This infrared tranmitter is intended for use with this infrared receiver.
It works with 2 – 1.5V batteries or a 3V lithium battery. To give a compact infrared device assembly and still a good frequency stability, the circuit uses a oscillator with outpashing network. Current consumption depends on power supply and duration as S1 remains pressed. When Ub = 2V, the frequency is 29.3 kHz, the LEDs top current is 25 mA and total current consumption is 27 mA.
When Ub = 3.2 V, freq is 30.4 kHz, the top current through each led is 64 mA and total current consumption is 67mA. At this voltage the distance between receiver and transmitter prototype was 13 meters.
Current consumption may be reduced by connecting with S1 in series a parallel group RC (R = 10 k Ω; C = 1000uF/6.3V).
By pressing S1 result only a short current impulse. Even if S1 remains pressed, the current can not exceed 300uA.