Published: 2004-07-09 11:17:04 original author: ele-diy |
      I made an active computer power amplifier, and its effect is very good. These circuits are worth a try for beginners and those who like to do it by themselves. The printed circuit board of this circuit is optimized by design and has operability. As long as the wiring is in this style, a satisfactory circuit can be designed. Of course, if you add more ground wires, the effect will be better. The whole circuit is shown in the figure below.       The printed circuit board of this circuit adopts single-panel wiring. The circuit is optimized and drawn by protel software, and after many actual production adjustments, it focuses on solving the noise of the circuit itself. The input and output lines of the circuit enter and exit from the two sides of the circuit, respectively Careful consideration, especially the wiring design, fully considered the characteristics of the components and improved the input and output quality of the circuit. Front view of PCB On FIG. 1, FIG. 2 is a view of a circuit board traces, note FIG two opposite faces, their relationship to be noted that the actual production. FIG front stage circuit J1 is the two-channel input terminals, R8 and R10 are an input resistor 20k, R1 and R2, C1 and C2 for improving tone, R7, W1, C8, IC1 combined into a feedback tone adjustment circuit, C10 Used for super audio filtering, sometimes it can be used without installation. W1 takes 5k ~ 10k for tone adjustment. Circuit IC1 is used for pre-amplification. ③ pin is positive phase input, ② pin is negative phase input, ①pin is output, dual 12V ~ 15V power supply, R * can be added to the input to improve the no-load noise, and the value can be 500 ~ 5k . After using FIG TDA2030A circuit stage for a power amplifier with dual power supply 12V ~ 15V, 10W provides more power, wherein W2 is a volume       According to the schematic diagram, the list of components from left to right is shown in Table 1 , where the symmetrical components of the left and right channels are placed in the same square. The picture on the upper left is the picture of the component surface of the finished board. All components except the capacitors should use non-polar capacitors as far as possible, and other components can generally be used as long as the voltage meets the requirements. |
Article source: 2004 7th issue of electronic production magazine Editor in charge: ele-diy |
The regulator,The so-called mini projector is also called pico projector, TRT-Lcos Portable Projector. Mainly through the 3M LCOS RGB three-color projector and 720P film decoding technology, the traditional huge projector is refined, portable, miniaturized, entertaining and practical, making the projection technology closer to life and entertainment.
Usually the projector has certain regulations on 2 aspects:
a). Size: Usually the size is the size of a mobile phone.
b). Battery life: It is required to have at least 1-2 hours or more of battery life when it is not connected to power.
In addition, its general weight will not exceed 0.2Kg, and some do not even need fan cooling or ultra-small silent fan cooling. It can be carried with you (it can be put into your pocket), and the screen can be projected to 40-50 inches or more.
Advantage:
1. Completely replace the MP5 player, video, listening to songs, playing games, e-books, picture browsing, etc. MP5 video is affected by physical performance, the screen can not be bigger, and the screen of this thing is at least 20 inches.
2. Instead of the TV function, the machine can have a built-in CMMB function, or it can be directly connected to the set-top box to play the TV, and it can be used as a 21-inch TV during the day.
Look, it can be used as a 60-100-inch TV at night to achieve the effect of home theater; it is convenient to move and break through the traditional film and television space. Even if you are on the mountain, you can also share today's TV series, movies, and MTV with your lover.
3. Business office: instead of large projectors, it is used for company meetings; the price of large projectors is 4,000 to 14,000, and the lamp life is more than 1,000 hours, which is not convenient to carry. 30,000 hours, no need to change the bulb for 3 years, easy to carry, the salesman only needs to bring a micro projector to demonstrate the new product, which can achieve the demonstration effect.
4. Teaching: training meetings, classroom teaching; traditional projectors are not easy to carry. In school classrooms, due to the naughty students, projectors are not safe to place in the classroom and are easily damaged by students. The portability of micro projectors makes up for the teaching vacancies. In the future, teachers only need to store the materials in the projector and show them to students for teaching, saving the trouble of textbooks and handwriting with pens and chalks.
In addition, the micro-projection has no radiation, which can fully protect pregnant women and people with myopia. Its low power consumption function is 1/1,000,000 of the power consumption of color TVs. One day of electricity has completely impacted the indicators of safety, environmental protection, health, etc., and has made amazing contributions to future social development, standing at the peak of the green world as a leader.
best mini projectors under £100,mini projector pvo portable projector,mini projector portable,mini projector amazon,mini projectors for movies
Shenzhen Happybate Trading Co.,LTD , https://www.happybateprojector.com