Dummy-Connector

 

For whom is the dummy connector interesting?

Mostly it´s interesting for laptop owners with a nVidia GF2Go-chip and a TV output. So far the support of TVTool for this chip is relativly limited, that means you have to go the complicated way through the nVidia driver settings to turn on the TV output. Only then TVTool can be started. But this doesn´t apply if there´s a monitor attached to the laptop. In this case the whole functionality of the tool can be used. But I guess you don´t want to carry a monitor always with you just to turn on the TV mode comfortably. At this point the monitor dummy comes into play.

 
The Monitor-Dummy

 

But also for users who want to attach their PC to the TV exclusively without connecting a monitor this dummy can be a help. This is done more and more, the PC is used as a movie- or MP3 server and is connected to the hifi-system in the living room. Some graphics cards makes trouble though, if no monitor is found at the VGA connector. This can lead to different problems. In some cases you cant change the graphics mode anymore, or you can´t playback any DVDs. This is true for all BT868 based cards for example. In this case the monitor dummy solves the problem, as it cheats the graphics card and let it think there was a monitor attached.

 

How is the connector made?

That´s really easy and costs less than 3 bucks. All you need is a VGA connector, its housing and three 75 Ohms resistors. You should get these parts in every electronic store. Now the resistors are soldered to the connector in this way:

 

 
VGA connector: pinout seen from the soldering site

 

The pins used have this meaning by the way:

  • 1 Red Video
  • 2 Green Video
  • 3 Blue Video
  • 6 Red Ground
  • 7 Green Ground
  • 8 Blue Ground
It could look like this

 

That´s all to let the card think there was a monitor attached. Now TVTool can be used with its full functionatliy also on laptops and PCs which are connected to a TV only. For PCs you should place TVTool in the startup folder with the command line option /tv, so the TV mode is started together with Windows. The booting phase can not be seen on the TV in this case of course.

    • Note for laptops: After attaching the dummy you have to turn on the simultaneous output to the internal TFT display and the monitor firstly. This is usually done with a hotkey on the keyboard. Maybe you see colored patterns during TV mode on the TFT display, this happens because TVTool doesn´t turn off this device during TV mode yet.

     

That´s it. Of course it´s planned to further develop the tool so that such a dummy is not necessary anymore especially for laptops. But until this is done I guess it could be a nice solution for some users. The reproduction and the usage of this connector is at one´s own risk of course!

(c) JB 2001