Video output problems

[georgew]

I'm seeing strange problems with the video coming out of the VT being incompatable with other devices.

Connecting it to a large screen TV, it worked finr for 20 minutes, then the TV decided there was no video there. A projection TV was displaying alternating bands of bright and dim video, but it was not bad. This is using a composit out.

On our DVD recorders, the Sony dvd recorders work great, but the gateway AR-230 recorders see the color turning on and off quickly using either the composit OR the s-video outputs. The VT is configured to output in s-video mode.

One model of cheap LCD monitor sees a combination of horizontal banding and 3-5hz color-nocolor flicker. Two other LCD's work normally.

The problems are independent of the port in use. In all cases, I get normal behavior if I install a device that "likes" the video signal. I'm seeing around 50% compatability. Short cables... We are on the same power...

The devices that don't like the vt output work fine directly monitoring camera output, so it is not a huge problem, except we can't feed our video to the house monitors.

[mbloor]

It sounds to me like VT`s master oscillator is off frequency.
Do you have genlock ? If so try genlocking to one of the input sources eg a camera, that you said your monitors were happy with, if it gets better, then VT`s free run frequency is off. You can check this fairly easily IF you have standalone Vector and Waveform monitors, basically feed a good known reference into the external sync inputs of the WFM and Vectorscope, eg a sync pulse generator, off air etc, now display VT`s output referenced to the external sync you applied, if its running through very quickly, or the vectors are rotating more than about 10 revolutions per minute, its off spec.
Mark

[georgew]

I will try that out... I don't have a vectorscope, but I might be able to lay my hands on one...

Is there an alignment procedure, beyond genlocking to a good signal?
Or is this a warranty issue (brand new vt4)?


Thanks!
George

[mbloor]

Basically if its the VT4 card, just connecting a "good signal" hopefully will pull the output good. If it does, then disconnecting it results in the output going off, then I think a phone call to tech support may be in order.
Mark