Yunmei alarm clock

  How do I tune the radio? FM broadcasting is the use of  frequency modulated radio waves  to transmit program content. The so-called frequency modulation is the frequency of the high-frequency signal with constant amplitude and constant frequency, which changes with the amplitude of the modulated signal. FM radio is to receive these frequency-modulated radio signals and restore them to sound waves after demodulation. The FM signal propagates in a straight line, so the coverage area is smaller than that of AM, SW and LW, but the signal quality is higher, so both TV and stereo broadcasts use FM. There are AM and FM bands on general radios or tape recorders. I believe everyone is already familiar with them. These two bands are used to listen to domestic radio. If there is SW band on the radio, in addition to domestic shortwave radio, you You can listen to radio programs from all over the world. In order to give you a better understanding of the use of the radio, the followi...

  The  clock radio  is the receiver of radio broadcasting. The weak signal of high frequency modulation input by the receiving antenna is converted into audio signal through method, frequency conversion and detection. According to different needs, the radio can be combined with different components and wiring methods. Earlier radios used electronic tubes, but now transistors and integrated circuits are commonly used. A regenerative radio with a simple circuit only needs a transistor, while a superheterodyne AM FM radio with a complicated circuit often uses a variety of integrated circuits. How to enhance the signal of FM radio The city is a reinforced concrete structure, plus the shielding effect of the steel bar in the ceiling and floor, so the signal is not very good. The clock radio receives FM and short-wave signals. It uses the attached whip antenna. You can drag a flexible wire indoors, scrape one end and connect it to the antenna to enhance the signal. If possible,...