博文

How is the radio tuned?

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  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...

How do I enhance the signal of an FM radio?

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  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,...

why 2021 cars still have CD players?

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  First of all, we have a conclusion that   CD players   are currently on the way to being eliminated. This is not just limited to cars, but innovations in storage media. CD is a storage medium. Essentially, there is no difference between CD and flash memory or even tape. The current CD is facing is the same as the original cassette. Just like the cassette player disappeared from the car, CD due to the low storage density and too large volume, I think it will be eliminated sooner or later. Just like non-smart phones before, when smart phones were invented, non-smart phones seemed to be invisible overnight. Record companies can use write-protected U disks or even SD cards to replace CD distribution. In the case of portable players, portable CDs disappeared a long time ago, and some problems can be seen from this point. As a storage medium, optical disks are used in large-capacity U disks and mobile hard disks have begun to decline after the advent of them. This can be refl...

Five best high-tech charging alarm clocks

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  Five best high-tech charging alarm clocks Now it’s 2021, and the update of alarm clocks is also very rapid. There are many smarter and more powerful wireless charging alarm clocks. If the old-fashioned alarm clock placed on your bedside is still a few years ago, then I think you should upgrade yours. Alarm clock, you need an upgraded and powerful wireless charging alarm clock. Many people will look for a charging cable to charge their mobile phone before going to bed. Then you can upgrade your sleeping time from now on. Some manufacturers who are good at pioneering technology combine old-fashioned functional alarm clocks with mobile phone wireless charging methods, which can be the most effective The use of the limited space of the bedside table reduces the pressure on the circuit caused by the device, and when you want to sleep, you can directly charge the phone by placing the phone on the wireless charging alarm clock, which is very convenient. For this, I have listed your five...

Best Bluetooth Alarm Clock 2021

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  In 2021, mobile phones have become an electronic product that people can’t live without. Do you feel anxious because you left your mobile phone, or even playing with your mobile phone when you go to the bathroom, then the mobile phone has become a part of your life. Mobile phones cause you to go to bed late. When you sleep, you set an alarm clock to wake you up in the morning and play with your phone for an additional hour. Do you want to get rid of this dilemma? Yunmei-wireless bluetooth alarm clock Nowadays, there is a  best Bluetooth alarm clock 2021 . It can also wake you up in the morning on time. Its sound level can be set, and it won’t wake you up too loudly. This alarm clock has a large screen, so You can see the time clearly from far away. In order to launch this alarm clock, we have done a variety of functional tests to ensure that this Bluetooth alarm clock can give users a good experience and allow users to enjoy the best performance of this alarm clock. To be ho...

Yunmei desktop wireless Bluetooth speaker alarm clock

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  If you insert a fever-level speaker configuration into your bedside alarm clock, what kind of experience will it be? Imagine that you are still asleep in the morning. At this time, the desktop   wireless Bluetooth speaker alarm clock   on the bedside suddenly rings. The sound of the bell is clean and delicate. The pure ringtone is intoxicating. In such an early morning wake-up service, there is indeed a difference. Kind of feeling. Compared with other desktop bluetooth speaker alarm clocks, Yunmei desktop wireless bluetooth speaker alarm clock is more unique, leaning towards the style of technology, designing a unique visual experience with a three-dimensional shape, full of texture, exquisite workmanship and good scratch resistance Features such as trace resistance and fingerprint resistance maintain the overall beauty of the speaker alarm clock. The more interesting thing is that Yunmei Bluetooth speaker alarm clock is equipped with a large LED screen in the middle of...

The current state of CD players

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  At present, it has to be said that   CD players   are already on the way out, not only in cars, but also in terms of storage media. CD disc is a kind of storage medium, in essence, there is no big difference between CD and flash memory and magnetic tape. The current situation of CD players is the same as the original cassettes. Just like cassette players disappeared from cars, CDs will be eliminated by the market sooner or later due to the low storage density and too large volume. Record companies can use write-protected U disks or even SD cards to replace CD distribution. In terms of portable music, portable CDs have been eliminated a long time ago. As a storage medium, optical disks began to decline after the emergence of large-capacity U disks and mobile hard disks. This can be seen on Sony's PSP. At present, optical drives are not considered standard on laptops. How many people have removed the optical drive and replaced the SSD. And Blu-ray has never been really po...