With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Fahrenheit 451 is a dystopian fantasy film.
text_B: A product detector is a type of demodulator used for AM and SSB signals .. demodulator. demodulator. amplitude modulation. SSB. Single-sideband modulation. Rather than converting the envelope of the signal into the decoded waveform like an envelope detector , the product detector takes the product of the modulated signal and a local oscillator , hence the name .. envelope detector. envelope detector. local oscillator. local oscillator. A product detector is a frequency mixer .. frequency mixer. frequency mixer. Product detectors can be designed to accept either IF or RF frequency inputs .. Intermediate frequency. Radio frequency. A product detector which accepts an IF signal would be used as a demodulator block in a superheterodyne receiver , and a detector designed for RF can be combined with an RF amplifier and a low-pass filter into a direct-conversion receiver .. demodulator. demodulator. Intermediate frequency. Radio frequency. superheterodyne receiver. superheterodyne receiver. direct-conversion receiver. Direct conversion receiver
not_related.