Electronic Guru's please - Extending a power button cable

DJMK4

DJMK4

DJMK4

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Hi all,

I am posting this in here as it might rack some minds of electronic guru's, plus I dont seem to be getting any response in other forums

What I am doing is mounting a laptop motherboard that I have in to a DVD case, and making a wifi media streamer.

I am planning on using the power button on the front of the DVD player to power the laptop components.

The laptop power pcb is quite small in size, and has a tiny ribbon coming off it which slots in to a little slot on the motherboard, I could in theory mount this small PCB behind the button on the front of the DVD player, however due to the ribbon only being 4cm long, I dont think I am going to have enough length.

is there a way I could mod this, and maybe get some wire and do a solder job to a button on the front of the DVD player?
 
I think its about 4-5 very small wires, there is about 4-5 pins on the end, I will try and get you a picture now of the power pcb
 
power.jpg


There you go, thats all it is
 
I'd guess that 2 of these wires are actually the switch, and that the 2 others go into a LED in the power button.
Figure out which two are the switch wires (If all else fails, short them- All a power button consists of is a passing contact switch), and connect these two to the power button from the DVD player.

-Leezer-
 
You could probably cut the ribbon off, desolder it and then solder new wires onto the contact points. It might be easier than soldering onto the ribbon.
I am confused what you are doing, are you planning on hooking the laptop ( in the dvd case) up to a TV. How do you plan on doing that?
 
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No, I have the motherboard and all the internals from the laptop, as the laptop screen and plastics were knackered, however the dual core laptop boots fine.

It's just a small unit to stream films from as my main PC I dont really like on all the time as its noisy.

More of a slow project really, as I like making things out of stuff I have lying around.

More info on identifying the two switch pins would be good, I am not sure how to identify them by "shorting" them
 
DJMK4 said:
No, I have the motherboard and all the internals from the laptop, as the laptop screen and plastics were knackered, however the dual core laptop boots fine.

It's just a small unit to stream films from as my main PC I dont really like on all the time as its noisy.

More of a slow project really, as I like making things out of stuff I have lying around.

More info on identifying the two switch pins would be good, I am not sure how to identify them by "shorting" them
Click to expand...
Ahh k, are you sure it can book without the screen?
 
RomanNose said:
Ahh k, are you sure it can book without the screen?
Click to expand...

Yes as it hooks up to my 24" monitor via the VGA or HDMI cable, I have had the motherboard layed out on my desk and it booted in to windows fine.

Just need to find a solution where I can easily switch it on.
 
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Ahh k, I just thought that most laptops require you to go into windows and enable the display. Anyway, I think it would be easier if you just took 2 wires from the laptop motherboard to the dvd button. You can then just use a multimeter to see which one of the wires is carrying the voltage, then just solder the two wires to the switch. I don't think it matters which way it goes around though so you can probably skip the multimeter step.
 
I have heard of people using two wires from some CAT5e, do you think this should suffice as I have some at home. I can test this tomorrow then when my DVD case arrives
 
DJMK4 said:
I have heard of people using two wires from some CAT5e, do you think this should suffice as I have some at home. I can test this tomorrow then when my DVD case arrives
Click to expand...

Should be fine as long as it's diameter is small enough. How long does it need to be, as a well known electrical store does 10m for £2 which is quite a good size for doing small scale electronics.
 
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I have the cat5e cable at home, I can just splice the outer core and strip out two wires, but I am going to need somewhere to solder them on, as the end of the ribbon is the copper pin's, then on the PCB side is a white slot where the ribbon slots in to.
 
If you are going to do it, then why not do it properly.

Get some veroboard, a through hole FFC connector a switch and make up a replacement board designed to do exactly what you want.

If you look around you might be able to get some FFC cable of the required length and use the existing board.


[edit]
Did a quick look on RS as you can get 15cm cables for about a pound, just make sure you get the right pitch and contact length.
 
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Rather than trying to figure out which wires to use on the ribbon, just wire a push button to the pcb contacts of the switch itself.
 
DJMK4 said:
I have the cat5e cable at home, I can just splice the outer core and strip out two wires, but I am going to need somewhere to solder them on, as the end of the ribbon is the copper pin's, then on the PCB side is a white slot where the ribbon slots in to.
Click to expand...

Ahh k, you might be able to look up the motherboard on the internet to find which pin does what. What does the white slot look like as you can get connectors like this.
pFPTyl.jpg

I don't know what they are call though, they are pretty useful and I need to get some more ( notice the soldered wire on the pin lol).
 
neodude said:
Rather than trying to figure out which wires to use on the ribbon, just wire a push button to the pcb contacts of the switch itself.
Click to expand...

So have wires from the push button on the DVD player joined to the PCB contact that was with the laptop?
 
at the back of the power button there will be 2 contacts, solder some old pc fan wire or speaker cable e.t.c to both contacts and then you can mount a switch to those wires.
forget soldering to the ribbon and using single core cat5e :\

simplez
 
RomanNose said:
Ahh k, you might be able to look up the motherboard on the internet to find which pin does what. What does the white slot look like as you can get connectors like this.
pFPTyl.jpg

I don't know what they are call though, they are pretty useful and I need to get some more ( notice the soldered wire on the pin lol).
Click to expand...

No he wont have a box header as its a laptop and from the picture hes provided its clearly a FFC (Flexible Flat Cable) The connecters on both PCB's will be sirface mount offering little or no space to hand solder.
 
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