VHF Directional receiver

摘要: A miniature handheld receiver contained in a metal shielding enclosure incorporating slot type directional antenna as part of the structure such that when is aligned with radio frequency signal interest, null produced level. The coupled to circuitry which includes an oscillator used FM modulate by tone injection unmodulated carrier present, detector for demodulating RF signal, audio amplifier amplifying demodulated and acoustically earphone prevent stray pickup from cord.