HDMI over cat5 problems

[dedwards96]

Hi,

 

We have a Sanyo XM150 projector mounted on a lighting rig bar at our school. Having moved the projector to a new location, the image displayed by the projector is black with thin yellow lines at small regular intervals right across the image.

 

What is the likely problem with the setup?

 

Computer HDMI output --> HDMI/Cat5e sender (2m HDMI cable) --> HDMI/Cat5e reciever (2x 15m cat5e cable) --> Projector (2m HDMI cable).

 

Any help will be greatly appreciated as we have a show on Friday and at the moment we don't have a working projector!!

 

Thanks, Dan.

[jonathanhill]

I try and stay away from video, but from what you have posted, my first visit would be to the Cat5 cables, as they are likey to be the weak link. Do you have a test tool for Cat5, as it will make the fault finding easier? Failing that do you have some known working Cat5 that you can lash in for testing purposes? I would also look at the powering arrangement for the transmitter/receiver.

[bruce]

Did it work before you moved it?

 

Are you using the same CAT5 cables?

Are they definitely plugged up the right way round?

 

Is it powered at both ends or just one? If just one, are the remote end LEDs lit?

[dedwards96]

We have two permanently installed pairs of cat5 cables which enable us to place the projector in either of two positions, both pairs of cable run to the same position in the corner of the room.

The projector was working perfectly using one pair of cat5 cables before we moved it, however we have successfully used both sets of cat5 cables recently.

I suppose the likely problem is the cat5 cables but I will check every other possibility first because that is the most difficult and time consuming component to replace!!

Thanks for your suggestions

Dan :)

[timsabre]

Couldn't you just run a temporary cat5 across the floor to test?

[TonyMitchell]

I'd look to test the projector first, either with a direct VGA or HDMI source?

 

I'd also release and re-install the lens, in case something's adrift since you moved the projector.

 

 

[Pete McCrea]

HDMI over CAT5 is a fiddle, and not really that reliable.

 

Which make and model of CAT5 boxes are they?

 

Speaking to Extron recently, there have been shifts in the chipsets used to make the CAT5 solutions work, with many manufacturers going to Valens HDBaseT chipsets. These can be quite picky about the cable, and the quality of termination on the CAT lines. It might be that the lines used previously were in spec, but the new lines are now out of spec, so giving the issue.

 

Also worth testing the projector directly with the source, just to eliminate the CAT5 system.

[Nick Mawer]

HDBaseT is an interesting subject. First thing to say is that properly designed HDBaseT products are actually less picky about cable type than many of the older technologies. However, HDBaseT org claim that you can go 100m over unshielded CAT 5 from point to point, but if you are operating in a noisy environment, or if you are bundling cables, then that range is effectively considerably reduced. In our experience many of the issues that faced earlier adopters of HDBaseT products were solved if the installer was able to swap to shielded CAT 6. Furthermore, the Kramer BC-DGKat623 cable that we developed to complement our old non HDBaseT products is very effective with Kramer HDBaseT machines as well, allowing an image to be sent 130m rather than the claimed 100m of the chipset manufacturer.

HDBaseT Lite products are artificially limited to 70m by the chipset, so extra distance is not achievable with these. None of this however will help the OP I don't think.