LEDs at home

Very quick 2 questions!

1. Any idea for making light on/off LED indicator (ie. I turn my patio light on, and LED inside the house goes ON)?

2. how can you connect LED to 120VAC with no transformator?

ekrzys wrote:

Very quick 2 questions! 1. Any idea for making light on/off LED indicator (ie. I turn my patio light on, and LED inside the house goes ON)? 2. how can you connect LED to 120VAC with no transformator?

As far as i know LED's are for DC power only...although i have used white LED's in my alarm clocks night light that took a AC 12v bulb.

I truthfully dont know

You can't.

seeing that LEDs can only run off of DC voltage and your house is AC, so first you have to convert it from AC to DC then you have to either get a bunch of resistors that will bring it down or a single one, but they will get real hot if you use one. There are ways to do it, but I don't work with AC so my way is the only I know of.

send a PM to Adrian here on the board and he might be able to help you out with that.

if you want an idicator for the porch light get a 120vac neon indicator lamp
check www.allelectronics.com they have em.

ekrzys wrote:

Very quick 2 questions! 2. how can you connect LED to 120VAC with no transformator?

Just touch the + wire to the + terminal, and the - wire to the - terminal, and wait for the huge POP as it blows! (and probably explodes...)

Transformers are pretty cheap and easy to get. Either a computer power supply, or one of the plug-in "bricks". You can get those with variable voltage, so you can match up with the voltage your LEDs want, or get a 12v one, and use resistors so you could also plug in other car lighting.