VQS-01 help

[blamelewis]

Hi all,

I'm setting up a show using two separate Cat systems, each with the following setup:

Output 1: Monitor at 1024x768, 75Hz refresh rate
Output 2: VQS-01 to four projectors, VQS is set at 2048x1536 @ 38Hz refresh rate.

I'd tested it with one machine feeding four wee projectors - all was working - then switched to both machines feeding 8 LCD monitors - at this point four of the screens started to show a nasty interference pattern, and the endless fault finding began. After lots of swapping out cables, switching VQS boxes (the interference stayed with the one particular VQS box) and many reboots and mode switches on the VQS I returned to the original test setup to find the interference was now on the wee projectors too! Argh!

So my question is... wtf?

Or more usefully, does anyone with experience of VQS boxes recognise anything here - my concern is that a fault has developed in the VQS as it initially ran fine to the wee projectors.

Any ideas, advice, pension recommendations welcome.

Best

Tim

[Mr_P]

they can be a real pain....
do you have a photo of the interference?
It is possible that a fault has developed with the VQS box - I've seen this before too...

Might be worth trying some decent VGA DA's with buffering and isolation (Kramer VP-3xL) - these work with similar issues on Matrox TH2G (if your issues is the same)

If you can survice without LCD on output 1 - try a Matrox TH2G and use output 1 for a projector too - or 2 x Matrox DH2G. (Would also suggest the use of the VP-3xL Da's too)


Simon

[blamelewis]

Hi Simon,

you're helpful as always

I arrived at a workaround similar to your suggestion: The second machine is now hooked up to a triple head and the fourth projector will be fed by its "monitor" output - this will work as the show will be controlled from the other machine so we won't need to see the Cat interface on machine B except for setup...

Interesting to hear that you've heard of VQS boxes developing faults - it did seem to worsen, and I didn't take photos but the interference started as intermittent black lines across parts of the monitors (we wondered if it was dirty mains...), then as we troubleshot it seemed to develop into more colourful bursts of noise - mostly linear, and coupled with increasing dropouts, the VQS losing signal completely for a time (the Green "Ready" LED by the power LED would flicker or go out as this happened.)

I ran out of troubleshooting time, but hope to get back to it. One suspect is the DVI cable between the Mac Pro and the VQS, and I did swap it for a new one but the Mac failed to recognise the VQS with the new cable, (it found a "VGA display" rather than a VQS-01 so I switched back.)

Are there issues with length of DVI cable - or different types? The new one was 3m and the old one about 1.5.

Stumped, tired and out of time.. but at least I found a workaround... Thanks for suggestions!

Tim

[Mr_P]

unplug everything and reset PRAM sometimes worked...
cant really offer any more suggestions - apart from send it back to Datapath. Shortest DVI-D cable is best at that resolution.

Glad you had an alternative solution. Matrox aren't 'perfect' - but better value for money....

Simon