Knox Studio 40.ND Character Generator Trouble

[Chip Chester]

I wonder if it might have an internal/external choice in some menu. Since it puts out a image with nothing else attached, we know it has some internal reference capability. It may not auto-switch to correctly handle external sources... or it may be set for PAL or something like that, too...

Of course, it could be busted, as you thought, too...

Chip

[uxwbill]

Originally Posted by NJRoadfan

I just find it weird that the chroma shift doesn't evenly fill the entire frame during the first part of the sample clip.

I find that extremely odd as well. Even in a view where the camera doesn't move, the picture color is not always stable. Since replacing the cap, it has "snapped" to the correct colors for just a moment or two.

Originally Posted by NJRoadfan

EDIT: I got a shot of the rear, no reference input. Its too bad you don't have a vectorscope handy, that would aid in diagnosing and adjusting color.

I did get your message about the vectorscope plug-in for VirtualDub. I just haven't tried to use it. I don't know how much it can help as I already know there's a serious problem. I just don't know why, or more importantly, what should be done about it. (That and my copy of VirtualDub seems to be uncooperative at the moment in that it will crash-by-sudden-disappearance.)

I do plan to try the S-Video input as soon as I figure out where those cables are.

Originally Posted by Chip Chester

I wonder if it might have an internal/external choice in some menu. Since it puts out a image with nothing else attached, we know it has some internal reference capability.

As best I can tell, the unit's program (which seems to be quite rudimentary) only handles character generation...though I definitely don't have and could not get any documentation. What I know about it is simply "reverse engineered" from pictures of the Knox keyboard and experimentation. I have not found any evidence of an onboard menu.

Originally Posted by Chip Chester

It may not auto-switch to correctly handle external sources... or it may be set for PAL or something like that, too...

When I first got the unit, I noticed that the information label on the bottom said "Studio 40.ND PAL". This made me pretty sure it began life as a PAL unit. Yet I know the unit was used here in the US and why the previous owner would be using PAL equipment instead of NTSC is beyond me.

I really did think this might be the reason for the lack of picture related color, but it doesn't explain the shift in this unit's behavior. Since I haven't ever tried it, I'm also not sure what would happen if one were to display a PAL signal on an NTSC TV. I have not tried feeding the unit a PAL signal to see what would happen.

I couldn't imagine that Knox Video would have designed the unit such that it had different circuit boards for each television standard. After poking around, it seems the video board can be switched between PAL and NTSC by way of a jumper. A Hitachi HD440072 is used for sync signal generation. It is to be a multi system capable part (for PAL, NTSC and SECAM).

There's also no explanation for why the unit clearly seems to be putting out an NTSC color signal...the best I can say is that I don't think it's set up for PAL operation any longer.

I was really hoping someone might have some documentation hiding in a forgotten file somewhere.

[Chip Chester]

Found a couple of links you may have run across:

http://www.videomaker.com/article/17...&gbv=1&ct=clnk

http://www.shopping-advices.com/feat...generator.html

Do you have the "instructional overlay" outlining basic operation? If not, perhaps one of the auction sellers could make you a copy before sending it away. The video technologies article says the manual is only 5 1/2 pages long...

Also, there are two adjustment pots (with hex nuts) tucked up high on the back panel... you may have a go at those... after marking their current position fairly accurately. Best to do once you get video scope going.

And with regard to PAL... they (or you) may have modified the unit's main video board output for NTSC, but the video input you're using might still be PAL... which would probably look squirrely. The fact that it snaps into correctness on occasion leads me to believe it's a sync problem.

Chip