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| Wednesday, 9-May-2012 00:46 |
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DC/DC power modules in the medical application of sensor circuit
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Currently, as modern medical instruments of constantly development, especially directly and human phase connection of electronic instrument, apart from on instrument itself performance of requirements increasingly high zhiwai, on human security area of considered also increasingly's award-winning concern, such as life guardianship instrument, and maternal and child guardianship instrument, and baby insulation instrument and so on Panasonic Lumix DMC-FZ28 Battery Charger some and human close contact of instrument, that is patients in using instrument Shi cannot because using of instrument and on human caused has shock or other area of dangerous.
Second, the application of ECG signal detection circuit
With normal ECG detection circuits, for example to introduce a simple, shown in Figure 1:
Figure 1: the normal type electrocardiogram detection circuit.
Figure 1 is a practical circuit of INA115 electrocardiogram detection circuit. Positive and negative input of the amplifier by ECG sensor respectively received the body's left arm (LA) and the right arm (RA), and amplifier to which the n-driven network of R1~R4 and resistance of human right leg (RL), constitutes a "floating". Owing to the weak bio signals, coupled with the polarization potential, so the magnification level is not too high, generally take between 10~100, and only as a preamplifier used, in order to test security, after the level should no longer be isolated isolation amplifier, and the level of the power supply voltage isolated power supply module provides the best should be to achieve power and signal totally isolated. As shown in Figure 2,
Figure 2: isolation-ECG detection preamplifier circuit.
Above circuit is made up of Chinese companies such as T6235D and INA115, isolated before detection of ECG amplifier circuit, the circuit due to its high input impedance, low leakage current, high measuring accuracy and meet the security indicators, such as the human body can fully meet the requirements of medical devices use standard. The circuit as a preamplifier circuit, direct contact with the human body, and picks up after the ECG to zoom through the INA115, after the last transfer from ISO122 isolation to amplification circuit to achieve isolation amplifier of signal and output and the power of the human body.
Amplifier power application have sufficient security of Creepage distance, high isolation voltage characteristics and isolation of extremely low capacitance values, the system security can be better protected, Jin Shengyang 6000VDC here recommended isolation g series (constant pressure input, isolated 6000VDC of positive and negative voltage output) or h series (constant pressure input, isolated 6000VDC single channel voltage output), The series due to its very high isolation voltage characteristic (6000VDC) and JVC GR-D90U Battery Charger it has a very low capacitance values of isolation (≤ 10pF) is widely used in the medical device industry. G1515S-1W INA115 contact with the human body's ground wire and disconnect input power cables really, completely isolating effect, that is, full of power and signal isolation.
Selection of three, isolated DC/DC power modules:
Figure 2: isolation-ECG detection preamplifier circuit.
Note: the above work programme is based on the isolation amplifier voltage ± 15V made under the conditions of, such as the operating voltages of ± 5V ± 12 and other voltage as long as you can select the output voltage of the product.
Four, the use of DC/DC power modules in the process should be aware of the following issues:
External capacitor C2, C3 DC/DC power modules with low internal resistance of tantalum capacitor, capacitance values recommended 0.47uF should avoid tolerance value is too large, to prevent the starting moment due to capacitance too large too corrupted streams modules;
For guarantee module long-term work of reliability should makes to module work in 10% rated power above, to prevent module due to unloaded or light contains led to output voltage does not stability and effect circuit work, if load power does smaller, can mining and external fake load of way in output end of +Vo and 0V and the-Vo and 0V Zhijian and Shang a 10% rated power of fake load (resistance), to improve products of reliability.
Due to DC/DC power module is used switch oscillation circuit to implementation of, its itself also will produced total die, and difference die noise of interference, for on sheath wave noise requirements high of occasions can in DC/DC power module of output end external no source LC filter network or RC (loss larger), to further reduced power sheath wave noise, but to note l itself resonance frequency to far than module of switch frequency, allows by of current value best in module entered current of twice times above, internal resistance to small, to reduced DC loss. May refer to the following diagram:
Above is to introduce a DC/DC module power supply in the field of medical electronics, especially sensor detection circuit characteristics, application and selection of the matters needing attention in DC/DC module Nikon EN-EL11 Battery power supply, DC/DC power modules lot currently on the market, but because of medical electronics belong to special industry, to its power requirements are very high, to guarantee the safety of human and equipment performance, select DC/DC module power supply is particularly important.
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| Friday, 13-Apr-2012 00:41 |
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LDO improved degree of matching white-light LED
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White LED light and with the use of simple, low-cost advantage compared to fluorescent lamps, can offer a true white light in comparison with incandescent lamps, and therefore its usage in recent years showed a steady increase in the trend, handheld Nikon Coolpix P300 Battery Charger products are widely used as Flash, video in backlight. Of course, in practice for white-light LED there are some technical issues to be resolved.
Use white light LED the most obvious problem is the product of poor match, follow the typical white-LED specifications, minimum value of the currents as 20mA to voltage is 3.0V, a typical value is 3.5V, the maximum value is 4.0V. Clearly, the voltage source is not a reasonable solution. Of course, use the same current drive each LED can be uniform brightness, but the cost is very high. In many applications simply use a fixed-bias voltage and flow resistance of the town Drive LED, as shown in Figure 1.
Figure 1 design of circuits can often be very good brightness match. But for the mass production of the user, of the same batch of products with a fairly consistent characteristics, but poor consistency between batches. This need to test each batch of new LED, to configure ballast resistance. If there are multiple suppliers LED the problem will become more serious. For more description above problem, selection three a manufacturers of LED (respectively with-a, and b, and c said) in accordance with Figure 1 by shows circuit for has following test, label for-a of LED selected since a level white light LED suppliers, label for b of LED selected since II level white light LED suppliers, label for c of LED is from electronic supporting market purchase of cheap LED. Test results are shown in table 1.
You can see from table 1, LED to the same manufacturer matches better, especially from the supply of the larger manufacturers of products (a, b, two LED), three vendors average LED current of mean square error is 0.54. White-light LED from different vendors in the same bias voltage, the same town of resistance current difference is large, mean square error for 3.27mA. Individually control each LED current, or at least for one can improve the current regulation of different manufacturers of LED or LED by the same vendor in different batch consistency, but this requires very expensive chips. Cost of demanding products, can take advantage of low-dropout linear regulators (LDO) improve the consistency of LED, no need to select the resistance of different ballast resistor, circuit as shown in Figure 2. LDO voltage regulator-in steady flow mode, as a forward voltage of the LED's change automatically adjusts the bias voltage.
Checking circuit of Figure 2, a, b, and c of these LED in accordance with Figure 2 electrical connection testing, test the results in table 2. 2 can be calculated from the table, same manufacturer of LED current consistency fell slightly (Figure 2 results for Panasonic Lumix DMC-FP5 Battery Charger 0.77mA, Figure 1 results of 0.54mA), but different manufacturers of LED current consistency has been greatly improved, lowering the mean square error from 3.27mA to 0.96mA.
Circuit of Figure 2 Select pins with external voltage regulator LDO, such as MAX8863, the feedback threshold for 1.25V (the Vset). Selection of LDO SOT23 package can improve system performance, because the majority of LDO SOT23 package with the relevant control broken, thus eliminating the control LED in the circuit of Figure 1-pass/broken n-Channel MOSFET. In addition, LDO has a wide input voltage range, when you and other circuits share the same +5V power supply can provide high power supply rejection ratio (PSRR).
Amendment to the circuit of Figure 2 Figure 3 circuits, each LED current of 15mA, backlight requirements for portable products.JVC BN-VM200U Battery Charger MAX8863 can drive 8 LED, each LED current of 15mA. When the LED forward voltage is low, or ballast resistor currents lower than 15mA, allowed input voltage is low.
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| Friday, 9-Mar-2012 01:04 |
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Greepoint chorus the main melody green and energy-saving
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As the United States national environmental protection agency and Department of energy to the consumer promotion of high quality and high efficiency energy-saving products certification program, United States energy star projects, in 2005 alone to consumers saving a total of more than US $ 12 billion of electricity throughout the country, saving the equivalent of 1.5 or more than 50 new TGP power station. But in China, only some cities start standby energy consumption plan and achieved a modicum of success. According to the survey of successful anasonic DMW-BCJ13 Battery Charger certification center, urban households in China average standby power consumption is equivalent to 24 hours a day using a 15 watts to 30 watts of "eternal fire", quietly eating into electricity and a valuable source of energy. To TV as a case study in China, Chinese TV limited values of energy efficiency and energy-saving evaluation of value of the current index for standby power 3 watt, on March 1, 2009 goal is 1 Watt. If China are up to 3 Watts of standby energy consumption of all color TV standard, may save 6 billion yuan, or 12 billion by 2011.
Standby power consumption is the main source of electronic equipment and household appliances energy waste, refers the user to turn off electrical devices, electrical equipment on standby still consume electricity. As energy-saving awareness around the world enjoy popular support, standby power consumption and resulting environmental problems caused by rapid growth of increasingly widespread concern and has become a hot topic of concern to the international community. "1-Watt plan" was in 2000 by the International Energy Agency (IEA) to its member countries launched by producers and distributors of electrical products and energy saving initiatives, implementation of targets by 2010 1 Watt standby power. At present, the scheme has been the European Union, the United States responded positively.
"On semiconductor is committed to improving the energy efficiency of power supply, we provide high energy efficiency, low standby solution has many innovative techniques such as jump cycle, shut down, power factor correction, frequency counter-go. Not only do we have the price, less than 1 watt of standby power solutions also provide power system-level solutions, helping customers meet consumer demand for light, energy saving and multifunctional products. "On semiconductor Asia Pacific Vice President of marketing, maimanquan said. The company through innovative Greepoint series chorus the main theme of green and energy-saving programme for the industry.
160W CRT TVs power supply reference design
Although CRT TVs in the past two years has been covered by LCD and PDP TVs like a ton of bricks, but according to the figures, 70%, 2006, global TV market share was CRT occupies, and in 2010 will have 100 million television market. On semiconductor GreenPoint for CRT TVs power supply reference design can provide standby power consumption below 1W. The 160 w energy-efficient reference design to solve the power of all the function blocks, and comply with the international code for low standby power consumption. The reference design as shown in Figure 1.
Figure 1 GreenPoint for CRT TVs power supply reference design
In Figure 1, the leading device is reinforced by pulse width modulation (PWM) current mode controller NCP1337. The controller combines the real current-mode modulator and detector for demagnetization, ensures that any load/full line on the line/critical conduction mode. The frequency is limited to 130kHz, fully consistent with the conductive EMI emission standards (the minimum limit of 150kHz).
The controllers as long as the power requirements below the preset level, they work by monitoring the feedback pin, enter the ripple pattern. 160W CRT TV standby energy consumption is reduced to below 1 w, and adapter no-load energy consumption to meet the most stringent requirements. Restart the internal soft start to soften, frequencies cannot be less than 25kHz, so there is no noise.
NCP1337 efficient internal consolidation of the protection circuit, overcurrent case, attempts to restart, and close the output pulses into safe burst mode. As soon as the fault disappears, automatic recovery device, power is restored. At the same time, the controller also included is called the input under voltage protection (Brown-out protection) of the total voltage detection function. This is an adjustable overload compensation, quasi-resonant power supply can handle provides maximum power input voltage change impact on, and Vcc on the overvoltage protection. In addition, within 4 milliseconds (MS) soft start eliminates the traditional start of stress. Not only applies to CRT televisions, also suitable for LCD TV, PDP TV, notebook computer, offline battery charger AC-DC adapter, DVD players and set-top boxes and other consumer electronic products, as well as any power for high energy efficiency and low EMI.
"We develop, build and fully test the CRT TVs power supply reference design, provided additional assistance on semiconductor industry-leading energy efficiency of consumer electronics products. Close collaboration with our customers around the world to jointly develop the design, as well as all of our GreenPoint power solutions, to Nikon Coolpix P300 Battery Charger ensure access to effective solutions to meet power needs now and in the future. On semiconductor will continue to provide ' green ' energy-saving solutions, reduce the burden on customers in design emphasis increasingly efficient power supply. "VP of on semiconductor power switch Andy Williams said.
90W notebook power adapter reference design
On semiconductor GreenPoint fourth paragraph reference design, dedicated to 90W notebook power adapter. The reference design uses a single method, eliminates the burden of two-stage power handling, providing real energy efficiency. Therefore, while all the power supply modules to solve power adapter, obtain low standby power consumption and in compliance with applicable United States California Energy Commission (CEC), energy star, as well as the European Code of Conduct requirements. "The extension reference design on semiconductor in advanced power management semiconductors leading to a high performance notebook power adapter. This laptop adapter fully tested solutions on semiconductor is used in the process of developing in high efficiency power supply design professional and technical, original equipment manufacturer (OEM) is used to provide energy-efficient products to the market. "Andy Williams said.
The new GreenPoint? adapter reference design structure of the circuit shown in Figure 2, energy efficiency as high as 90%. Through the use of patented Dan Duantuo of topology, need to be far less than the number of elements of traditional two-stage programme, at the same time, the reference design is also fully compatible with OEM on surface temperature and 100 μA leakage current requirements.
NCP1651 is the reference design-led devices. The device is designed for universal input range in 50/60Hz power system (85Vac-265Vac) of active power factor correction controllers. Design patent the device using multiplier, compared with traditional analog multiplier, more accurate. Isolated AC/DC converters provide high output voltage requirements of low cost, low component count solutions, and can easily meet the 50W-250W IEC1000-3-2 harmonic range Converter requirements.
To reduce the output ripple and harmonic currents remain within the class d requirements of IEC1000-3-2, the reference design uses a ripple-ERS, developed by double-loop/power factor optimization technology. "Patented design, we are able to overcome the disadvantages of Dan Duantuo topology, and directly address the notebook power adapter-specific requirements. We work with on semiconductor, close co-operation with key customers, focus on key performance parameters. The result, we succeeded in developing a low-cost single-stage solutions, not only can provide the required performance and design complexity far more complex and two of the more common scenarios. "ERS President Abdul Sher-Jan said.
Figure 2 90W notebook power adapter reference design
60W power adapter reference design
On semiconductor GreenPoint fifth paragraph reference design, is used for LCD TVs and monitors, notebook computers and other consumer electronic products, 60W power adapter. The new reference design to satisfy not only the standby and operating mode energy efficiency standards for design challenge onerous, and cost-effective solutions. "Our new 60W adapter reference design combined with a 90W GreenPoint notebook adapter available by design, further strengthen our energy-efficient power adapters with leading silicon vendors. This new design is critical for energy efficiency and size of adapter application and cost and optimization. "On semiconductor Senior Vice President, automobiles and power products weiliansi (Andy Williams).
60W power adapter reference design as shown in Figure 3, whose main component is NCP1337 enhanced pulse width modulation (PWM) current-mode controllers. By monitoring the feedback pin of the controller, as long as the power requirements below the preset level, that is, into the ripple pattern. At the same time, through a combination of real current-mode modulator and detector for demagnetization, NCP1337 also ensures the full line on any load/line/critical conduction mode.
Latest blueprints on semiconductor provides truly energy efficient, all the function module also solves the power adapter, made a low standby power, and conform to the CEC, United States and European energy star requirements. Energy efficiency of design provides the 88%, energy consumption in standby mode less than 250mW (750mW most 60W adapter of standby energy consumption), further energy savings (the adapter is in standby mode most of the time). It is learnt that on semiconductor or other GreenPoint reference design scheme was launched at the end of this year, to cover more of the power supply.
Figure 3 60-Watt power adapter reference design
Increased investment in energy-saving products
To expand the capacity of energy saving products, reflecting its continued for the Office of the consumer, computing and electronic product development commitment to energy-efficient power management components, on semiconductor last year the United States power conversion IC Development Center in Chandler, Arizona officers and JVC BN-VF815 Camcorder Battery Charger area expansion 1 time, and nearly 20 new posts in the power engineering of integrated circuits. "Chandler the expansion reflects on semiconductor development center is committed to providing power to the electronics manufacturer programmes, to create energy-efficient consumer electronic products, and ultimately contribute to reducing home electricity expenses, save valuable energy and reduce pollution. Now, about consumers or enterprises of electric power 40% is by electronic devices inserted into the wall in the conversion phase the loss. Chandler Development Center for our goal is development of proprietary integrated circuit that reduce energy consumption by half. "Andy Williams said.
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| Thursday, 9-Feb-2012 02:36 |
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Design of solar power uninterruptible power
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Solar battery charge form continuous DC voltage output is a feature of this circuit, the circuit consists of constant current charger (IC1), over charging protection circuit (IC2 and T1) linear and switching regulators (IC3).
Constant flow charger IC1 of limit current for 60mA, once occurs on battery b of had charging (as in adequate too Sun irradiation Xia or load current smaller Shi), battery voltage rose, is P1 sliding end voltage rise, by can adjustable JVC BN-V312U Battery Charger regulator device IC2 for control, makes T1 saturated guide pass, by R5 and R7 bypass part or all current to to, LED1 glow, prevent had charging of occurs. Selection of output voltage, current and voltage regulator IC3 model (LT1300 or LT1301) and jumper S1 and S2 States.
As shown in the schedule, while S1 jumpers available on +5V (LT1300) or +12V (LT1301) the DC voltage output. +3.3V is available when the Nikon D100 Battery Charger S1 missed jumper (LT1300) or +5V (LT1301) output, same jumper or missed jumper to get on the S2 400mA, or 1 a of output current.
Ni-MH rechargeable batteries. When IC3 LT1300 two two batteries should be used. LT1301 should be used when the three batteries. Output voltage 9V, 100mA output current solar s. choke L1 800mA without saturation, the values in the schedule have been identified, D1 and D2 are Schottky fast recovery diode.
Circuit debug will first solar plate and battery disconnect and adjustable regulated power supply replace battery, adjustable power output on Panasonic Lumix DMC-FS37 Battery Charger the Terminal voltage of a table, such as LT1300 (use two two rechargeable batteries), adjustable power output at 3.2V. Adjust P1 until LED1 is lit, if LT1301 (three three rechargeable batteries), adjustable power supply on 4.8V, the same conditioning P1 until LED1 is lit.
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| Friday, 13-Jan-2012 01:22 |
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Owner information: maintenance of 11 tools
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Vehicles increasingly become an everyday means of transport, go out the road will inevitably encounter car problems when, for example, broke, running out of battery power, had a flat tire, and so on. Owners is needed at this time there is a well-equipped practical emergency kit. So what this emergency kit needs tools?
Car emergency tool package includes: folding reflective warning flags, nylon, tow rope, taking the fire line, inverter, cotton work gloves, multifunctional flashlight (batteries), automotive fuses, disassembly free repair tire tools, waterproof tape and insulation tape, fire extinguishers, 11 pieces such as air compressor required.
, Foldable reflective warning signs
This foldable reflective warning flag is extremely practical, in your car when problems need a stop check, 50 meters away, put it in the rear of Nikon EN-EL9A Battery Charger the car, reminding passers-by slowdown ahead. At the same time, not when warning signs that can be folded inside the car will not take up much space.
Second, nylon tow rope
To prepare a dragging at least 3 tonne truck trailer, so that when the car broke down to easily tow.
Three, taking over FireWire
When the car radio does not boot, which can be launched from a vehicle battery. Bold battery starting line, the maximum current is 200AMP, for displacement to 2500cc gasoline engines or emissions less than 2000cc diesel engines between battery use.
Use process to note:
Two cars cannot have any contacts in two-car electronic systems must have the same voltage.
If the batteries freeze, you cannot use the battery to start taking fire.
Before connection, two engines, car stereo, air conditioning will need to be turned off.
Connection procedures are as follows:
(1) the first line the red wires and pliers will be started in "saved cart" above the Red battery cathode.
(2) Red wire pliers and then plug the other end in the "rescue" above the Red battery cathode.
(3) wire clamp in black "was saved cars" black anode on the battery.
(4) wire clamp in black "rescue" on black anode battery.
(5) start the "rescue" engine, and Panasonic Lumix DMC-LX5 Battery Charger then start "being saved" engine. If was put cars still will not boot, it is necessary to check whether the metal contact with some bad.
When you finish after starting the engine remains to be removed in order to start taking fire, failure to do so may cause short circuits.
Removing wire procedures are as follows:
(1) first "saved cart" black wires removed.
(2) and "rescue" black wires removed.
(3) and "rescue" the red wires removed.
(4) and finally "rescued" the red wires removed.
Four-, in-car power inverter
Car inverter is able to convert the 12V DC and AC 220V AC with the same, for use by General Electric, is a convenient power converters for cars. Car inverter power supply in mobile use in DC to AC converter, will bring to your life a lot easier, is a standing offer of motor vehicle electronic equipment supplies. Via the car cigarette lighter output inverter can be a 20W or 40W until 150W, 80W and 120W power specifications. No matter how big the power inverter received through a connector on the battery.
To note here is that buying car inverter power supply, not corruption (high power), is based mainly on their own electrical appliances to use conditions to choose. If it is only to charge the mobile phones, digital cameras, digital cameras, and Panasonic Lumix DMC-FS35 Battery Charger occasionally in the car with a laptop, select power inverter for 150W power supply can be done; but if owners need regular out, or lovers of self-driving tour, over 200W of power inverter is the wise choice.
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| Tuesday, 13-Dec-2011 01:09 |
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Advent DV era of high definition full 1080P is gradually becomin
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With the increasing popularity of LCD, plasma, HDTV now has become an absolute high-end TV market in the mainstream. In order to cater to this trend, various digital products is also related to the initiation of the overall move closer to HD, recently, Sony, Panasonic, JVC, Canon, Samsung has released dozens of digital video camera in the autumn new products, the Panasonic Lumix DMC-FP8 Battery Charger proportion of the quantity of the products, there is no doubt that vendors have already begun HD DV as a future key directions of development. 1080i (interlaced) and 1080P (progressive scan) parallel, miniDV, hard disk, DVD discs, Blu-ray disc, as well as a variety of media such as Flash Flash storage technology of blooming everywhere, makes this fall's high definition digital video camera market seems hilarious exception. One industry source asserted that DV HD era, has fully arrived.
1080P high definition DV trends
Many consumers to contact HD products when manufacturers advocacy support "1080i" and support "1080P" feeling overwhelmed, especially when some manufacturers in propaganda, claiming that only supports 1080P true HD. Reporters interviewed a vendor on the matter of a technician, the technical staff said, 1080i and 1080P are recognized by the international digital HDTV standard, and 1080P is a de facto standard. Due to scan 1080i interlaced approach is adopted, and 1080P is scanned line by line, so as far as image quality, far more than 1080i 1080P elite. However, are now either China, Europe or Japan, 1080P signal source is not really there, even now many TV products already support 1080P HD specification, but in the case of no signal source, no doubt just a publicity stunt.
Specific to HD digital camera area, currently 1080i still is market of mainstream, since first paragraph civilian HD DV Sony FX1E was born so far, has has three years time, technology Shang has very mature, and support 1080P specifications of DV products until this year only real appeared, due to by storage capacity, and Nikon Coolpix P90 Battery Charger coding type of limit, even has support 1080P play of TV, but and 1080i compared to, advantage does not obvious, production cost also to high out many, This does not mean that the 1080P high definition DV is not good, but the design is too advanced, is not very practical. The technician said, 1080i video camera has been fully meet consumer demand for high definition images, but there is no doubt that 1080P HD DV would be the future trends.
DV storage technology continuously upgrade
High definition digital video camera to obtain quick development, portability, ease of use are the two had to focus on factors. From the big vendors launch new products in the autumn of this year, the miniaturization of the fuselage has become a focus on the development trend of Home HD cameras, largely benefited from the development of a variety of storage technologies.
At present, exactly what storage media will become the mainstream HD digital camera store, has been a debated issue, most manufacturers are in every direction to explore, such as Sony, have also launched after miniDV, DVD disc, hard disk HD camcorder, and recently launched a high definition DV based on Flash technology. Relatively speaking, miniDV although volume is large, post editing techniques are difficult, but there are high quality, low-cost advantage; hard drive, DVD discs, and Flash though DV is small, easy post-processing, but capacity is a bottleneck, due to the high definition image very large amounts of Nikon Coolpix S8100 Battery Charger data, making these types of storage of DV can only record a relatively short time. From industry trends, with the development of technology, Blu-ray disc, hard drive and Flash Flash has the potential to become the mainstream of future home HD digital camera storage media.
Buy DV multifaceted consideration should be
A dazzling array of high-definition digital camcorders product on the market, so how can choose? Price has been is consumer on household HD digital camera talked about up to of topic, Sony FX1E just appeared of when, price had up to more than 30,000 more Yuan, in then only is minority enthusiasts to enjoy to of high-end models, and until appeared fell below million yuan of products Hou, household HD camera market only JVC GY-HD100U Battery Charger ushered in has a real of gold period, now many HD camera as long as thousands of Yuan on can buy to, for economic conditions slightly better of general consumer, are can accept.
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| Friday, 11-Nov-2011 01:15 |
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Novices learn camera DV using the ten basic concepts
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When using digital video cameras, we often encounter some common saying used in DV, a moment when the two are not clear, here we are ten using DV to introduce common concepts, to help you master the basic knowledge of photography.
1, what is a digital camera shockproof feature?
"Earthquake" refers to a hand when shooting you can increase the stability of the image. At present, the earthquake can be divided into two systems, one optical earthquake, another for digital shock. Optical vibration is lenses floating in principle have a stabilizing effect, picture quality is quite good, almost like the original picture quality when no earthquake, but the earthquake's effect is not JVC GR-D370U Battery Charger obvious. In addition, earthquake preparedness for digital zoom in the movie, take the middle part of the film formation as the primary image, image for earthquake occurs around the remaining space because the image is enlarged, so poor picture quality, but earthquake works well.
2, the "screen special effects," including what kinds?
General digital cameras provide a variety of screen special effects, making family adds attractive style of video works. Choose Insert pattern, solarization, black and white, or brown mode, to increase the tonal effect interesting. Want to have wonderful impressions, and use negative technology (negative/positive reversal) or pastel mode, your video-object appears as a new attitude. Some models even lengthen or widen the model is available to change the landscape aspect ratio. 8 models in Sony picture special effects including elongated, widening, insert pattern, solarization, black and white, Brown, negative technology and pastel. Figure 1 for a negative effect.
3, what is "digital special effects"?
Digital special effects for the ordinary pictures more creative. Options include static, Flash dance movements, image overlay, towing nostalgic images, movies, or slow shutter.
4, how to do voice dubbing?
You can use a MIC Jack to connect the microphone to record audio, you can use the a/v connecting cable to connect your camcorder to a TV set to check the recorded image and the sound. Recording sound from the speakers issue. Please check sound using TV or headset. Intelligent accessory slot microphone can be used, with AUDIO/VIDEO Jack dubbing, dubbing with built-in microphone. AUDIO/VIDEO built-in microphone jack or complex.
5, what is the automatic exposure?
Camera aperture adjustment and automatic broken up in two ways, our automatic aperture setting. Camera with auto iris lens, according to the brightness of Panasonic PV-GS85 Battery Charger the photo-control lens aperture opening big or small, the CCD is properly exposed. With Auto Iris mode, as long as the camera at objects, the lens aperture is automatically adjusted to the most appropriate location, shooting images clear picture. Automatic aperture opening of large or small is mainly under the influence of absorbed light, illumination adequate time laps down, reducing the amount of light in order to prevent excessive exposure, depth of field depth, while shooting in a dark environment, large aperture can drive to increase the amount of light to avoid underexposed, depth of field shallow.
6, what constitutes a "programmed AE"?
Advanced programmed AE mode, selected for the different recording conditions ideal for Aperture. Choices include Spotlight mode, soft mode for portrait mode, sports, beach, sunset and ski mode and night mode or landscape mode. Some models even have low light shooting modes to choose from. Figure 2 Select picture for programmed exposure.
7, just how long the life span of camcorder battery?
Battery life is limited, the battery with the use of the increase in the number and the passage of time, its gradual decline in the capacity, when the battery significantly shorter time can be used, possible cause is the charging time of life. Please purchase new rechargeable batteries. Of the battery, battery life and methods of preservation and vary depending on operating conditions and environments.
8, what is the intelligent lithium-ion battery system?
Sony digital cameras use repeatable power smart lithium-ion battery systems. At the time of filming, allowance for smart lithium ion battery is displayed in minutes, allowing you to more accurately grasp the remaining recording time and battery residual. High energy lithium-ion battery with no memory effect, each time without discharge before charging, the battery capacity is not affected.
9, what is the SP and LP mode?
Cameras generally have two modes: SP and LP. SP (standardplay) refers to the standard play, LP (longplay) refers to the long play. In LP mode to Nikon Coolpix P300 Battery Charger extend recording time, play time, battery life, and to the recording add title, and so on. Extension of multiple different cameras differ. Popular 1.5 times and twice times. 1.5 times, using the LP mode available in 80 minutes of video recording on 120 minutes of video.
LP mode works with fewer tapes store the same number of images. Camera store speed is to be stated. In SP mode, for example, data stored in three-fourths inches per second video speed coming in. In LP mode, data storage speeds of one-second inches per second video. The same data will take up less space. LP mode is to reduce the expense of image quality, especially when you are using an older video, noise increases significantly in LP mode. If you need a lot of storage space, take a look at Sony and Panasonic's new camera. In SP mode, and some video recording capacity of more than two hours. Of course, prices are a little higher.
10, what constitutes a "built-in Super IR emitter"?
Infra-red transmission system, allowing you to manipulate digital video camera to play at any time, waive the regular camera and digital TV connection trouble. You only need to advance the unique infrared receiver (optional accessories) connected to the TV. Dang to for Samsung TL100 Battery Charger replay Shi, simply by digital camera of "LASER LINK" key, and will digital camera and the TV set in play mode, by digital camera of "play" key, transfer device will issued infrared signal, you will may in distance TV up 8 m far of situation Xia watch video replay, and without then using any connection line, real reflected "wireless" replay of fun.
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| Thursday, 13-Oct-2011 01:44 |
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Professional "gold rush" of commercial digital camera selection
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In the current friends to buy digital cameras, the vast majority belong to the family purchased the user, a small portion belonging to organs and Nikon Coolpix S8100 Battery Charger units purchased users, while remaining part of the users who are used for commercial purposes, which some users purchase the main celebrations are used to provide camera, such as wedding, birthday parties, etc.
Because current people of social activities increasingly more, this aspects of demand also increasingly Chemokine more, so this class friends offered of personal company of operating status General are also is good of, this also on attract has more of friends prepared join to celebration camera of industry among to, however, some new getting started of friends in acquisition digital camera Shi encountered has some problem--"purchased a paragraph what of products only for celebration camera of need does"? "The low prices of the product CD is finally burned out can satisfy our customers?" "Single CCD camera product models have ideal for celebrations?" …… Don't worry, today we have to simply talk about profit-DV selection, I hope to this friend can help!
A basic requirement of, and dealing in DV
Buy digital camera is used for the purpose of operating, the requirements for the machines cannot and the average family, the General's family wants to buy a small volume, light weight, low power consumption, easy to operate digital camera, and for profit-DV, these conditions may not be suitable, it is best to meet the following conditions:
Greater 1, form
As a profit-DV, it looks like some larger, preferably shoulder-launched product. Because such to let people think "professional sense" full, to for you of company attract more of JVC GR-D347U Battery Charger customer, imagine, if you took with a Department Sony HC85E and carry with a Taiwan Panasonic NV-MD9000 of another a company while to recruiting wedding camera business, so most people will select carry with Panasonic NV-MD9000 of company, although Sony HC85E of shooting effect is better had Panasonic NV-MD9000, but because understand DV of people after all is minority, Big machines and Panasonic NV-MD9000 celebration is an impressive, huh:)
2, manual functions more
For the average home user, easy-to-use automatic shooting features is their favorite, because by setting a good automatic shooting menu can film can meet the General family-friendly image, which is very convenient for home users. But for a business of DV products, rich manual features are Nikon MH-64 Battery Charger essential, have some photography experience they can manually adjust the camera's automatic shooting options regulation than better the image, so you can in a variety of shooting environments take wonderful pictures to meet many different needs of users.
3, night shooting capabilities are better
Celebrations are held during the night, for example, birthday party, bonfire, outdoor environment dark at this time, if there is no good external auxiliary light source is very difficult to produce a satisfactory image, but sometimes may just doesn't have the appropriate camera lights, so, we need to choose a night shot better in some machines. Usually for, camera of night shooting ability is and CCD image induction device of Panasonic SDR-H80 Battery Charger size is closely related to of, from actual camera effect see, equipped with large size CCD of machine is better Yu equipped with small size CCD of machine, normal light Xia difference may does not too does not obvious, but in light comparison dark of environment in the difference on comparison obvious has, screen of color, clarity are can see different, so recommendations you as possible in funds allows of situation Xia purchased CCD image induction device size larger of camera products.
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| Wednesday, 14-Sep-2011 01:42 |
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Portrait focal length applications-all
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Model of this equipment is used to shoot the latest 8 megapixels Canon D-SLR EOS 20D, and the EF 17-40mm f/4L USM, EF 50mm f/1.8, EF 70-200mm f/2.8L USM three wide-angle, in the distance and telephoto lens.
Not shoot wide-angle close-up
When shooting portraits, what lens to use, we must first consider the need to absorb more of the background. If I had the whole environment is very unique, then we may wish to consider a more wide-angle focal length, Model, and this can also capture more background. If both a lower shooting angle, horizontal shooting angle is more than able to demonstrate a sense of perspective, the visual impact will be even greater. Sometimes, if the Model of Nikon Coolpix S620 Battery Charger the hands, feet get some place closer to the camera, these parts because of the perspective of the relationship is even more slender. But the usual practice is to wide-angle lens "stretched" Model legs, "extend" method requires both hands to shoot with more daring ideas.
It should be noted that the beginner is not advisable to face close-up wide-angle lens Model, Model shooting too close to the face will form a "strong sense of perspective", the distance between facial features pulled away, and the face becomes wider, and sometimes will be very scary. On the other hand, when shooting with wide-angle lens, to JVC BN-VF733U Battery Charger minimize the angle of the shot above the Model, so pictures are "top-heavy." In the low-angle shooting, also pay attention to Model's head should not be elevated, so as not to take out the chin, neck and become hypertrophic.
Unique environment, you can use wide-angle focal length plus the low-angle shot.
If the Model legs closer to the lens, the effect will have a more slender.
With wide-angle lens, if the rise is too high Model will become swollen.
Telephoto beneficial to simplify the background
If the shooting environment is more messy, or you just want to focus on some special features, you can choose to take a longer focal length. Then only the remaining small background objects, we can accommodate the angle slightly to avoid unwanted background scenery, such as lamp posts, pedestrians. The use of Panasonic DE-A49C Battery Charger long focal length shot half-length or face close-up of very good, because the facial features of the Model seems more normal proportion, but the background is relatively clean simple, more suitable for beginners. If we have DC's over 300mm equivalent focal length lens, then you can create a little more shallow depth of field, the background to deceive into abstract patterns, to better highlight the Model beauty.
Use a longer focal length can be simplified background.
Long focal length is ideal for close-up photos.
Long focal length lens can capture a shallow depth of field.
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| Tuesday, 9-Aug-2011 13:28 |
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Mind of close racing and Ford Racing photography mirror God bles
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This year's most stuffy when Beijing, Chengdu should be more enthusiastic, but at this point, because you are holding a racing event here: Touring Car Championships in Chengdu, China station, then against the heat we get to here. In addition to Ford fleet wave flags and shout batthe cries-bang the drum for SB, we also have a secret mission ...
--AF-S sports photography of the secret mission the gods mirror Nikkor practical trial for 200-400mm f/4G ED VR II.
Do you want to catch whizzing racing? In addition to a professional digital SLR, you will also need a responsive mm telephoto lens. The end Nikon EN-EL12 Battery Charger of April this year, Nikon has released a sports and nature photographers of market-oriented professional-level constant aperture--AF-S Nikkor 200-400mm f/4G ED VR II telephoto lens, combined with continuous shooting speed is up to 11 per second (under the DX trim format) Nikon D3s full frame digital SLR cameras, is now in the sports photography of the heavy weapon. The racing we necessarily need this weapon to assist in shooting, then let us take a look at the real strength of the lens.
From good to better, second generation endoscopic technology evolution
From the name can be seen on, AF-S Nikkor 200-400mm f/4G ED VR II is a "second generation mirror", its predecessor is the rebuke AF-S Nikkor VR 200-400/4G IF-ED of the sports arena. Basic specifications of the two lenses and optical structure did not much change occurred, are 17-24 sets of complex structure containing 4 Ultra ED low dispersion lens, used to reduce the dispersion of telephoto lenses easily. As a professional camera, Nikkor 200-400mm f/4G has maintained a constant aperture of F4, before the internal focus design allows the lens group will not turn as the focus changes.
Is interesting due to the diameter of the lens group is too large for its high cost of distribution a UV lens, Nikon presented simply with the lens a huge mirror glass protection, users usually can be screwed in front of the camera to protect the lens group not subject to wear. Giant group not only UV protection before microscopic configuration of rising costs, other color filter to do so is also quite expensive, Nikkor 200-400mm Department of f/4G in the mirror behind ad hoc diameter 52mm Rotary-type NC filter, reduced user cost of purchased parts.
Lenses is so many ways and has maintained a consistent, so what are the differences? First of all, is the lens coating is more advanced. New generation of Nikon Nikkor 200-400mm f/4G used the latest nano-coating technology, Nano Crystal coating on the surface of the lens can appear significantly reduces ghost and flare, so image quality in any lighting conditions are not affected by the loss. Second is to use the new VR II anti-shake mechanism, you can make the camera than the shutter speed or slow shutter speed shooting about 4, and the first lens VR anti-shake effect only up to 3. Last is the addition of A/M mode (manual priority AF, AF preferred) so that the lens focus mode to achieve 3. Namely: to rotate on focus band activation when the AF M/A for manual focus mode (manual priority autofocus, MF priority), manual focus mode, and new af accidents can be avoided the A/M switch to manual focus mode (manual priority AF, AF preferred). We actually use, main difference between A/M and M/A model is found in AF mode, manually when focus band touch camera sensitivity of different, but Panasonic PV-GS80 Battery Charger subtlety, see real, Nikkor 200-400mm f/4G of the second generation is clearly after the advice of a lot of professional photographers have made improvements, more thoughtful user actions.
And generation of microscopic compared to a A/M focus option has been added, so sports reporters shoot more smoothly. It is focused by limit switches, anti-shake anti-shake mode and switch to select.
More close to the gate there are two switches, namely focusing operation selection switch and the voice control switch.
View more practical, for sports photography design
For sports photography or nature photographers, picture quality and ease of the balance of the two is important. Although Nikon as well as 200mm f/2, 300mm f/2.8, 400mm, f/2.8, lens, but at the time of shooting sport scenes if movement is vertical relationship with the photographer, then the view is changing. If you use only a fixed-focus lens, shooting the continuity of the obvious zoom lens than high, in late may need certain crop, causing loss of pixels.
Nikkor 200-400mm f/4G in full frame digital SLR camera Shang Coke segment is its physical Coke segment 200-400mm, and in using D3s of DX frame mode or DX camera (as D300s) Shi, equivalent focal length can reached 300-600mm, equivalent a support lens contains has 200-600mm, covers has Cosco Coke to super telephoto all Coke segment, and aperture are for Samsung WB650 Battery Charger constant of F4, this in composition of facilitate of Shang and will Coke lens comparable. "A top four or five", although its weight also reached more than 3 kilograms, but at the same time carrying several telephoto lens but relaxed does not know how many times.
Experience: facilitating high-quality sports photography dedicated lenses
Down a game, the black tube is the sun hot, I was already soaked with age, but use the lens fully and delightfully pleasure made me excited. Whizzing racing, pungent smell of rubber friction, and D3s high-speed continuous shooting of "a big" sound, full of sense of speed everywhere inside and outside the stadium. Only to get the game, you'll discover how exciting lenses Nikkor is 200-400mm f/4G, with the DX trim format D3s, focal length can be extended to 600mm, that is, between 200mm and can be covered, inside and outside the stadium any details will not escape its eye. If you like shooting sport, so the lenses can save you a lot of costs of purchasing several fixed-head and its Imaging will not let you down.
Rear lens is a Memory Set key on the right, to memories of lens to focus settings, need to appear often take a fixed distance of the target, may reduce the reaction time lens, for sports photography is a very useful feature.
Front of the lens with Nikon for the dedicated camera protection glass lens design to protect expensive lens group.
Configured with mirror made of a carbon fiber hood, light and strong, front of the lens hood by design has a round rubber edge, the photographer can simply shot erected on the ground, without causing harm to it.
After you remove the lens hood lens State.
Comprehensive rating: ★ ★ ★ ★ ★
No doubt, this is Nikon telephoto head boss, comprehensive performance is excellent.
Operational: ★ ★ ★ ★ ★
Press the key to meeting the needs of professional photographers of various thoughtful released A/M mode is more considerate of users.
Resolution: ★ ★ ★ ★ ★
Compared with light outlining Jiao Jing favourably, sharpness, and resolution is excellent.
Real shot effect: ★ ★ ★ ★ ★
Excellent imaging is meeting the demands of professional photography, camera pixel high some more strength.
Price: ★ ★ ★ ☆ ☆
Price compared to its predecessors, nearly 50,000 yuan price is slightly expensive.
Listen to listen to professional photographers how to beat racing
Although have fly off the handle you want to get some experience on the ground this morning how fabulous this legendary God mirror, but don't worry, we'll listen to professional racing photographer to talk about those things racing photography.
Racing photography and our daily take are very different, the biggest feature is the speed of motor sport, so we must keep the shutter speed at a very high level, of course, for some special effect shot, still need to make timely a slow shot.
With racing three years photography experience taught photographers snap, not only in imparting skills while also shooting sample as we explain.
Few tips teach you to shoot good racing
Good grasp of the shutter speed
If you want clear racing pictures, then we need to keep your shutter speed to 1/200 seconds or even higher, because even a little hesitation, it will instantly from your lenses in dust-proof.
Aperture selection is important
If you also want to keep around while shooting racing environment details, then you need to narrow the aperture when shooting for more depth, instead if you need to highlight the performance racing buzz, you can use a large aperture to shoot.
How equipment should be selected
Telephoto lens is the best choice for you, because the schedule is not in close contact with the track, so a good quality telephoto lens is required. In addition you also need a tripod, rain, Sun, and other equipment.
Position your perspective
Want to take unique pictures, first you have to have a different perspective, so may wish to look at the terrain in the course of filming, a good location can often take unexpected results.
Professional photographer shooting has also created their own results, it appears that if the city wants to shoot a special, additional photography tips line is also required.
Near bend is definitely a good place, where both can capture scenes of fierce competition, while relatively slow speed is also easier to shoot.
Due to the particularities of JVC BN-VF823 Battery Charger the racing venues, so you will need to prepare all possible conditions, such as preparing against rain, the Sun equipment. Since I did not prepare in advance, in the rain on a muddy path would suffer many losses.
Race car girl is absolutely a beautiful landscape, is already very competitive racing is all the more thrill.
Racing photography gods mirror real strength
There are guidelines to assist, shot up very easily, carrying machine we get to the racetrack next to a higher position, here is just after the start of the first continuous curve, believes this to be able to capture some satisfactory picture.
Focal length >200mm aperture >F7.1 shutter > >1/1000s ISO>200 white balance, auto
Rapid turning cars, shot composition in advance before, only to be targeted into the viewfinder start continuous shooting, look pretty easy focusing of the lens memory function at this time.
Focal length >200mm aperture >F7.1 shutter > >1/800s ISO>200 white balance, auto
Although is zoom head, but the sharpness in no uncertain terms, legible image magnification objective details.
Focal length >400mm aperture >F7.1 shutter > >1/800s ISO>200 white balance, auto
400mm is not the limit, in the use the DX trim format, can achieve the equivalent of 600mm super telephoto, meet the needs of long distance shooting.
Close contact with the racing
We also note that there are many shooting shoot friend spirits to come here in a State of excitement, but they tend to focus entirely on the game itself. In fact, there's also a lot of additional content worthy of our attention, such as race for life, some anecdotes on the pitch, and so on. Shooting the most important thing is to be good at discovering, was able to get pictures of people.
Changan Ford fleet had several riders have achieved a good record, but they are of very low profile in the life, approachable. Asked whether in everyday life would be so fierce when driving, expressed by several racers are not so smooth driving is their usual style.
The strength of the team are the key to winning
Racing is in fact a very team-oriented sport Ford team to achieve such a remarkable record of natural is also effective in a team for the excellent cooperation, in addition, there are qualities of drivers and racing performance. But they also say the current racing activity in the country are not very mature, site configuration is at least more humble.
Competition on the site is racing
In recent years, more and more people are starting to focus on the movement performance of the car, which would have been understandable, but some people are often at the risk of other people's lives openly on a street, road racing or speeding. The yidianji riders have expressed their views, they considered only on the track of competitive activity to be eligible to call racing, and advise those young drivers to smooth and safe driving.
Shooting--monopod
British extension CM25 monopod carbon fiber manufacturing, is both lightweight and durable, together with the BHD1 platform, is a perfect match for this large lens Nikkor 200-400mm f/4G. Tie in with the British after the extension table, shooting angle is more flexible, rugged construction even hoisted the lens on the back without problems.
Nikkor 200-400mm f/4G such a huge volume, light quantity not telephoto lenses, unless you have a medical examination of Governor Schwarzenegger, or basic out of handheld shooting (lens Nikon D3s body weight increases nearly 10 pounds). Especially when shooting sports, who need to shoot under field conditions flexible mobile flight, according to the goal of focusing far and near, and is likely to wait for a long time, in this case, a small sturdy monopod became essential equipment for shooting, and even can be said to be the only essential equipment.
Perhaps some may say tripod more stability, why not use a tripod? Yes, stable natural easier than monopod tripod camera, but the volume weight is larger, the mobility of the tripod is not strong, is not suitable for use in sports. Monopod can help the photographer on the one hand supporting the lens, reducing unnecessary physical exertion, when shooting fast-moving objects and more easy to use technologies such as coke. As for stability, quicker shutter speed for sports photography because most of the time, coupled with a camera anti-shake mechanism, so there is too much to worry about.
Introduction to Changan Ford fleet
Lift the CTCC China Touring Car Championship, you have to mention Changan Ford fleet. On February 15, 2006, Changan Ford teamed up with formula racing Development Limited (FRD), formally announced the establishment of Changan Ford Racing team. Fleet was established four years enjoyed top-level race car venues in China has made brilliant achievements. 2009 for Changan Ford won the fifth champion young riders Cao Hongwei station station was only 16 years old, created domestic sites match the record of youngest champion racers in history.
Changan Ford Racing prototypes: Fox
Ford Fox went public in September 2005, with stylish appearance, precision control, safety, comfort and high quality, immediately won the market's favor, Changan Ford's award-winning record sales. It uses the same rare level models in the front and rear independent suspension, configuration comparison kind. When used as a racing after the original lightweight handling, in order to get better performance.
Written in the last: carry the day, there is too much for the shoulders. While the weather like today and we had a joke, just at the beginning of the game under the continuous patter of raindrops with rain, tournament more than half of the storm, and Ford driver accepts the challenge and me and my equipment, in the context of rain, the Sun was able to ensure that the work was not easy, because my own body to strike.
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