Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums > Pro AV FUD Forum Archive
Cat 5 Balun issues
drewgandy:
I've recently installed Niles C5 passive baluns in 2 different jobs and have had ghosting issues in both. The first one is the HDDA model which is for component video. The run is on the order of 25 feet on Category 6 cable. Severe ghosting (duplicate image shifted slightly to the right) that is significantly better when I bypass the DA amp just ahead of it but the ghost is still there. The other job is a 110 foot run to a projector with the VGA model. In this case I initially tested the Cat6 run with a battery powered laptop. Macbook Pro -> displayport/VGA adaptor ->short VGA cable -> balun ->Cat 6 cable -> short VGA cable to the projector. Suspecting the laptop (macbook pro 13) may need a little "help" I added a VGA distribution amp ahead of the balun but still the same ghosting. Anybody have trouble with passive baluns in this way?
drew
Mac Kerr:
drewgandy wrote on Wed, 22 December 2010 22:34
I've recently installed Niles C5 passive baluns in 2 different jobs and have had ghosting issues in both. The first one is the HDDA model which is for component video.
Are you using low skew category cable?
Mac
drewgandy:
Mac Kerr wrote on Wed, 22 December 2010 22:03
drewgandy wrote on Wed, 22 December 2010 22:34
I've recently installed Niles C5 passive baluns in 2 different jobs and have had ghosting issues in both. The first one is the HDDA model which is for component video.
Are you using low skew category cable?
Mac
I've not noticed mention of skew (or low skew) on any of the baluns I've dealt with so far. If it meets the Cat 5/6 spec it should meet the Cat 5/6 spec (including skew), right?
The Cat 6 is this http://www.parts-express.com/pe/showdetl.cfm?Partnumber=101- 037. The component baluns were also tested with a coil of cat 5 that I happened to have but the ghosting seemed to be exactly the same.
drew
Update:
I see that skew is not typically a troublesome issue with data but can be with video. If I understand it correctly, skew is a very short amount of delay between conductor pairs that mucks with sync or what might be called convergence? What I'm seeing with the component seems like reflections of the same image on all three colors, not a mis sync of the colors. The VGA issue I'm not so sure about. But both runs are relatively short and skew seems to be an issue at the longer end of things. ?
Mac Kerr:
drewgandy wrote on Wed, 22 December 2010 23:28
Mac Kerr wrote on Wed, 22 December 2010 22:03
drewgandy wrote on Wed, 22 December 2010 22:34
I've recently installed Niles C5 passive baluns in 2 different jobs and have had ghosting issues in both. The first one is the HDDA model which is for component video.
Are you using low skew category cable?
Mac
I've not noticed mention of skew (or low skew) on any of the baluns I've dealt with so far. If it meets the Cat 5/6 spec it should meet the Cat 5/6 spec (including skew), right?
The Cat 6 is this http://www.parts-express.com/pe/showdetl.cfm?Partnumber=101- 037. The component baluns were also tested with a coil of cat 5 that I happened to have but the ghosting seemed to be exactly the same.
drew
You should be using low skew cable with component video over passive baluns.
Mac
chris fletchall:
I have just had the same issue with intellix baluns in a whole house distribution. The ghosting was horrible. On a Direct TV guide it was as whole letter off.
We spent two weeks on the phone with support from Niles, Intellix and Vanco before some one said try an active balun.
The fix that we found was Elan's HD baluns
http://www.elanhomesystems.com/productdetail.asp?id=95
They have a gain and footage control that cleaned up the ghosting. Cost a little bit more and they need power but a happy customer and a good picture was worth it to us.
Navigation
[0] Message Index
[#] Next page
Go to full version