Led

[tyguy2021]

Me and a freind were trying to make a led Ir light conect to a responder so when the light is picked up it turns on a small dc moter. for some reson it didn't seem to work. help

[KenWittlief]

you have supplied no information on what parts you used, what sort of motor you are trying to power, the distance involved, power supplies or batteries available...

If you are learning this from scratch you might try one of the experimenter kits from Radio Shack, or stop at your library and pick up a book on the subject.

It would be very difficult for anyone on this forum to design your circuit for you, because we have no idea what you are trying to do.

[tyguy2021]

first - i don't want my circuit designed for me

second -its just a small 3v moter from radio shack and we had the responder working as a switch and the current was going Though and powering the moter. We were trying to get it to turn off with the LED.

third - the battery for the moter circuit are 2 double A's the LED was being run off a triple a.

forth - they only need to be spaced .75 in apart

[sciguy125]

First off, what's this responder you speak of? Is it some circuit you built or is it something you bought? We need some details on this.

I'm also not sure what exactly your problem is. You said that the motor is being powered. What's not working correctly?

You mentioned having two separate power supplies. This implies that you have two seperate circuits. I'm going to take a guess and say that you have some sort of transmitter and some sort of reciever. It sounds like your transmitter is some sort of IR LED circuit. And it sounds like your reciever is some sort of IR detector that turns a motor on when it sees the LED. Is this correct?

[tyguy2021]

yes thats correct, we had the power running though then we where gong to try and have it pic the LED up and shut down the moter.

[KenWittlief]

can you draw up your circuit and post it here as a pdf or jpg (free pdf conversion SW at www.pdf995.com) ?

include the part numbers of the LED and sensor you are using.

My psychic powers must be a little off today, I cannot see your circuit or prototype from here :^)

[Cuog]

If i am correct u have two circuits one with a AAA battery and an IR LED,
--------problem 1 i think there is not enough power for that IR LED from one AAA and if u didnt use a resistor the LED might be dead now, go find the starts for that LED and post what the current draw is.

For the receiver, i think i may know what u are talking about it is a thing that has two or three little posts coming out of it and it looks like a weird LED, a pinout for that would be useful as well as a wiring diagram so that we are sure that it is all hooked up and going to work like u are hoping.

[Al Skierkiewicz]

I am going to make an assumption that you just connected the IR LED to the battery and hoped that it would emit. A second assumption is that you connected the motor the receptor and the batteries in series. In this case the LED lighting the receptor would turn it "ON" causing the motor to turn. LEDs are strange little devices that cannot control themselves when connected to a power source. An LED requires 2 volts to turn on so a single battery will not light it. An LED also needs some current limiting to prevent damage so you need to make a calculation to set the current to about 25 ma or whatever the design current needs to be. As to the photoreceptor you can think of it as a transistor with no base lead if it only has two leads. It would work best if you tie the emitter to the negative lead of the battery, the collector to one lead of the motor and positive lead of the battery to the other motor lead. The emitter will act as a switch, turning on when illuminated by the LED.
Now things will get complicated. If you purchased an IR detector module it may need to have a modulated beam from the LED. The remote for your TV uses a modulated beam to prevent things like the sun and lamps from affecting the remote commands. We really need to know what you are using. Part numbers and source.