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video composite spliter Answered

Hi, i have 3 portable(car) monitors that take composite video signal in, the deal is i want to link them all together to the same source..
Can i simply daisy chain them(parallel) or do i need some kind of amplifier to do the trick?
If so, please provide a tutorial/instructable on how to make one..
The source can be s-video, vga, or any standard computer video analog output.. i'm not saying dvi or hdmi interface due to the fact D/A conversions being not that simple(for me)..(but please provide the schematics anyway)

I'm sorry for my terrible english x)

Best regards,
Fábio Santos.



7 years ago

^Thanks i'l try that!
Another issue is the power supply for all 3 monitors..
Each one needs 9V/1A(at least is what is written on the labels)
I will use a computer psu (for now) to provide all the power, since it can pump out high current and i have plenty of those..
So, the 12v rail can put about 20amps max, and was thinking of using the lm350t that is a variable voltage regulator, to limit the 12v to the 9v required..
Now since i want to power all 3 monitors at the same time and from the same source, should i simply parallel them to the output of the regulator, use 3 paralleled regulators (no need for such high amperage regulator in this case) 1 for each monitor, or all this is just a really bad idea?

i'm far from expert on this, just a curious that wants to learn x)


7 years ago

I have had great success splitting video into 2 lines. I just place a 75 ohm resistor in each output wire (in series). I have never done it with 3 outputs, but it might work. Adding the 75 ohm resistor might help keep the 3 monitors from pulling down the video voltages. If that doesn't work, then you will need a video amplifier with 3 outputs or more. Radio shack sells them, but they are not cheap.


7 years ago

For just three monitors on a relatively short run, you can probably get away with just soldering them together. I think if your lines run very far or if you add any more monitors you'll likely need to add an amplifier. It never hurts to try, and if it doesn't work, just pursue one of your other options.


Answer 7 years ago

I was just afraid of burning something..

Thanks for your help =)