The first method is the most advanced technology and represents the direction of technological development. Its various technical indicators are also the highest. In particular, stability and reliability can be measured by telecommunication-level standards.
The second is a standard simulation system, but also a certain degree of practicality. Cable TV optical transmission has also been successful in this way, but in CATV optical transmission applications, video subcarrier modulation (using a professional AM-VSB modulator) and demodulation (through a TV tuner) functions Not included in the optical transceiver. The cable TV optical transceiver is only a radio frequency transmission platform, and the monitoring optical transceiver is mostly baseband to baseband transmission, which makes this technical solution have more shortcomings in transmission quality, stability, especially temperature drift and complex debugging.
The third kind should be said to be a transitional solution. It is achieved by occupying more fiber bandwidth resources. It is a choice when digital high-speed multiplexing technology does not reach a breakthrough. According to the statistics of optical fiber line faults, nearly 90% is related to optical passive devices, which is determined by the construction of optical passive devices and their manufacturing processes. The connection between complex optical devices inside the device greatly increases the loss of the optical link and leaves a lot of hidden troubles.
If you choose to know more about the technical solutions when you choose the optical transceiver, you can not only buy practical, understandable, but also greatly reduce the workload of the project opening and future maintenance.
At present, the gap between domestic video optical transceiver products and foreign products is getting smaller and smaller. However, manufacturers have different strengths in terms of technical strength, production scale, and product quality. There are not only regular military with an annual output value of tens of millions, but also small workshops with hundreds of thousands of annual output points. . Homogeneity on the low-end products is serious and competition is heating up. Undoubtedly, the lack of core technologies, complete product lines, and small-scale operations will soon be eliminated. In addition, the optical transceiver itself is a high-tech, precision product, and the use of optical transceivers is almost all-weather field environment. A mature optical transceiver, in addition to the circuit design, must also involve environmental temperature, power supply adaptability, shockproof, dustproof, moistureproof, and saline-alkali corrosion. These are by no means eager for instant benefits. Only by conducting field trips and strict product comparison tests with manufacturers, we can go on to save the truth.
The high-end digital video optical transceivers require higher technical content and higher requirements for manufacturers in terms of design level, staff quality, process flow, and quality control. In particular, high-speed optical fiber transmission platforms, high-speed digital multiplexing technologies, and precision manufacturing processes are not generally available to manufacturers. To give a small example: Now, almost all manufacturers have announced the use of surface mount (SMT) production technology, open the device to see, it seems that all surface mount components, it seems that there is no difference. Actually, otherwise, due to the difference in production scale among manufacturers, only manufacturers with large production capacity will be able to organize production according to the standard SMT production process and adopt a fully automated surface mount production line with welding quality assurance.
From the cost point of view, a large number of small-scale manufacturers are manufactured by hand-welding the patch components. Electrostatic damage to the chip during the soldering process has reached a level that cannot be ignored. Also, if there are only hidden defects in the soldering, soldering, and soldering processes of the RC components with only two ends, there are a large number of QFP-packaged precision, large-sized pins (up to 200) used in some digital optical transceivers. More than one) chips may be a disaster. Due to manual soldering, the stress on the chip in various directions is not equal, and the chip pins are easily damaged. This damage will not be immediate, but as time passes, deformation will occur gradually, resulting in fractures that will cause the equipment to fail after working for a period of time.
After all, optical transceivers are highly professional equipment. The irreplaceability in the project is far greater than other security products, such as cameras, DVRs, monitors, etc. The pre-sale, in-sale, and after-sales full-process technical support can be made available during the purchase process. In order to do more with less, it is recommended that a manufacturer with complete production lines, long product lines, complete varieties, complete functions, and strong technical force should be selected as a partner to build a new type of supplier, engineering, and user industrial chain with a win-win model.
1.cylindrical milling cutter
Used for processing flat surfaces on horizontal milling machines. Cutter teeth are distributed on the circumference of the milling cutter, and are divided into straight teeth and spiral teeth according to tooth shape. According to the number of teeth and coarse teeth and two kinds of fine teeth. The helical tooth rough tooth milling cutter has fewer teeth, high tooth strength and large chip space, which is suitable for rough machining. Fine-tooth milling cutters are suitable for finishing.
2. face milling cutter
Also known as disc milling cutter, used for vertical milling machine, end milling machine or gantry milling machine processing plane, end face and circumference have cutter teeth, also have coarse teeth and fine teeth. The structure has three kinds: integral type, insert type and transferable type.
3. End milling cutter
Used for processing grooves and step surface, knife teeth in the circumference and end face, can not work along the axial feed. When the end mill has end teeth through the center, axial feed can be provided.
4. Three-side edge milling cutter
Used for processing all kinds of grooves and steps, its two sides and circumference are provided with cutter teeth.
5. Angle milling cutter
For milling grooves at a certain Angle, there are two kinds of single Angle and double Angle milling cutters.
6.Saw Blade milling cutter
Used for machining deep grooves and cutting off workpieces, there are more cutter teeth on the circumference. In order to reduce the friction during milling, there are 15 '~1° auxiliary Angle on both sides of the cutter teeth. In addition, there are keyway milling cutters, dovetail slot milling cutters, T - shaped slot milling cutters and various forms of milling cutters.
End Mill,Roughing End Mill,Carbide Square Drill Bit,Coating Machine Tools
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