone reads this has an opinion on the new Crestron DM system with their Balun solution over their proprietary 8G wire ? thanks Tom

@ Tom Farinola

Crestron’s 8G is not really a new concept in general.

The 10GB Ethernet (10GE) spec has been around since 2002 for commercial 10GE Networks.

It really utilizes the same principle of Shielded Twisted Pair Cable to minimize crosstalk and enhance speeds. 

10GE typically uses Cat6 or Cat7 cables, with an overall shield and individually shielded twisted 23AWG pairs (slightly heavier gauge then Crestron).  This cable has a little faster propagation and lower latency.  It also stretches the limits of the RJ45 connector, offering a different type for better performance.

Crestron’s wire is not technically proprietary, as it uses industry standard connectors and meets certain performance specifications.  You can buy Cat5E STP cable (which is what theirs is) from many manufacturers, as long as you make sure it matches the Crestron cables specs, which they publish.

Two issues are this, and these would have been great thing to talk about in this article. 

1) Skew- If you buy a cable that outperfroms the Crestron DM cable, having less inherent skew, it may actually hurt the transmission.  Analog video extenders/baluns (like component video or RGB) hate skew in general, while digital ones actually need it to function.
Crestron doesn’t publish their engineering min and max for this on their DM extenders/baluns, at least that I know.

2) Crestron warranties the installation at another level if you use their cable, meaning that their $2-3 per foot retail cable, just may help you in the end with warranty issues.  They will be inflexible in troubleshooting DM transmission issues if you are not using their wire, even if you do your due dilligence and find the generally available equivalent in the marketplace at large.

Mark,
Right on the money! However, for all of those playing our home game and may not understand the technical jargon, the bottom line is this:

If you use a cable that can outperform a systems’ tolerance in speed, (signal going from point A to point B), the end device receiving this transmission may not be able to keep up or capture all of the info needed to receive/reproduce the signal. This would produce sparkles or intermittent blackouts on the display.

The cure for this problem, (believe it or not), is to use something along the lines of a Radio Shack coupler in line which will slow down the transmission of data. Thus, put a cheap coupler between point A + B, and you more than likely will have success. You can also achieve results by lowering the output of a single device by lowering the resolution from 1080p to 1080i.

On the other hand, if you’ve used cheap cable from point A to B, and you can’t replace it, you need to purchase a HDMI amplified coupler or balun in order to give the signal a boost to reach the required dynamic headroom required.

Long runs of HDMI can be very temperamental as we all know. If all components are not playing nicely together, (A/V Receiver, Cable or Sat Box, Blu Ray Player), you either have to speed it up, or slow it down. Where in the chain it needs to take place if there is a problem, is only done in the field by trial & error.

Therefore, my recommendation is to always have a piece of crap and a high quality balun/coupler with you at all times. I for one, always start out with the end device to display in the chain. Don’t be surprised if the cable/sat box works and the Blu Ray doesn’t. If that’s the case, you’ve just found the weakest link in the chain.

I’m not sure about that.  It is the source device, and not the cable, that determines the rate of data transfer.  This rate is based on the source’s clock speed, which is negotiated during the connection setup.  I can’t see how any cable carrying HDMI could cause the data rate to overwhelm the receiving device.

So, I wouldn’t think the idea of adding a coupler to “slow down” the data really figures.

The problem with using a low skew cable for HDMI is not that the data may be transmitted too quickly for the receiving device, but rather that cross talk becomes more of an issue.

@cm: You’re absolutely correct… In my 2nd paragraph, 1st sentence, I meant to say as you did, “source device,” instead of “cable.” As you can also see in my last paragraph, I stated to, “always start out with the end device to display…,” Thus, the “end device,” is and would be the “source device.”

After changing that one word, (my bad), you’ll see the rest of my post is in total agreement with yours.

However, the rest of my post is totally accurate regarding methods of how to speed up or slow down the rate of data transmission and correct clocking issues between devices.

I’d also like to add you don’t necessarily have to perform trial & error in the field. Just set up the components with the lengths you plan to use on your test bench 1st. If it works on the bench, typically the only problem you would have in the field is if someone puts a staple, or crimps either the cat5/6 or fiber optic cable while installing/running the cable. 

Thanks for picking that up cm!

More Blah blah blah blah blah balh blah.

@Save Dtevens: Thank you for your contribution.

BTW: You’ve misspelled your 6th, “blah,” in your most informative comment. Matter of fact, I don’t think I’ve ever seen an entire post written that consists of only 4 letter words from beginning to end. Great Job!!!

So all that being said, what is the cause for my balun to drop everything and go black? The screen goes black for 3 to 5 seconds and comes back. I have switched devices. the wire is 2 cat 6’s about 60 feet. what wires do the balun use. can I jump a negative wire to one end of the cat 6 to help pull out noise if that is the case? or do I just tell the client thats what you get with HDMI over balun?