Get LCD to turn on at same time as PC? 
Posted: 20 June 2010 10:41 PM   [ Ignore ]
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I want to get my LCD to turn on the same time i turn on my computer.  Ideally if there was a way to wire the power ON to the power button for my PC.

Anyone have any ideas how to pull this off?

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Posted: 21 June 2010 04:55 AM   [ Ignore ]   [ # 1 ]
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if you keep your LCD powered on but in standby mode, would that solve your problem? Or maybe your LCD does not do that. Just a thought.

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Posted: 21 June 2010 06:14 AM   [ Ignore ]   [ # 2 ]
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You could solder some electornics and make it work.

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Posted: 25 June 2010 09:39 PM   [ Ignore ]   [ # 3 ]
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I think soldering would be what i will need to do, just dont have any clue where to begin.

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Posted: 30 June 2010 03:34 PM   [ Ignore ]   [ # 4 ]
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AFAIK all lcds have a standby mode. The unit checks for a v-sync and if none is detected (cos the pc is off) then it enters standby (usually shown by an amber lamp). When v-sync returns the LCD powers on and locks to the signal to display an image. What makes you say electronics is the way to go? If it is I can help you with a basic circuit.

Update: if you’re referring to an LCD tv then things are different from a pc LCD. The unit should still enter standby if left long enough without a signal. The problem is it will not automatically come back on with the video signal. Also when it is switched on with the remote it will probably default to a tv station and not the hdmi input connector. You’ve got 2 different problems there.

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Posted: 30 June 2010 07:45 PM   [ Ignore ]   [ # 5 ]
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I did a quick workaround for the same problem on my setup. Its not the best but it works.
I wired the Power supply of the PC and the LCD to the same AC Connecter which has a switch and bridged the Power switch of the pc so it automatically turns on if you switch the ac power on.
So i just have to switch on the AC power and the PC and LCD start at the same time.
Quick and easy, although not ideal.

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Posted: 01 July 2010 01:14 AM   [ Ignore ]   [ # 6 ]
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...from a totally different angle....have the pc on 24/7 but running just the most basic blob identification keeping CPU usage to a minimum and with the LCD in standby. Power usage might be around 50w for the pc. A single touch will bring the LCD out of standyby. The result would look great but of course standyby power is too high for most tastes but at least the power hungry (42”?) LCD would be off. Or even bigger savings for a projector.  Any other low power ideas for detecting a single touch?

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Posted: 02 July 2010 05:38 PM   [ Ignore ]   [ # 7 ]
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Payne, how did you get the LCD to turn on as well.  I get connecting it to the same AC connector but once u cut the power to an LCD and turn it back on, from my experience you still have to push the “On” button on the LCD.

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Posted: 02 July 2010 05:52 PM   [ Ignore ]   [ # 8 ]
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If the LCD is turned on and i disconnect the AC Power and plug it in, it starts automatically with the settings before the shutdown.
Also the LCD in my Living Room does that but i don’t know how it is for LCDs from other brands.

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Posted: 02 July 2010 07:42 PM   [ Ignore ]   [ # 9 ]
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I use dynex but when I turn off the power strip which my psu for the computer as well as the lcd connects to, after turning the power strip back on my lcd definitely does not turn on. Unfortunately.

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Posted: 03 July 2010 02:44 AM   [ Ignore ]   [ # 10 ]
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thats bad =(

Other Idea:
You could use a IR dongle on your PC and write a little program to turn on the LCD. (would be an easy way without soldering).
Or you could make a little transistor switch on the 12V or 7V line of the PSU (The circuit to switch wouldn’t be much of a challenge but as long as it should be a switch the signal must be reset after switching on and i don’t know how you can achieve this easily).

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Posted: 03 July 2010 08:07 PM   [ Ignore ]   [ # 11 ]
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Ok I understood the ir dongle approach. First question is what is a good ir dongle for programming.

The other suggestion about the Transistor I didn’t understand is there a product page u can send me to illustrate or can u go more into detail. Thanks

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Posted: 04 July 2010 02:53 AM   [ Ignore ]   [ # 12 ]
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You need a logic device that will generate a pulse on the rising edge of one of the v-outs of your psu. Use this pulse to drive a mosfet which is in turn used to switch on the LCD. You’ll need 2 or 3 components and a soldering iron. This method assumes that the LCD is ready to be switched on immediately after the power is applied and without any delay. And you can’t know if this will work until you’ve tried it. Otherwise you’ll need to modify your circuit and start adding delays.

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Posted: 04 July 2010 02:57 PM   [ Ignore ]   [ # 13 ]
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To use a PC as IR Remote i used only a small circuit with an IR led connected to the parrallel output of the pc with a little c programm.
I searched for the link but didn’t find the circuit anymore but it is quite easy to make, just some googling.

The Method kingtolo mentioned is exactly what i was thinking of wink
If you need a delay you can easily achieve this with a 555 timer IC.

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