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Anonymous users2024-01-24Weak electricity is relative to strong electricity and weak electricity Conceptually speaking, it is generally easy to distinguish, and the main difference is the difference in use. Strong electricity is used as a power energy source, and weak electricity is used for information transmission. Specifically, they are roughly as follows:
(1) The frequency of strong electricity is generally 50Hz (Hz), which is called "power frequency", which means the frequency of industrial electricity: the frequency of weak electricity is often high frequency or ultra-high frequency, measured in KHz (kilohertz) and MHz (megahertz). (2) Different transmission methods Strong current is transmitted by transmission lines, and weak current transmission is divided into wired and wireless.
Radios transmit electromagnetic waves. (3) The power, voltage and current are different The strong current power is measured in KW (kilowatts), MW (megawatts), the voltage is measured in V (volts) and KV (kilovolts), and the current is measured in A (amperes) and kA (kiloamperes); The weak current power is measured in W (watts) and mW (milliwatts), the voltage is measured in V (volts) and mV (millivolts), and the current is measured in mA (milliamperes) and uA (microamps), so its circuits can be composed of printed circuits or integrated circuits. Of course, there are also high-frequency (hundreds of KHz) and medium-frequency devices in strong electricity, but the voltage is higher and the current is also larger.
For example, flashlights and electric shavers are still strong electricity even though the voltage is very low, and the power and current are very small. Due to the development of modern technology, weak current has penetrated into the field of strong electricity, such as power electronic devices, wireless remote control, etc., but these can only be counted as the weak current control part of strong electricity, which is still different from the controlled strong current.
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Anonymous users2024-01-23It should be connected to 220V, where do you find a 7V power supply, yes, boldly install it,
Gold is positive, silver is negative, and this side is connected to the amplifier output.
Kaiboer's high-definition machine,Cheap but with big limitations,Android price is high and the limitations are larger than the computer,Or install a computer,It doesn't have to be an apu,It is recommended that you consider Intel's new CPU in September - g530 is more than cost-effective,It's more than enough to see HD,The host price can be controlled around 1000,The integrated APU is not as good as G530。 G530 is the king of cost performance in low-end CPU, because it has just become famous, it must be famous in the future, beat AMD250 in the actual test, and Intel's Pentium E5800 is a tie, and the energy consumption is standby 25W! It is the best choice for HTPC!
If you think like this, only those who are worthy of saying will be talked about and envied. If you are an unknown person, you don't have this opportunity to be said.
Solid wood finger joints will cover the wood grain for the sake of beauty when making paint, so if you want to preserve the wood grain, choose the whole board.
The furniture made by yourself will be a little better than buying in terms of environmental protection, but the style and workmanship are not as good as the products on the assembly line, and the current manual cost is very high, so if there is ready-made wood at home, or because the structure of the room needs some special size furniture, you can find carpentry to do, and it is better to buy spot in other cases, as long as you pay attention to the environmental protection indicators of furniture when buying.