AVS Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
718 Posts
Discussion Starter · #1 ·

·
Registered
Joined
·
2,818 Posts
Very cool, except for the external power requirement.
Quote:
But there’s always a trade-off, though thankfully this time it’s a minor one. Unlike standard copper HDMI cables which you can just plug in and have work, fiber optic-based HDMI cables require a power source, which in this case is pulled from a USB port. You’ll find that most modern hi-def TVs have at least one USB port on the back, but if not you can always add an AC to USB adapter to your TV’s power strip.
Any rough guesses on pricing?
 

·
Registered
Joined
·
4,649 Posts
This product has already come up in another thread, but it might as well have its own thread.


There are two issues with power. As already mentioned, the sink end requires a USB port for power. The other issue is that the source source end requires power from the source's 5V pin on the HDMI connector and the cable is speced at .6W at the source end. That is 120 mA, more than the 55 mA the HDMI spec requires a source to provide. With all the problems people have had with switches, splitters, etc. that are powered this way, this doesn't seem like a good way to go. Of course, one can always stick a USB power injector in the chain at one end, and a HDMI power injector in the chain at the other if you don't mind the kludgey look. IMHO this part of the product was not well thought out. One would think that they would have anticipated the requirement and included a socket to plug a DC power source into on each end.


Still, it is an interesting product. Unfortunately, it is not available yet. I'll be looking forward to seeing some lab test results on it and the ATC certification, and some prices.


It might have been better if the product incorporated a short whip of HDMI cable at the sink end, or both ends, instead of integrating everything into the plug. I think you are going to have to use a port saver with in most cases considering how long the plug is. I cannot image it plugged directly into a wall mounted display.
 

·
Registered
Joined
·
1,291 Posts
I like this, but isn't it essentially a balun with a fiber optic cable?


We all know of the various problems with other baluns, will this be "problem free"?
 

·
Banned
Joined
·
3,692 Posts

Quote:
Originally Posted by sebberry /forum/post/21023907


How is it different?

Borrowing from Wiki-you-know-what...


"A balun ( /ˈbælʌn/) is a type of electrical transformer that can convert electrical signals that are balanced about ground (differential) to signals that are unbalanced (single-ended), and the reverse. They are also often used to connect lines of differing impedance. The origin of the word balun is bal(ance) + un(balance)."


In this case you are transforming from electrical to optical. There is nothing balanced or unbalanced on the optical side, although we could discuss the polarity of the signal instead.
 

·
Registered
Joined
·
4,649 Posts
How is it the same, other than overall functionality? The technology is completely different. It is like saying how are snail mail and e-mail different. Fiber solutions are not subject to most of the limiting factors of a copper solution. They may have their own problems, though.


FWIW balun isn't even a good term for HDMI Cat 5/5e/6 media adapters. The TMDS lines over which video and audio are transmitted are balanced from end to end. And the other, unbalanced, lines aren't necessarily converted to balanced lines.
 

·
Registered
Joined
·
1,291 Posts
My apologies, I was using the more generic definition for "balun" and not the technical one.


For example, looking at an HDMI over Cat6 "balun", ie, Monoprice. There's some electronic wizardry going on in there and sometimes it screws up things like handshaking, HDCP, etc...


How are the electronics different in this optical HDMI cable such that they will avoid issues with HDCP, etc..?
 

·
Registered
Joined
·
4,649 Posts
There is very little electronic wizardry going on in the typical two cable Cat 5/5e/6 media adapter. The closest to wizardry you will find in most is an equalization circuit equivalent to what you can buy for a HDMI cable and is often found in splitters and switches. The typical media adapter cannot even do as well as a good HDMI cable with an equalizer. HDMI cable is a superior medium for the purpose to Cat 5/5e/6. You would have to use Cat 7/Class F, and properly ground it, to equal HDMI cable. Most of the problems you see with media adapters stem from the limitations of the cable used that result in high frequency attenuation, cross talk between lines, intra-pair and inter-pair skew, and external noise. Fiber doesn't have these problems.


There is electronic wizardry going on in high end Cat 5/5e/6 media adapters that use a single cable, in particular those that use the Valens chipset on which HDBaseT is based. But that is a whole other kind of device.
 

·
Registered
Joined
·
1,291 Posts
Thanks for that!


I really wish fiber would replace HDMI. Imagine how much easier it would be to rig up a system with toslink style cables than HDMI cables.
 
1 - 13 of 13 Posts
Top