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Lets' start with: What are you trying to signal/control with the IR?
At what distance minimum? I'm seeing 10m tossed around, AudioGurus' got it: at these duty cycles you can pump a Lot more power into the IR LED.
I've done the 555 as carrier but was gating the pattern with a micro. It was 1 LED with 47 ohms and 16+ volts for it & the 555. Worked fine to ~15', but that was 1997... <<<)))
The way to do this is use a crystal oscillator and divide the frequency down to 38 Khz at a very small duty cycle.
You can then safely pulse maybe an Amp or so through the LED if the duty cycle is made short enough.
That takes care of the transmitter.
The receiver needs to be very precisely tuned to the exact same 38 Khz pulsing transmitter frequency, and you can do that with either synchronous digital sampling, or analog techniques.
By only being sensitive to the exact 38 Khz transmitter switching frequency, it will eliminate all ambient lighting interference and noise problems, and you can use really high gain in the receiver.
It then works exactly like a tuned narrow band radio receiver, but working at infrared.
There is nothing new or revolutionary about any of this, some commercial intruder beam alarm systems work on this narrow band tuned reception principle to span very long ranges day or night.
The secret is accurate timing at both ends. If you want an operating bandwidth of maybe only a few Hz, your frequencies need to be that accurate at both ends, and only a quartz crystal oscillator will give you that.
You don't need such a big transistor, and the LED's and limiting resistor should be in it's collector (not the emitter), with the base fed via a resistor. You also need a decent size capacitor across the battery, which will greatly extend it's life. As it is, it's a really poor example of an IR remote control.
You might check the IR circuit from my PIC tutorials for an example.
Simply ignore the receiver part (the IC), the transmitter side connects to a PIC which generates the required signals, similar to post #25 above (but done correctly).
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