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shall
04-02-2003, 01:02 PM
Just purchased a VT2 system with BOB. Have noticed that svideo source from a DV camera or deck looks good but when I connect a composite color bar signal from our Tectronix TSG 170A sync generator the video is very noisy (lots of chroma noise). We have tried different cables, different inputs on the BOB, tweaking the proc amp, and anything else we can think of. We have been able to minimize it using the proc amp but not eliminate it. Anyone have an idea why the video would be so noisy or is it possible we have a deffective Toaster?

jcupp
04-02-2003, 03:12 PM
Do you see weird rotation on the Vectorscope?

I have a customer who has had this issue, if you have the rotating thing I'd say it's a bad Toaster.

shall
04-02-2003, 05:36 PM
Hi Jeff,
I don't see anything unusual on the vector scope but I just discovered another problem. When doing a corner wipe to simulate a PIP the wipe is very distorted and and the video in the wipe is unstable. I have reseated all cards and VT to BOB cables but no improvement. Any other ideas?

jcupp
04-02-2003, 06:32 PM
That's pretty strange. Does it do this when wiping between, say, two still graphics from the CG or Aura? If not it's probably related to your first problem. If you see the problem with images not coming in to the Toaster analog you might have some weird software problem. But either way this is a new one on me.

SBowie
04-02-2003, 07:04 PM
Originally posted by shall

I have reseated all cards and VT to BOB cables but no improvement. Any other ideas? When diagnosing stubborn problems I generally try to get a minimalist solution working correctly and then expand until I hit the 'trouble spot.' Have you tried bypassing the SX-8 temporarily, just going directly into the Toaster Input?

shall
04-03-2003, 09:18 AM
Yes, I bypassed the BOB and using the octopus cables I still see the problem. When everything is hooked up normally it shows up on the toaster vision monitors and the the master monitor as well. I haven't tried a wipe using the CG as a source yet.

Jim Capillo
04-03-2003, 11:23 AM
Have you connected the bar generator to an external waveform monitor to see if it conforms to legal video ? You might have an overdriven signal at work there......

SBowie
04-03-2003, 12:00 PM
Originally posted by shall
Yes, I bypassed the BOB and using the octopus cables I still see the problem. When everything is hooked up normally it shows up on the toaster vision monitors and the the master monitor as well. I haven't tried a wipe using the CG as a source yet. Have you found the Advanced Settings panel yet?

If not, open a Proc Amp, and right click on it. Select Avanced Settings. there's a LOT of stuff in here. I would start by seeing if setting "Luma Filter" to "enabled" made a difference.

shall
04-03-2003, 12:28 PM
I've checked the color bars signal on another scope and it is perfect. I have been into the advanced settings in the proc amp and none of them seem to help. I can reduce some of the noise on bars by reducing chroma and tweaking U and V offsets but then the video isn't standard NTSC. Could this be a software problem or is it more likely a hardware issue?

SBowie
04-03-2003, 01:16 PM
You've doubtless already tried changing the input termination?

EanJay
04-04-2003, 06:30 AM
just wondering if there are 'ground-loops' in the system?

EanJay