Digital projector

[Mikebits]

Today was the first day of my schools new semester. In my botany class the professor was having difficulty with his overhead presentation.

Not that I am obsequious, but thought I might be able to help jumped up and started to dongle on cables and such not much help either

Here is the setup and symptoms:

A laptop PC video along with USB is wired into a desktop PC. From there, the desktop is wired into the overhead projector. It looked like there was a USB connection, and also a VGA dsub and a video RCA cable.

The symptom was that the video would blink in and out, for a glimpse moment you could see the presentation on the screen, then it would blink out and a message No RGB video. I suspected a bad cable, but could not figure out the video source as there were multiple connections (Standard video and DB9). Anyone know anything in this area?

 

[killivolt]

Video settings in the Laptop reduce or increase.

Today was the first day of my schools new semester. In my botany class the professor was having difficulty with his overhead presentation.

Not that I am obsequious, but thought I might be able to help jumped up and started to dongle on cables and such not much help either

Here is the setup and symptoms:

A laptop PC video along with USB is wired into a desktop PC. From there, the desktop is wired into the overhead projector. It looked like there was a USB connection, and also a VGA dsub and a video RCA cable.

The symptom was that the video would blink in and out, for a glimpse moment you could see the presentation on the screen, then it would blink out and a message No RGB video. I suspected a bad cable, but could not figure out the video source as there were multiple connections (Standard video and DB9). Anyone know anything in this area?

I'm not really sure what the dB9 was being used for maybe they are trying to control the projectors inputs switching it from a program in the desktop via rs232.

The problem sounds like the VGA setting from the laptop maybe to high resolution.

kv ?

Usually I just deal with a straight VGA out of a Laptop into an a+b switch and then into the projector.

 

[Mikebits]

I'm not really sure what the dB9 was being used for maybe they are trying to control the projectors inputs switching it from a program in the desktop via rs232.

Oops, I meant VGA connector not DB9.

 

[JimB]

Of the video projectors with which I am familiar, none of them give a sensible display if the video from the PC/laptop is more than 1024x768 pixels.
Right click on the desktop area to display the Display Properties, and adjust the screen resolution in the Settings tab.

The USB is usually a "mouse" connection, so that the remote controller for the projector can be used to page forward and back through the presentation.

I dont undersatand when you say that the video from the laptop was connected to the PC, are you sure that it was not to a switch box of some kind to select PC or laptop?

JimB

 

[HiTech]

The symptom was that the video would blink in and out, for a glimpse moment you could see the presentation on the screen, then it would blink out and a message No RGB video.

That is classic response for a projector when a resolution setting from the 'puter is higher than the proj's specs. However what concerns me is that you said "for a glimpse moment you could see the presentation on the screen" ... by that, are you saying that you could see the PC boot up in DOS mode and then when Windows began, the image disappeared? Or could you see the desktop image for a glimpse before it disappeared? If the former, that definitely indicates resolution settings need to be lowered on the PC. If the latter, I would suspect a sync issue within the projector.