IR Detector

In this Instructable I will show you how to make a simple infra red (IR) detector.
When your TV stops responding to the remote it is hard to tell if the TV is broken or the remote doesn't work. With this little pocket-sized gadget you will know.
Spying has become more and more accessible to the average man. Whit this gadget you can check if someone has installed a night-vision camera in you room or office.

First I am going to show you how to build it and then how to use it.

If you are just interested how IR remote control works got to step 7.

Step 1 Electronic Components

For this project you will need a couple of electronic components,all in total 3$.

1. Fototransistor (IR_Transistor);( in this chase I used RadioShack 276-0145);(picture 2)

2.LED

3.Micro switch.

4.330 Ohm resistor (picture 3)

5.An electronic solder board (holes)

6. 9V battery snap

7. 9V battery

8. Rubber band

(all of the electronic components can be bought at your local RadioShack)

Comments

[ondrikczech]

can i use led from tv remote as ir transistor?

[stephenniall]

WIll the red Led Flash to the binary code preset into the remote ?

Say if 1 is on and 0 is off If the code was 1 1 0 0 1 0 1 Would the Led go on on off off and so on

[372jpeg]

if you replace the led with a buzzer it would be pretty cool it be like beep, beep, off, off, beep, off, beep

[Goodhart]

With a buzzer, depending on what kind you refer to, it may need it's signal amplified or converted from a pulsed DC to a waveform (if the buzzer or beeper runs on low voltage DC, then you can ignore everything I just wrote :-)

[372jpeg]

i was thinking a low voltage one but thanks for the tip :)

[Goodhart]

Well, by low, I meant "very" low :-) There will be less then 3 v running through the LED, so it'd have to operate in that kind of environment

[comodore]

yup!  It's does just ask you explained!  

[electric_piano_5k]

I once took an old remote from a broken DVD player and took out the IR LED and soldered in a green LED. Then I could see the remote flash as I pushed the buttons. And if you wave the remote around, you can see the 1100101 patterns and you can see that they are different when you push different buttons. Of course only do this with a remote that you no longer need, not a good idea to do this just to find out if the remote is working!

[stephenniall]

Ahh thank you . Will be going to maplins tomorrow to buy the components for this

[comodore]

Good luck and keep me posted on how your project goes!   :)

[stephenniall]

will post a picture tomorrow if i finish it !

[Chowmix12]

is it tomorrow yet?

[comodore]

Great! Can't wait to see them!

[vectrasj]

All respects!
But You do not need to built this!
Reason:
- You have a mobile phone with camera (any format)
- Turn Your camera on mobile phone ON
- Point camera at front of remote (20-30cm)
- press button on remote
- if button send IR command You will SEE white beam from the IR LED!
- Repeat press all buttons on remote and check IR LED response !

MOBBILE PHONE CAMERA SEE IR LIGHT !

[Goodhart]

One reason TO make this is to have a seperate circuit to work with for other projects: sound sources, turning on or off other switches, etc with IR, ...there are a host of reasons TO build this; even if only to learn how it works.

[account3r2]

some people dont have a camera and i think this is a neat project

[dawsonj]

most cameras see infrared light

[Hycro]

I once had a stereo that if I were to hold the switch on my halogen bed lamp close enough to the on position that it would make the light flash, I could make my stereo open/close the CD drawer, or even change the volume, depending on how close or far the contacts of the switch were apart.

[comodore]

That is very interesting, I never heard something like that, but I can bet you there is a scientific explanation for it! Hmm, interesting, tell that to teck-king, he might have an explanation....

[Goodhart]

I wonder if one of the LED's isn't "detecting" the signal? That can happen, but normally only if there is a voltage already applied to the circuit.

[Arduino Guy]

possibly the halogen lamp emits a flickering ir signal (all heat consists of ir rays)from the mains 60Hz/50Hz and then the device gets "confused"?

[Hycro]

Sounds very likely...I didn't know then what I know now about that kind of stuff, though it's marginally more now...XD

[Hycro]

Oh likely, but it was still neat to do. I think the stereo that did it was the one I also blew the amp in...

[comodore]

Haha! How did you do that? :)

[Hycro]

I had so many speakers connected in parallel that the resistance went below the amp's tolerance, and since it was under warranty, I didn't take it apart to see exactly what happened, but it likely overheated, and probably didn't have an automatic thermal shut-down, I tried it the next day, and still didn't work. It was designed to use a 6 ohm speaker per channel, and I had 6 or 7 8 ohm speakers connected in parallel, thereby reducing the resistance, essentially shorting the amp, or even overheating it. That's another reason why I like the amplifier ICs for car stereos, they have internal short and thermal overload protection, and operate at anywhere from 11VDC to 18VDC without damage, though the manufacturer states the optimum performance is usually at ~13.4VDC to ~15VDC. (Manufacturer states that is the standard charging voltage for a lead-acid battery being charged by the alternator in the car.)

[comodore]

Well, I am a n00b in electronic, meaning I started to learn it not while ago..I understan, I think I do, what happened, it probably overheated, it was just too much for the amp to take... But, I know that in newer devices, by the IC, or a transistor, they put a thermoresistor, NTC, I think it is.... So if it gets over heated the resistance value rises and like a switch, cuts of the circuit...or a thermal switch.... :)

[Hycro]

Yea, most car stereo amplifier chips that I've researched have that capability.

[jack002]

I use my camera in my phone. You dont even have to take a pic, just look at the screen while holding the remote towards it.

[Goodhart]

This works with most digital cameras

[The Incredible IT Maker]

so............ does this mean in theory you could build an ir aray on any digital camera and have a night vision camera?

[Goodhart]

Yes.

[phevtron]

ok but whats the range? can be used to switch lights etc?

[Goodhart]

If you used a relay it might be possible.

[techno guy]

Isn't 9 volts a little too much for LEDs even if you have a 330 ohm resistor? Unless the ir transistor provides a lot of resistance.

[Goodhart]

It depends on the amperage rating of the source, the voltage drop across the LED, and the amperage rating of the LED.

[techno guy]

If it measures heat, then can you replace the red LED with an analog meter and measure heat?

[crtn2]

you can use 3V button cell battery to make this thing smaller.
(replace 330 ohm resistor with lower value for voltages <4.5V)

[account3r2]

please respond quick, what voltage do the leds need to be?

[The Incredible IT Maker]

usualy around 3 volts at the most

[MadScientist101]

wat stops it from sensing other light sources, why deos it only detect IR