electronics newbie needs answers

davidclayton

hi there,

i'm setting up a custom case for a pc.
i need to know what type of switch i need for the power on/off on the front.
[don't need a reset switch]
is the switch needed a:

-push to make
-push to break
-locking push


i also need to know what type of LEDs to get for the power/hard drive activity




all help appreciated.
dave

gobby

Originally posted by davidclayton
hi there,

i'm setting up a custom case for a pc.
i need to know what type of switch i need for the power on/off on the front.
[don't need a reset switch]
is the switch needed a:

-push to make
-push to break
-locking push


i also need to know what type of LEDs to get for the power/hard drive activity




all help appreciated.
dave

Couldn't be 100% Dave. Your best bet is to test what type of switches/LED's are in the case that you already have.

The switch shouldn't be too difficult to test. (You could always borrow my multimeter). I would imagine it is a push to make. If it was a push to break then there would be a hell of a lot of wasted power!

As for the LED, I wouldn't be too worried bout that. LED's can be quite robust and arn't exactly the most expensive things in the world. Buy one, set it up, if it's too bright well then consider getting one with a different current rating.

Best of luck dude! (btw, Have you ordered everything yet? E-mail me.)

davidclayton

sorry to be a bitch gob, but...
that was no help whatsoever.
i still don't know what switch to use,
or even what LEDs.

i've experimented with LEDs unsuccessfullly before,
i'd prefer to know EXACTLY which ones to get, rather than frying a few.

i'll email you to bitch some more.:D

quarryman

Originally posted by davidclayton
hi there,

i also need to know what type of LEDs to get for the power/hard drive activity


all help appreciated.
dave

this is a guide for the xbox but it shouldn't be much different for you and probably even easier since you'll have a HDD activity line somewhere on the mobo.

according to the guide you need a

6v
20mA LED



and a

220Ohm resistor



this will prob do the trick for the LED.

this for the switch.

Raz

You'll just need your average run of the mill LED. You would need a special LED if it was to be controlling the flow of current in a circuit but this just needs it to light up and switch off when there's activity. Something with a 3 or 4mm diameter. Blue are more expensive for some reason.
There's probably a standard for ATX. See if you can find an ATX specification and that might give you the exact requirements.
Edit: Here's an example of the LED's I used when replacing some on the front panel of my PC,
Thumbnail
Large ~1mb
In fact just go here or here to see the list of images.

As for the switch, I'm not familliar with the different types but going by the names, push to make and locking switches seem to do the same thing except the locking doesn't pop back out.
Seeing as mobos power off automatically these days it will only be used for switching on the board. Therefore it will only ever be making the connection and not breaking it so I'd say a push to make would be the one necessary.

Edit: Do you have a multi meter you could use to check the current coming from the mobo?

davidclayton

do i need an LED only, or resistor aswell,
or does it depend on the current from the mobo?

i don't have the mobo yet.
its this one:
http://www.cartft.com/shop/catalog/il/63

quarryman

some leds need a resistor some have it bulit in. you just have to read the specifications. if you go to the led page on peats it'll give you a list of leds that show you whether they need resistors or not.

here's another guide for leds.

davidclayton

ok
i see 12v ones on peats that have built in resistors.
but how am i meant to know what the voltage [or current] is coming from the mobo?

here's the spec sheet for the mobo, but it doesn't mention what i'm looking for.
http://www.viavpsd.com/product/3/4/EPIA-M_v1.40.pdf

davidclayton

you know what would make this a whole lot easier?
if you could buy generic front panel switched/leds already mounted on a pcb.
but i guess that's asking for too much.

when i think of all the old cases i've thrown out.
i could have ripped out the front connections...

anyone have a decrepit old case they don't need?
so i can rip out its innards?

quarryman

i do.

i ripped the switch out of my old dell. it has a connection to the mobo that powers the power and HDD activity light as well as the switch.

€48 ONO.*


*free

davidclayton

WWWOOOOO HHHOOOOOOO!