IR Jammer circuit not working

The major problem is that the current through the LEDs is going to be limited to about 3mA

Once the voltage across the 180 ohm resistor exceeds about 0.7V, the 2 1N4148's shunt any additional current away from the base of the transistor.

Are you sure the resistor isn't meant to be 18 ohms?

Even with 18 ohms, the light output isn't going to be significant enough to jam IR transmitters unless this device is placed right next to the receiver. And if you're going to do that, a piece of black card would be more effective.

 

If you remove the resistor entirely, either the transistor or the LEDs (or possibly all three) will join the great electronics project in the sky.

The LED current will be limited to approx 0.7/R Amps (or 700/R mA).

If these LEDs are rated for 20mA then you would be safe setting the resistor for 30mA.

Note also that you have an unlabelled pin on your 555. It should be labelled as pin 7

47 ohms gives you about 15mA.

To get any significant range you would need to have a very short duty cycle and have the LED current much higher (but averaging 20mA or less). The datasheet on the LEDs would tell you what current you can use for a given duty cycle.