Want to put LED Display on Dashboard

got Radio Shack and get a flashing RED or any other color LED that's 12 volt attach to wires to it, put a switch on the positive wire, and hook it to something that's constant 12 volts with engine off.

At Autozone they have this fake alarm LED that plugs into the 12V lighter socket. It flashes pretty bright.. it costs like $4.

And afterwards, watch it go up in smoke! You're going to need a current limiting resistor. At 12V, say.. 20mA with a 2V drop, roughly 500 ohms would be good.

That might be easier. So it'll only work with the key on?

-Tim

"Tim H." wrote in news:p6qmb.10236$mZ5.63271@attbi_s54:

On many cars, the lighter socket works with the key on or off. But if it doesn't work with the key off, he could cut off the plug and wire it directly to something else that stays on.

Hmm, looks like we're back to the RadioShack $5 blinking 12v LED ... which I have successfully used in several cars - even ones with alarm systems. They're cheap, work well, and look like an alarm indicator, not just a flashing lamp.

PoD

Make sure & get one of those cool window stickers that says "This car protected by this sticker".

:-)

-Jeff Deeney-

Approximately 10/25/03 20:56, Joseph A. Zupko uttered for posterity:

LED's do not flash. The only way to make an LED flash is to add small control electronics to a normal LED. If you buy a 12 volt rated LED flasher, it will work at 12 volts with no additional parts or resistors.

You can also buy a standard LED and mount it in a small grommet in your dash, but it won't get as much attention as a unit that flashes. Again, if the Radio Shack description of the LED is that it is for a 12 volt circuit, it needs no external resistors.

Stay with that, as otherwise you will learn more about LED characteristics and voltage and current than you probably cared to know... not to mention you'd also need to learn how to identify the polarity of a "naked" LED.

1,000 ohm, 1/4 watt -- Brown Black Red, don't worry about the fourth band. Most common resistor made.

Bulldinky. This LED flashes just fine.

Wire it in series with a 470 or 330 ohm resistor and you're set. (470 is the recommended value, I use 330 for a little more brightness)

Dan

Approximately 10/26/03 17:54, Cantide uttered for posterity:

Like I said. LED's can not flash, do not flash, and would not even flash if you bought them the trenchcoat. I am sorry your puny little brain insists on posting without either a fact or a clue, but you are still wrong. As noted above, the ONLY way to make an LED flash is to add control electronics to that LED so it will flash. If you had a brain and any electronics education whatsoever, you would be familiar with the internal functioning of a simple light emitting diode. You might, if you studied long and hard to come up to electronics idiot levels, [e.g. a journalism major level of grasp of concept] know just how trivially easy it is to put a simple electronic timer function inside the same housing as that of the LED.

But thank you for playing, and exposing just how horrid the state of education in the USofA is....

People like you get SO pissy when you're proven wrong! Mr. Zupko doesn't give a whit whether he's buying a pure standalone LED or one with a 555 timer on the same lil bit of silicon. He just want's a damn flashing light, but anal retentive twits like you can't leave it at that. Nooooo, you've got to go into sematics of whether a LED with an integrated timer is still a LED. Just give the guy a friggin part number and stop being such a prick.

Dan

Approximately 10/26/03 19:04, Cantide uttered for posterity:

Your stupidity is exceeded only by your inability to recognize it. Worse, the poor original poster can buy a small LED that comes complete with not only the timer but protective circuitry suitable for the actual voltage ranges found in an automobile. This can even be had complete with a mount that snaps into a standard dash hole and offers standard automobile spade terminals.

Now please go play with your big sister and stop pretending to know something you haven't a clue about and continue to give bad advice concerning. And no, a 555 chip isn't needed.

Hint, enter in your favorite search engine: [ automobile flashing led ]

Some of them even come with the little fake stickers and the little signs that make it look more like a real alarm LED.

The original poster is recommended to enter just those words and pick the one that suits their budget and ability to install, plus whatever decoy material is also desired. *You* are invited to byte me.

The radio shack LED with embedded timer for blinking isn`t very good. The `on` time is too long and appears unprofessional. Also, it will not go as bright. I`d tried super bright blue/red/clear with timer. Didn`t like em` except the red one. So I made my own with:

1. A LED from a kid`s shoe. (Made in China)
2. A junk timer from a Honda clock.

It`s spectacular and free! Rick