Remote control electronic firecracker circuit

Circuit working principle: Infrared emission circuit (Figure a)
consists of three parts: oscillation, shaping and modulation emission. A typical
CMOS multivibrator is formed with CD4011 as the core, and its oscillation frequency is f0 =1/[2.2 (R2+Rp')·C]
(where Rp' is the actual setting value of Rp), where Set f0 to 40 kHz. The oscillation output
waveform is shaped by the internal and non-f J of CD4011 and then drives the modulation transmitting circuit to control the
operation of the transistor VT1, so that the infrared emitting diodes LED1 and LED2 emit infrared
control signals of about 40 kHz.