Electronic switch for selecting satellite polarization signals

Claim 1

An electronic switch used in a low noise block down converter (LNB) for controlling the reception of satellite polarization signals, said electronic switch comprising: a pulse width discriminator for comparing widths of an input signal with a reference width to output a pulse with a pre-determined frequency and a 0 V signal according to the comparison results, respectively; a latching means for receiving said pulse with a predetermined frequency and said 0 V signal from said width discriminator to output a high voltage and a low voltage to a FET selection controller, respectively; and said FET selection controller comprising two switching FET circuits respectively connected with a horizontal probe and a vertical probe and a complementary element; said complementary element receiving the outputs of said latching means and outputting two complementary signals to said two switching FET circuits so that only one of said FET circuits is turned on at a time, whereby selecting a desired polarization signal.