Subject: Re: Automatic Video Switch
References: <firstname.lastname@example.org> <email@example.com>
X-Newsreader: Forte Agent 1.93/32.576 English (American)
Date: Sat, 18 Jan 2003 12:52:37 -0500
NNTP-Posting-Date: Sat, 18 Jan 2003 12:52:39 EST
Organization: Bell Sympatico
On 18 Jan 2003 08:42:41 GMT, firstname.lastname@example.org (Rolavine) wrote:
>>Subject: Re: Automatic Video Switch
>>From: email@example.com (Jeff Artz)
>> I want to energize a relay when the Receiver is on "DVD" -- This
>>relay will be used to switch the projector to the RGB inputs, which
>>are wired directly to the DVD player. Since the VCR and and Sattelite
>>are using Composite Video, I need the projector to be in composite
>>video mode unless the DVD player is selected.
>> I figure I can connect the DVD's composite output to the receiver,
>>passing it through an adapter that also has the receiver's Video
>>output going through it. By comparing both video signals, if they're
>>exactly the same (DVD selected on the receiver), then I'll energize
>>the relay, which will switch the projector into RGB mode. Otherwise,
>>the relay will not be energized, and the projector will be in
>>Composite Video mode.
>> How's that sound???
>Why not just use a programable remote that has macros, like the one that came
>wth my Pioneer Receiver. Set it up so that when you push the DVD button is
>sends out IR codes to switch you projector to use the what your calling the RGB
>inputs (I'm guessing you mean component video?).
>How can you switch your projector with a relay?
>Come to think of it, why don't you just get up and switch it, how often do you
>play a DVD and don't you have to get up to put it on anyway?
It's the challenge of getting it to do it automatically , Rocky
Comparing the presence with the absence of video is relatively easy ,
the complexity depends on the degree of the required precision, the
percentage of degradation on the video signal that can be allowed ( if
Also when the signal is not there is it replaced by noise ? If it is
, then , are you prepared to built a board that will include a couple
of video amplifiers two sync separators, a comparator , power supply
, connectors etc ? This will only detect the presence of video . Not
the sameness of the program.
Rocky has a point
Can you sense the power ON on one unit to operate a video relay ?
Some units have a switchet outlet at the back. than could be used to
operate a relay or you can built a current sensor to operate the