Pick the goggles don't attend to prevent mist

When swimming must choose a pair of goggles, good result can see underwater, secondly can protect the eyes. Lens to pick high-definition. When buying carefully the GuanChaJing clarity, light transmittance and prevent mist effect.

The short time swimming hemispherical lens face, can inspect sense clear realism over 95%, Long time swimming goggles with plane, prevent to produce myopia, but the mirror easy to cause the waves trace, poor perspective effect.

Many people buy the goggles pay attention to prevent mist sex, actually new goggles fog proof validity mostly for 3 months, three months after daub anti-fog coating need.

Glasses gasket suction wants moderate, not tight, the better. Currently on the market the goggles with rubber, silica gel etc give priority to, among them rubber is the most traditional material, it is hard, aging, cheap price, Silicone products to the skin and harmless, suitable for allergic crowd, anti-aging strong sex.

Inspection waterproof properties, firstly the mirror, put down by the goggles in eyes, and feel the gasket suction, meanwhile gently press lenses will inside lens discharge air, if the suction moderate, explain waterproof no problem.

Of course, waterproof performance will be different because of adding a little different, so when the choose and buy must do it myself. Gasket hardness wants moderate, too hard can cause a bone pain, too soft will lead to high intraocular pressure, will affect the use. 

1 day 4 a cup of black coffee absolutely crazy thin not only

The love drink coffee by more and more people, coffee charm of the taste of taking pains except it with spectacular aroma and refreshing xingnao role, coffee can also beauty! Together with a cup of coffee, recall boundless in this romantic moment, already full the luck to eat STH delicious, and beautiful face.

Product coffee thin body

The caffeine in coffee, have promote adipose decompose role, will adipose release in the blood, so drink coffee can also reduce weight. Generally 1 day 4 cups of milk without sugar and coffee can achieve ideal weight loss situation. But intestines and stomach indigestion, heartburn, easy insomnia had better not use this method.

If you don't habit of coffee acrid, can add the milk of a few, but do not add candy, because sugar can interfere with adipose decompose.

Hot coffee than iced coffee effective

Hot coffee can help you faster consumption quantity of heat inside body. Shallow the coffee that spends bake the most effective. Bake high temperature of coffee, although flavour is full-bodied, but coffeine content is less detrimental to reduce weight, and taste to compare weak American coffee is more advantageous lose weight.

Smell the coffee thin body

The aroma of coffee makes people mood stable and can improve sensory sensitivity, so work, drink a cup of coffee can improve work efficiency, also more can stimulate you to lose weight will.

Coffee exercising after slimming method

Because coffee drinking after 30 to 40 minutes in the blood of fatty acid concentration are high, at this moment with proper motion can be fatty acid into heat, effectively burning fat. For example a brisk walk for 10-15 minutes; Don't take the elevator and the stairs back office or home: can also situ small sport: like reverse extend upper body, tapping his feet, receive an abdomen, etc.

Coffee grounds massage slimming method

Use boiled coffee grounds massage can not only make skin smooth and firming, hairdressing effect. If use coffee slag mix coffee fluids in easy adipose corner of the lower abdomen, thighs, waist-buttock parts, such as blood, lymphatic flow along the direction toward the heart region move, can achieve decompose adipose result reducing weight, if bath when massage the effect will be better.

Coffee thin great consistence

Material: coffee powder right amount and massage oil amount method: coffee soybean meal and massage oil concocting, spiraling by cha thigh and want thin places.

Efficacy: coffee powder can promote skin blood circulation, avoid cellulite produce, make ham skin more tight.

Office coffee thin body best time

1 and after lunch 30 minutes to an hour, taste a bosom full-bodied, without sugar and coffee, conduce to partner after digestion and promote adipose combustion.

2, before coming off work another cup of coffee and cooperate on foot. 

Frequency band

Frequency band, is a communication related and sound streaks of words, communications aspects band means certain radio frequency range.

Communication frequency

concept

Band is certain frequency range.

For example, we use the radio, some can reap medium-wave, some can reap medium-wave, shortwave, and FM. People purchase the radio and total first to make sure it can receive several band, the band is equivalent to what we call tuner.

According to international radio rules, the existing radio communication was divided into aviation communication, sailing communication, land communications, satellite communication, radio, TV, radio navigation, positioning and remote measure, remote control, space exploration etc 50 kinds of different business, and for each business have stipulated certain frequencies.

Communication frequency division

Various communications system to use channel frequencies and a selective and rationality of the assignment problem, so reasonable use and try to save frequency resource, meet efficient and reliable transmission requirements.

For the cable channel, important is to choose a different transmission media and broadband media channel frequency reuse. General according to the channel business requirements, considering each they required of the foregoing cable channel (constant) the performance features of parameter, such as loss, delay and phase shift characteristics, and minimum and maximum cutoff frequency etc, to determine the tuner.

Undersea communication is suitable for extremely low frequency band, it has very good transmission performance, Any baseband signal transmission using baseband signal bandwidth for all the cutoff frequency low frequency band, analog voice low frequency transmission using only 300 ~ 3400Hz or quality sound (music) from 50Hz to 15kHz bandwidth.

Complex problem is, all kinds of wireless communication according to the space electromagnetic wave propagation characteristics, to choose and proper distribution working band. Itu-t R of spectrum allocation made specific rules, in various countries and various departments shall scientific and strict control frequency point use.

Electromagnetic wave by launching to receiving way can be divided into three kinds: one is to rely on through the ground; called "ground" 2 it is by space between two straight line dissemination called a "space; wave" Three is to rely on earth above the ionosphere reflection to the ground one hop or multiple hops strightline, called "TianBo".

Along the surface of the ground spread, because along the ground electromagnetic wave propagation induced current, jumping by ground this kind of good conductors attenuation, and the higher the frequency, the greater the integrating skin effect loss is bigger. Therefore for ground in mw (i.e. longwave and hundreds of KHZ to a few MHZ), such as broadcasting from 535kHz to 1605kHz frequency (each 10kHz a program) is an example.

Few MHZ to dozens of MHZ of short-wave (FFT) suitable for TianBo spread, sending the distance between the far outweigh the ground, can reach hundreds of kilometers to thousands of kilometers, depending on the antenna Angle size. Had mentioned above, the ionosphere to the reflection of the electromagnetic absorption, the attenuation, ionization concentration is bigger, and the loss caused by the ionosphere random changes in electromagnetic wave attenuation is undulating decline phenomena.

If a shorter wavelengths, i.e. higher frequency range, such as hundreds of megahertz to several JiHe (109Hz) above, the into microwave band. This frequency electromagnetic wave, the ionosphere, and no longer absorb rarely be reflected back to the surface. Such as satellite communications, electromagnetic wave can penetrate the ionosphere spread to a satellite. This kind of space wave propagation and light have analogue, not only straight line dissemination, and electromagnetic wave also have diffraction (diffraction) function, and can be bypassed some local obstacles. For example, microwave relay apanage pastry and between points straight line dissemination, besides should suffer ground environment (swamp, mountain, forest etc) certain influence outside, antenna, so too inconvenience erection relay (relay) section but four, 50 kilometers, usually called "over" communication.

Wireless communication all needs to transceiver antenna length and wavelength lambda matched antenna size for 1/4 · lambda, so use omni-directional antenna with the broadcasting radio antenna may not stable erect 100 meters. Using the GSM mobile phones 900MHz band antennas, can be short as a few centimeters long, for the mobile phone miniaturization portable bring great convenience.

All wireless communication are spread through free space, in order to reasonable use frequency, regions of communication and from mutual interference, ITU scientifically distribution of various communication system of applicable frequencies, each band frequencies and wavelength corresponding values and name, by the international telecommunication union (ITU wireless committee - R) promulgated, the countries and regions and cities are equipped with corresponding radio management committee for homeland and this district wireless fixed-frequency reasonable coordination. 

Internet access

Internet access through specific information acquisition and sharing of transmission channels, use the following transmission technology completing the user and IP wan high bandwidth and high speed of physical connection.

1, telephone dial-up (PSTN)

Common narrowband access method. That is, through telephone lines, the use of local operators access number, dial-up access to the Internet, rate does not exceed 56Kbps. Characteristic is easy to use, only effective telephone lines and cabin MODEM PC can be completed access.

Use in some low rate of network applications (such as web surfing, chatting, EMAIL query etc), mainly suitable for temporary access or no other broadband access sites use. Faults are rate is low, cannot achieve some high speed requirements of the network service, followed by higher cost (access fees by telephone TongXinFei and Internet use composition).

2, ISDN

Known as "the first tong". It USES digital transmission and digital switching technology, telephone, fax, data, image and so on many kinds of operation integrated in a unified digital network for transmission and processing. Users with a ISDN line, can be in Internet users at the same time telephone, fax, just like two telephone line the same. There are two basic rate interface ISDN 64kbps information channel and a signaling pathways, abbreviation 16kbps 2B + D, when people call dial the fashionable, it will automatically release a B channel to telephone. Mainly suitable for ordinary families users. Faults are rate is still low, cannot achieve some high rate of network services; request Secondly is charge also higher (access fees by telephone TongXinFei and Internet use composition).

3, xDSL access

Is mainly an ADSL/ADSL2 + the access method is given priority to, is currently using the most extensive copper access method. ADSL can be directly used to existing telephone lines, through ADSLMODEM after the digital information transmission. Theory can reach the 8Mbps rate of 1Mbps descending and ascending, transmission distance is up to 4 ~ 5 km. ADSL2 + rate can reach 1Mbps 24Mbps descending and ascending. In addition, the latest VDSL2 technology can be 100Mbps downlink each speed. Features are rate stability, bandwidth alone, without interfering with speech data etc. Applicable to family, personal and other users to most of the network applications, satisfy some broadband business including IPTV, VOD video (VOD), distance education, the videophone, multimedia retrieval, the LAN interconnected, Internet access, etc.

4, HFC (CABLEMODEM)

Is a kind of copper resources based on cable TV network access styles. Internet connection with special characteristics, allowing users to through the cable television network to realize high speed access to the Internet. Applicable to have cable television network in the family, individuals or small groups. Features are rate is higher, access convenient (through cable data transmission, do not need wiring), which can realize various video service, high-speed download, etc. Weakness is based on cable TV network architecture is to belong to the network resources sharing type, when the user surge, rate would decline and unstable, expansibility enough.

5, light broadband access

Via fiber-optic access to the village to the node or corridor, again by cable connected to each share point (usually less than 100 meters), provide certain areas of high-speed Internet access. Features are high rate and strong anti-jamming capability, applicable to family, individual or group enterprises of all types, may realize the all kinds of high rate of Internet application (video service, high-speed data transmission, remote sensing, etc.), defect is one-time wiring cost is higher.

6, passive optical network (PON)

PON (passive optical network) technology is a kind of point-to-multipoint fiber optic transmission and access technology, bureau end to client maximum distance for 20 km, total transmission capacity access system for each ascending and descending 155Mbps / 622M / 1Gbps, by all users to share, each user use of bandwidth can with 64kbps stepping division. Characteristic is access high rate and can realize all kinds of high rate of Internet application (video service, high-speed data transmission, remote sensing, etc.), defect is one-time invest more.

7, wireless network

Is a cable access extensions of the technology, use of radio frequency (RF) technology is empty sending and receiving data, reduce use wire connection, so the wireless network system can reach the purpose of construction of computer network system, and also can let equipment arrangements freely and move. In the public open places or enterprise internal, wireless networks will generally as existing cable network, a supplementary way with wireless card computer through wireless means convenient access to the Internet. 

Amusement regimen fishing fitness

Fishing as a kind of daily leisure sports, can not only raises the interest hobby, still can fitness, exercise. For people, kill two birds with one stone, why not?

1, heavy fall far-flung bait appropriate is small

Cast throw, bait regiment staff with lead fell by air and wind resistance. The resistance to the bait group size the line thickness is closely related to the bait regiment bigger its flight resistance is greater, placement is closer.

Cast rod want to throw far, you must use heavy fall small bait, with the help of a group heavy weight cast far, small bait can be molded into the wind resistance good oval, in order to reduce the influence of air and wind. But drive before the bait fish can be appropriately a few bigger, so quickly gathered fish bait.

2, add pendant in heavy favorable add hook

Cast rod fishing, some if in a natural body of water fishing, worry to use lead fall will hang bottom, have increased by using bait group, a method to bait and reduce hang, but avoid the lead not just as a role positioning, and make fish hooks functions.

Cast rod fishing is in DiaoZhe unwitting next biting, who all had no way of fish biting, only the first signal in fish hook after, DiaoZhe can get through. YuXun rod tip

Therefore, DiaoZhe not Yang rod before, make fish hook strength all from lead object, lead fell on a fishing in the group and the behavior of the fish hooks in a certain role of traction, if no lead object, would cause wiles puncture weakness, give fish caused more decoupling opportunity, so are fishing group had better not use fishing bait generation to fall, unless it is underwater method of 8,000 swarms of fishing bait fish with solid point of take and pharynx tooth of fish.

3, empty hook accept line speed evenly

Some if in left hook, rod fishing rod Yang group change, will accept line YuLun wave proclaim slower so that is quick, can make the line in not load conditions, ShiJinShiSong, causing line online slot showed irregular arrangement, at next cast hit not only easy fry line, but will also be disorderly line.

Therefore, a careful to every detail is necessary. Empty rod spooler make YuLun evenly maintain certain rotational speed, so even if line no load nor buried fry line hidden trouble.

4, empty hook up quickly to avoid hang bottom

Rod fishing rod with hand throw fish, but also in YuXun (movement) are under the condition of the staff, DiaoZhe in empty eagerly hope get have fish hook signal, excitedly Yang pole, when found empty rod, turning YuLun hand would be more wave slower.

When a gravitational big lead wire collecting power of movement, naked hook will fall bottom hook underwater 8,000 or tree obstacles such as silk and hang bottom, light is loss fishing group, heavy then pulled lines, himself to add needless trouble. Therefore, in DiaoZhe found hollowing rod or changing the bait, must pay attention to the empty hook fast on, avoid hang bottom.

5, first team ChaoWang wait for the fish into the copy

And the DiaoZhe a to the river, hurried mix bait fish hooks baited open, when a into the water, it ran to the other if place chat. The fish, embrace rod walk along while, prepare copy fish, just remember ChaoWang not installed, temporary hurry-scurry, very is passive.

Correctly method is put hooks baited into fishing points after should be timely assembly ChaoWang, lest the fish prior, sets a passive.  

Drink olive oil helps reduce weight

Speaking of olive oil, there are many people in it is not familiar with, and thinks of above all is the kind of waste bodybuilder wipe shining oil. It's actually a kind of edible oil, health care dramatically lower than other oil contains quantity of heat. Olive oil is not only rich in unsaturated fatty acid, still contain helps to prevent cardiovascular disease squalene, valley sterols and vitamin E.

Olive oil contains rich vitamin and oleic acid, including vitamin A can moisturize dry skin, prevent skin up scraps, Vitamin D can promote human metabolism, Vitamin E can stimulates the blood circulation unblocked, restrain skin further aging. Vitamin K is able to absorb subcutaneous redundant and adipose. It can not only help digestion, still can prevent constipation, so exercise every morning before, fasting 8ml ~ 16ml olive oil, drinking or append the milk, yoghurt, honey and fruit juice etc together, can cooperate with fitness, take to weight control effect.

Olive oil is rich in vitamin E and other antioxidants, can restrain the sun in active factor of the damage. Especially in other sports do mountaineering, run, before the sun but the sun is not very strong, can add a drop in skincare olive oil, avoid the skin by ultraviolet radiation damage, cause redness and swelling.

Suggestion: starting in exercise before applying heat towel first apply the lips, again with olive oil cover on lips, fingers lightly massage for a few minutes, hold to a few days will receive the good effect. Back on the sebaceous glands rarely, exercise and often expose outer, need often to replenish moisture and oily cent, otherwise, it is easy to crack cut. Carry-on prepare a bottle of olive oil, are washing their hands or feel dry wipe some to keep hands moist.

SMT(Surface Mounted Technology)

SMT（Surface Mounted Technology）electronics assembly industry is currently one of the most popular technology and technics.

SMT differ

High density assembly, electronic products small volume, light weight, patch of components of the bulk and weight only traditional cartridge elements 10 or so, generally USES SMT after, electronic product size decreased 40% ~ 60%, and the weight 60% ~ 80%. SMT

High reliability and vibration-proof ability. Solder defects low.

Frequency characteristic well. Reduce the electromagnetic and rf interference.

Easy to realize the automation and improve production efficiency. Reducing cost up to 30% ~ 50%. Save material, energy, equipment, manpower, time, etc.

Why should use SMT

Electronic products used in pursuit of miniaturization, already cannot narrow plugin components perforation.

Electronic product function more complete, adoption of integrated circuit (IC) has no punched components, especially large-scale, high integration IC, have to use the surface patch components.

Product PiLiangHua, automated production, the manufacturer with low cost but high yield, produce high quality products to meet customer demand and strengthen market competitiveness

Electronic components development, integrated circuit (IC) development, semiconductor materials to multiple applications.

Electronic technology revolution is imperative, chasing after the international trend.

SMT basic process elements

Printing (or dispensing) - - - - > > mounted (cured) - - - - > > reflow soldering clean -- -- > > detection repair

printing

Its function is to solder paste or patch glue to its of the PCB soldering plate, and preparing for the components of welding. Equipment used for printing presses SMT processing workshop

(solder paste printer), located in the SMT production line of the front-end.

dispensing

For now is used mostly double-sided PCB patch, to prevent second down into the components for when solder paste again melting and peels, therefore, in input face plus deck glue machine, it is will glue drops to the PCB's fixed position, its main effect is components fixed to a PCB. Equipment used for dispensing machines, located at the forefront of SMT production line or testing equipment of behind. Sometimes due to the customer request output surface also need some glue, but now many small factories all need not dispensing machines, if input surface components bigger when employing worksite glue.

Pasted on

Its function is to surface assembly components installed to the PCB's fixed accurate position. Equipment used for placement machine, located in SMT production line of printing machines behind.

curing

Its function is to patch glue melting, thus making the surface assembly components and PCB firm bonding together. Equipment used for curing furnace, located in SMT production placement machine of behind.

Reflow soldering

Its effect is solder paste is melting, make surface assembly components and PCB firm bonding together. Equipment used for reflow oven, located in SMT production placement machine of behind.

cleaning

Its function is to assemble the good PCB above harmful to human body welding residues such as flux, etc to eliminate. Equipment used for cleaning machine, position can not fixed, can online, also don't online.

detection

Its function is to assembly good PCB assembly welding quality and quality detection. Equipment used have a magnifying glass, microscope, online tester (ICT), flying probe tester, automatic optical inspection (AOI), X RAY detection system, function - tester etc. According to the test needs, position can be furnished with production line appropriate place.

repair

Its function is to detect malfunction PCB board undertakes rework. Tools for iron and repair workstation, etc. Configuration in production line in any position.

SMT common knowledge introduction

1. Generally speaking, SMT workshop specified temperature for 25 + 3 ℃.

2 the printing, prepares the material and tools required for solder paste, steel, scraper, wipe paper, air-laid paper, cleaning agents, mixing sword.

3. Usually used for solder paste alloy ingredients, and Sn/Pb alloy alloy ratio for 63/37.

4 the solder paste in main ingredients into two most tin powder and flux.

5. Flux in the main function is to remove weld melting tin oxide, destroy the surface tension, prevent oxidation again.

6. The solder paste in tin powder particles and Flux (Flux) volume ratio of about 1:1, the weight ratio of about now.

7. The solder paste and use principle is advanced in first out.

8. The solder paste in kaifeng when using, shall undergo two important process back to temperature, stirring.

9. Steel common methods of producing for: etching, laser, electroforming.

10. SMT's full name is mounting Surface mount technology (or), Chinese meaning for the Surface adhesion (or mounted) technology.

11. The ESD is the full name of Electro - static fiberglass, Chinese meaning for electrostatic discharge.

12. Make SMT equipment applications, program, including five most, the five parts for PCB data, Mark data, Feeder data, Nozzle data, 'ts data.

13. Lead-free solder Sn/Ag/Cu 96.5/3.0/0.5 melting point for 217C.

14. Parts of the relative humidity controlled for drying oven < 10%.

15. Common passive components (PassiveDevices) are: resistor, capacitor, some sense (or diodes); etc. Active components (ActiveDevices) are: transistors, IC, etc.

16. Common SMT steel plate made of stainless steel.

17. Common SMT steel plate thickness.15 mm (or 0.12 mm).

18. Static charge produce kinds of friction, separation, induction, electrostatic conduction; etc. Static charge on the influence of the electronics industry for: ESD failure, electrostatic pollution; Static removing the three principles for electrostatic neutralization, grounding, shielding.

19. The imperial size long x width 0603 = 0.06 a * 0.03 a long x width size, metric 3216 = 320 mm * 1.6 mm.

20. Exclusion ERB - 05604 - J81 8 yards "4" expressed as four loops, resistance to 56 ohms. Capacitance ECA - 0105Y - M31 let value of C = 106PF = 1NF = 1X10 - due.

21. ECN Chinese all known as: engineering change notification, SWR Chinese all known as: special needs work, must by relevant departments counter-sign, document centers distributed reply.

22. The specific content of 5S to collating, rectify, cleaning, cleaning, literacy.

23. PCB vacuum packing is the purpose of dust-proof and moistureproof.

24. The quality policy for: total quality management, implement system, provide customer needs quality, Full participation, timely treatment, to achieve zero defect targets.

25. Quality three-no policy is: don't accept bad product, not manufacture defective product, not outflow non-conforming.

26. The QC seven gimmick in 4M1H respectively in the fishbone check reason means (English) : man, machines, materials, methods and environment.

27. The solder paste ingredients include: metal powder, soluble jinan, flux, resistance to vertical flow agent, surfactant, By weight points, metal powder of 85-92%, by volume points metal powder 50%, Including metal powder ingredient for tin and lead, proportion to 63/37, melting point for 183 ℃.

28. The solder paste must be used with from the refrigerator to temperature, the purpose is: let refrigeration solder paste temperature reply at normal temperature, eli printing. If you don't return temperature is in PCBA into Reflow easily after the adverse for tin beads.

29. Machine of document and supply mode are: prepare mode, priority exchange model, exchange model and speed connect mode.

30. SMT PCB localization way: vacuum positioning, mechanical hole positioning, bilateral clip positioning and plate edge localization.

31. Printing (symbol) 272 resistance, resistance is 2700 Ω, resistance is 4.8 M Ω resistance of symbols (printing) for 485.

32. BGA ontology of silk contains manufacturer, the manufacturer materials issue, specification and Datecode / (guernsey aubject) and other information.

33 the 208pinQFP pitch for 0.5 mm.

34 QC seven gimmick, the fishbone diagram emphasize find causality,

35. CPK refers to: at present practical situation of process capability,

36. Flux in constant temperature zone to begin volatile chemical cleaning action;

37. The ideal cooling zone curve and reflux area curve mirror relations;

38. Sn62Pb36Ag2 of solder paste main trial in ceramic plate;

39. Start with rosin primarily flux can be divided into four kinds: R, RA, RSA, RMA;

40. RSS curve for heating furnace-rough thermostatic - backflow - cooling curve,

41. We are currently using the PCB material for FR - 4,

42. No more than the PCB warping specifications diagonal 0.7%,

43. The STENCIL production laser cutting is ok again dhi method,

44. The present computer motherboard is used for 0.76 mm BGA ball diameter,

45. The ABS system for absolutely coordinate;

46. Ceramics chip capacitor ECA - 0105Y - K31 error more or less 10%,

47. Currently used computer PCB, its material for: glass fiber board;

48. SMT parts packaging its volume belt type dish for 13 inch in diameter, 7 inches,

49. SMT general steel myriapod than PCB PAD small 4um can prevent tin ball adverse phenomenon;

50. According to "PCBA inspection norms. When ErMianJiao > 90 degrees said solder paste and wave soldering body without adhesion,

51 after unpacking j IC card is greater than the humidity in the humidity 30% of cases said IC damp and moisture absorption,

52. Solder paste ingredients in tin powder and flux weight ratio and the volume ratio of right is 90% : 10%, 50% : 50%;

53. Early of the surface of sticky outfit technology originated in the mid 1960s the military and aerospace electronics field, 54. The current SMT most frequently used solder paste of Sn and Pb content of each 63Sn 37Pb; for:

55. Common bandwidth for 8mm tape materials plate for feeding spacing 4mm;

56. In the early 1970s, the industry have recently a SMD, for "sealed but no feet chip carrier", often in HCC Jane generation.

57. The symbol for the components of the resistance should be 272 2.7 K ohms,

58. 100NF component tolerance of the value and the same; 0.10 uf

59. 63Sn 37Pb the eutectic point for 183 ℃;

60. SMT usage's biggest electronics parts material is ceramics;

61. Back to welding stove temperature curve its curve 215C most suitable; the highest temperature

62. Tin stove when examination, tin stove temperature 245 ℃ more appropriate,

63. Plate opening roller type squares, triangles, round, astral form; this lei,

64. SMT section exclusion or without direction,

65. At present on market sale of solder paste, actual only 4 hours sticky time,

66. The SMT equipment use commonly 5KG/cm2 rated pressure for,

67. SMT parts maintenance tools are: soldering iron, hot air BaQu device, both absorb gun, tweezers,

68. The QC is divided into: IQC, IPQC and OQC FQC;.

69. High speed placement machine can be pasted on the resistor, capacitor, IC, transistors,

70. Electrostatic features: small current, influenced by humidity,

71. Positive, negative SMT PTH tin stove used what soldered turbulence double-wave welding;

72. SMT common inspection method: visual inspection, X-ray and machine visual inspection

73. Ferrochrome repair parts to the conduction convection heat transfer mode,

74. Currently BGA material its tin ball into Pb10; the main Sn90

75. The plate making method laser cutting and electroforming method, chemical etching,

76. The temperature according to eave welding stove temperature measurement him mad: using the applicable temperature,

77. Eave welding stove SMT semi-finished products in the export when its condition is fixed in welding parts on the PCB,

78. Modern quality management and development of the TQA - TQM; TQC -

79. ICT test is needle bed testing;

80. ICT test can measure electronic parts adopt static test,

81. Soldering characteristic is melting point than other metal low, physics performance meet the welding conditions, low temperature fluidity than other metal good;

82. Eave welding stove part replacement process conditions change to remeasure measure curve,

83. Siemens 80F/S belong to a electronic control transmission;

84. Solder paste thickness gauge is using Laser light measurement: the solder paste degrees, solder paste thickness and width of solder paste printed,

85. SMT parts feeding a vibrating type for distributor, discotic for distributor, roll belt for feeder,

86. SMT equipment use which institutions: CAM mechanism, side bar institutions, screw institutions, sliding institution,

87. Visual inspection section is required if cannot confirm in accordance with any assignment BOM, manufacturer confirmed, sample plate;

88. If parts for 12w8P packing method, the counter Pinth size must be adjusted each into 8mm;

89. Eave welder sort: hot air type eave welding stove, nitrogen eave welding stove, laser eave welding stove, infrared eave welding stove.

90. SMT parts can be used for sample test method: streamline type production, fingerprints machine mounted, handprint hand mounted,

91. Common MARK shape has: round, "10" glyph, square, triangle, the diamond, million glyph,

92. Reflow Profile Settings for SMT section undeserved, may cause parts micro cracked is preheating zone, cooling zone;

93. SMT period ends heated parts easy create: empty uneven welding, and deviation of, tombstones,

94. High speed machine and domestic machine should as far as possible equilibrium; a pa

95. The quality is the intendment of do it right the first time,

96. Placement machine should first post small parts, after stick big parts;

97. BIOS is a basic Input/Output System, the full English Base Input/Output for: views,

98. SMT parts according to parts feet can be divided into two kinds of LEADLESS and organization;

99. Common automatic placement machine there are three basic types, succeeded type placed type, type and large weave-machines.continuative placed transfer type placed machine,

100. The SMT process without LOADER can also production.

101. SMT process was delivering plate system - solder paste printer - high speed machine - domestic machine - separated flow welding - unloader,

102. The temperature sensitive parts kaifeng, humidity card circle show color to blue, parts can be used;

103. The specification of 20mm not strip width,

104. Cheng for printing adverse short-circuited reasons: a. solder paste metallic content enough, causing collapse b. steel openings caused by excessive, the tin quantity overmuch cristiano steel quality was not good, bad, change under the tin on the back d.S laser cutting template tencil solder paste, lower residual have squeegee pressure, using appropriate VACCUM and SOLVENT

105. General back welding stove Profile of the main engineering districts purpose: a. preheating zone; Engineering objective: the solder paste zhongrong agent volatile. B. mean temperature area, Engineering objective: flux activation, remove oxides, Evaporation excess water. C. back welding area, Engineering objective: solder melting. D. cooling zone; Engineering objective: alloy solder formation, feet and pad connect parts for an organic whole;

106. SMT process, tin bead the main causes of the: PCB design, improper PAD plate opening of poor design, buy thing depth or buy thing too much stress, Profile curve rose slope too large, solder paste viscosity collapsed, too low.