i am using infrared to control a project, but i cant seem to get data sent father than ~36in (~91 cm). i am using an NPN transistor as a data switch for the led to raise the voltage from logic level to 5v. i am using an Arduino Nano. here is a photo of my setup:
is there any way i can increase my range to 4-6ft (~122 - ~183cm)
(p.s. im working on a schematic right now so please dont hassle me for one)
The way to increase range is to increase current through the LED.
The LED data sheet will tell you the maximum pulsed current and the duration of the pulses.
You should easily get 4 to 6 feet. I have seen people claim 30 feet with 50mA or more LED pulsed currents.
Or you can drive two or more emitter circuits (led with its own series resistor ) in parallel with each other with the drive transistor.
I get about 20 feet.
as in connecting four total leds, divided into two sets of two, each connected to the left pin of the transistor and each with its own 1K ohm resister?
Why 1K? That gives only a few mA to the LEDs with 5V supply. If you want more range you need more current. Lower value resistors give more current. . The LEDs are likely good for 20mA continuous and over 50mA pulse.
Post a data sheet for the LEDs
What supply voltage are you using to power the LEDs?
I assume this is for modulate (38kHz) IR remote control.
Which thransistor.
Is the emitter connected to ground.
What value base resistor. Should be about 470 ohm.
Most IR LEDs can handle 100mA continuous and more than 200mA peak.
Try a 22 or 33ohm series resistor for two LEDs in series.
Three LEDs in series might be pushing it.
What is your external supply (voltage).
Too high, and your Nano could burn.
Leo..
If you're sending and receiving photons then optics comes into the picture.
A transmitter mounted in a flashlight reflector and a receiver mounted in a similar
way will focus more photons toward the receiver and more photons from the transmitter. Get a couple of cheap flashlights that have reflectors and try it yourself. I got about 20 or 30 feet when I did that but the reflectors were about
6" in diameter. A lens in front of them helps too. I'm not an optics engineer so
I couldn't tell you how to use cheap magnifying glasses and flashlights to fabricate transmitter and receiver housings but that seemed to make a difference when I built one about 35 years ago.
Don't know what OP is doing, remote or beambreak,
but two 100mA IR LEDs without optics can bridge 50m (150ft) in broad daylight.
Leo..
without a schematic we don't know how much current he's using.
Having all 3 LEDs in series is going to reduce the current sent through each of them. Wire them in parallel and you'll get probably 3 times the range.
See post#4. Two in series is perfect on a 5volt supply.
Vf of an IR LED is about 1.4volt on a medium current.
Leo..
I didn't know what to put, so that's what I grabbed. (Lucky Dip!)
5v
the listing also says that they are 80mA
NPN
yes
2 220's (so a total of 440, i dont have a 470 laying around sadly)
The lowest I have is a 220. i will look around on some spare circuit boards, but i doubt i would find one.
it is a consumer product so im rating it for 6-12v, should i narrow this range?
How would i do that? My tools are limited to an analog multimeter and a nano.
Could i possibly get the schematic for that?
Can't open the schematic image
fixed
Measure the voltage drop across the 1k R3 resistor so we know the current
