The wireless microphone is divided into three frequency bands, FM, VHF and UHF. The following briefly introduces the functions and applications of each frequency band. Duan: We all know FM radio. The frequency of FM radio is 88-108MHz. The frequency of wireless microphones in the FM band is higher than 108MHz. Generally between 110-120MHz, so the signal of FM radio station will not interfere with the wireless microphone of the FM band.
However, it will be disturbed by other clutter; the advantages of wireless microphones are: simple circuit structure, low cost, which is conducive to the production of manufacturers; disadvantages: poor sound quality, frequency will change with time/environment temperature changes, and often show poor acceptance , The situation of disconnection was greatly disturbed. Screaming into the microphone will cause staccato.
Application occasions: The application requirements are very low, and the sound quality is not much required. FM wireless microphones can be used in situations where only sound is required. The function and common sense section of various frequency bands of wireless microphones is abbreviated as V section, and the frequency is between 180-280MHz.
Due to the high frequency, there is generally little interference. The frequency lock of crystal is selected, and the condition of frequency conversion will not appear, and the reception function is relatively stable. V-band wireless microphones generally have two circuits: the high-frequency part uses only a 2003 integrated IC. Including. Signal acceptance, radio frequency amplification, frequency mixing, frequency discrimination, etc. are completed in one step. Sensitivity is not high, 31101 line is used for audio part.