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Simple video contrast attenuator

Discussion in 'Home Cinema Building DIY' started by Darren Blake, May 12, 2004.

  1. Darren Blake

    Darren Blake
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    Hi all,

    My wireless video sender may be outputting a way-too contrast-y image, which is causing crosstalk onto the audio channels when high-contrast stationary images are displayed (like the Sky programme guide).

    To test this I would like to be able to add something to the composite video line out of the sender to knock down the contrast and/or brightness a touch.

    Is there a simple circuit that I can build that will do this just to test the theory?

    TIA.
     
  2. Darren Blake

    Darren Blake
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    No one? :(

    I'm only after something simple. Would a potential divider work? Any ideas on what value to use for the variable resistor so as not to mess up the 75 ohms impedance matching on the video line?
     
  3. Big Al

    Big Al
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    What make is your video sender?

    Some have a switch which allows differnt contrast settings

    Big Al
     
  4. Darren Blake

    Darren Blake
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    Hi Al.

    Its a Digisender X2 (DG200) and yes, it has the contrast switch. I'm on the lower setting and it is still too much.
     

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