What's the most efficient way of powering a back-lit sign?

[sparkly]

disclaimer: I'm a big electronics newbie.

I'm trying to make a backlit sign in my room. The sign will have a siwtch and will be able to be plugged into the wall. I'm using 2 cold cathode tubes ( **broken link removed** ). I know I'll need to have some sort of DC power source, but this is going to be outside of a computer, so whatever power source I use wont have the standard molex connector of a computer power supply to power the lights. So, what is the most efficient way of powering the lights? I'm going to need somewhat of a long cord for the power as well. I'd also like to have a switch for them.

bonus: If the lights can sort of pulse or shut on and off while the switch is ON that would be awesome.

Thanks!

 

[flatulent]

Re: Backlit Sign

The lights take 12 V DC. You can get this sort of power supply at places like Tandy/
Radio Shack. You can make the lights turn on and off by having a relay between the 12 V and the light and use a 555 timer to control the relay.

 

[sparkly]

Re: Backlit Sign

Well, I know I can just get a 12VDC power supply, but those usually have a round connector type on the end...do I just cut that off and use the wire or do I do something else?

 

[flatulent]

Re: Backlit Sign

At these low voltages you can just cut the plugs off and solder the wires together and wrap them with insulating tape.

 

[sparkly]

Re: Backlit Sign

okay, is it going to be a 12VDC/ 5mA dc power supply? Also, I looked at the 555 timer and it looks fairly complicated...how exactly do you set that up in series with the switch and the relay?

 

[sparkly]

Re: Backlit Sign

OK--so the 555 is too complex for what I need. What sort of relay should I use if I just want to have the light blink once or twice per second?

 

[flatulent]

Re: Backlit Sign

You should look into a ready made device. Lights on Christmas trees sometimes use these.

 

[sparkly]

Re: Backlit Sign

I have one last question. Does the 12VDC power supply's amp rating matter? There are so many to choose from...

 

[flatulent]

Re: Backlit Sign

Your light draws 5 mA so any supply rated over 5 mA should work.