Contents

MAGNIFICATION RATIOThe ratio between the focal length of a lens and the focal length of a standard angle lens. Indicates the magnification of the image when compared to an image from a standard angle lens.MANUAL IRISType of lens that requires manual focusing.MATRIX SWITCHERAdvanced type of switcher in which a signal from any input can be switched to any number or combination of outputs. Generally used in larger and more complex systems the matrix will usually al...

Glossary Of Terms (M - R) - CCTV

Glossary Of Terms (M - R) - CCTVMAGNIFICATION RATIOThe ratio between the focal length of a lens and the focal length of a standard angle lens. Indicates the magnification of the image when compared to an image from a standard angle lens.MANUAL IRISType of lens that requires manual focusing.MATRIX SWITCHERAdvanced type of switcher in which a signal from any input can be switched to any number or combination of outputs. Generally used in larger and more complex systems the matrix will usually also incorporate a range of additional advanced features.MICROWAVE TRANSMISSIONA method of transmitting signals using a microwave frequency link. Not affected by adverse weather but requires direct line of site. A licence may be required to operate a microwave frequency system.MODEMDerived from the term Modulate-Demodulate. A modem is used to convert between analogue and digital signal to then transmit and receive the signals over the PSTN network.MOIR PATTERNAn unwanted effect that appears in the video picture when a high frequency pattern is looked at with a CCD camera that has a pixel pattern close (but lower) to the object pattern.MULTIPLEX VIDEO RECORDINGThe condensed recording of more than one video signal on a single videotape, or hard disk drive.MULTIPLEXThe concept of transmitting several signals on a single channel.MULTIPLEXERA device that combines a number of signals into one. Often used in CCTV to describe a device that is primarily used to multiplex several video signals into one for the purposes of recording or microwave transmission. It can also refer to a fibre optics multiplexer which combines a number of video signals into one in order to transmit all of them via a single fibre cable.N/C AND N/O ALARMSRefers to Normally Closed and Normally Opened contacts. It is usually used to describe alarms in CCTV.NANumerical Aperture. A measure of the angular acceptance of light incoming into a fibre optics cable, in the form of a cone. It is expressed as the square root of the difference of the squares of the indices of the core and the cladding.NBSNational Bureau of Standards (USA).ND FILTERSNeutral Density filters are optical filters that attenuate the light a number of times. This attenuation is equal for all the wavelengths therefore it does not change the colour balance of an image, hence the term neutral.NITA photometric unit for measuring luminance. One nit is equal to one candela per square metre of a projected surface area.NOISEAn unwanted signal produced by all electrical circuits working above the absolute zero. Noise cannot be eliminated but only minimised.NTSCNational Television System Committee, an American committee that set the standards for colour television as used today in USA, Canada, Japan and a few other countries.O/POutput. Objective. The very first optical element at the front of a lens.OCULARThe very last optical element at the back of a lens (the one closer to the CCD chip).OSCILLOSCOPE(Also CRO, from "Cathode Ray Oscilloscope"). An electronic device that can measure the signal changes versus time. A must for any CCTV technician.PALStands for Phase Alternating Line, which describes the colour phase change in a PAL colour signal.PAN AND TILT HEAD(P/T head). A motorised unit permitting vertical and horizontal positioning of a camera and lens combination. Usually 24 VAC motors are used in such P/T heads, but also 110 VAC, ie. 240 VAC units can be ordered.PAN UNITA motorised unit permitting horizontal positioning of a camera.PHOTA photometric light unit for very strong illumination levels. One phot is equal to 10,000 luxes.PHOTODIODEA type of semiconductor device in which a PN junction diode acts as a photo sensor.PHOTO-EFFECTAlso known as photoelectric effect. This refers to a phenomenon of ejection of electrons from a metal whose surface is exposed to light. Photon. A representative of the quantum nature of light. It is considered as the smallest unit of light.PHOTOPIC VISIONThe range of light intensities, from 105 lux down to nearly 10-2 lux, detectable by the human eye.PINHOLE LENSA fixed focal length lens, for viewing through a very small aperture, used in discrete surveillance situations. The lens normally has no focusing control but offers a choice of iris functions.PIXELDerived from picture element. Usually refers to the CCD chip unit picture cell. It consists of a photo sensor plus its associated control gates.PLUMBICONThermionic vacuum tube developed by Philips, using a lead oxide photoconductive layer. It represented the ultimate imaging device up to the introduction of CCD chips.POLARISING FILTERAn optical filter that transmits light in only one direction (perpendicular to the light path), out of 360 possible. The effect is such that it can eliminate some unwanted bright areas or reflections, such as when looking through a glass window. In photography, polarising filters are used very often to darken a blue sky.POTSPlain Old Telephone Service, ie. the telephone service in common use throughout the world today. Also known as PSTN.PRESET POSITIONINGA function of a pan and tilt unit, including the zoom lens, where a number of certain viewing positions can be stored in the systems memory (usually this is in the PTZ site driver) and recalled when required, either upon an alarm trigger, programmed or manual recall.PRINCIPLE POINTAn optical term that refers to one of the two points that each lens has along the optical axis. The principle point closer to the imaging device (CCD chip in our case) is used as a reference point when measuring the focal length of a lens.PSTNPublic Switched Telephone Network usually refers to the "plain old telephone" service. Also known as POTS.PTZ SITE DRIVER(PTZ site receiver, or decoder). An electronic device, usually a part of a video matrix switcher, which receives digital, encoded control signals in order to operate pan, tilt, zoom and focus functions.QUAD COMPRESSOR(Also split screen unit). Equipment which simultaneously displays parts or more than one image on a single monitor. It usually refers to four quadrants display.RAIDRedundant Arrays of Independent Disks. This a technology of connecting a number of hard drives into one mass storage device, which can be used, among other things, for digital recording of video images.RAMRandom Access Memory. An electronic chip, usually known as "memory", holding digital information while there is power applied to it. Its capacity is measured in kilobytes.RANDOM INTERLACEA term describing a camera that has a free running horizontal sync as opposed to a 2:1 interlace type which has the sync locked and therefore has both fields in a frame interlocked together accurately.REMOTE CONTROLA transmission and receiving of signals for controlling remote devices such as pan and tilt units, lens functions, wash and wipe control and similar.RETMAFormer name of the EIA association. Some older video test charts carry the name "RETMA Chart".RF SIGNALRadio frequency signal that belongs to the region up to 300GHz.RG-11A video coaxial cable with 75 Ohms impedance and much thicker diameter than the popular RG-59 (of approximately 12 mm). With RG-11 much longer distances can be achieved (at least twice the RG-59), but it is more expensive and harder to work with.RG-58A coaxial cable designed with 50 Ohms impedance, therefore not suitable for CCTV. Very similar to RG-59, only slightly thinner.RG-59A type of coaxial cable that is most common in use in small to medium size CCTV systems. It is designed with an impedance of 75 Ohms. It has an outer diameter of around 6 mm and it is a good compromise between maximum distances achievable (up to 300 m for monochrome signal, and 250 m for colour) and good transmission.RMSAn abbreviation for Root Mean Square. All AC voltages are measured with multimeters that show the RMS value of the signal (not the peaks). For a sine wave signal such as the mains, the RMS value happens to be 1.41 times (square root of 2) below the peak values.ROMRead Only Memory. An electronic chip, containing digital information that does not disappear when power is turned off.RS-232A format of digital communication where only two wires are required. It is also known as a serial data communication. The RS-232 standard defines a scheme for asynchronous communications, but it does not define how the data should be represented by the bits, ie. it does not define the overall message format and protocol. It is very often used in CCTV communications between keyboards and matrix switchers, or between matrix switchers and PTZ site drivers. The advantage of RS-232 over others is in its simplicity and use of only two wires.RS-422This is an advanced format of digital communication when compared to RS-232. The basic difference is in the need for four wires instead of two as the communications is not single-ended as with RS-232, but differential. In simple terms, the signal transmitted is "read" at the receiving end as the difference between the two wires without common earth. So if there is noise induced along the line, it will be cancelled out. The RS-422 can drive lines of over a kilometre in length and distribute data to up to 10 receivers.RS-485This is an advanced format of digital communications compared to RS-422. The major improvement is in the number of receivers that can be driven with this format, and this is up to 32.

Computer Security: How Are Patches Used?

Computer Security: How Are Patches Used?

Patch sizes vary and may be as small as some kilobytes or go as high as a hundred megabytes and higher the larger the size, the larger the change the patch is bound to do. Typically, when media, such as pictures and sounds, are changed or added instead of program, files become rather large. This is usually seen in patches designed to update or modify computer games. Unlike software designed for initial installation process, patches generally are faster to apply. Some patches may be acquired from the manufacturers and sent to users in diskettes or discs, while others may be downloaded through the Internet. Patches that are downloadable could take longer to acquire depending on the connection speed. Most patches that are designed for operating systems and software for computer servers are created to fix important holes in the security system. Some operating systems allow automatic update or semi-automatic updating that allows the continual feed of patches whenever there are changes done by their authors. A lot of people, especially those in the corporate world, decline getting totally automatic updates because there were many experiences of patches causing glitches. Some software experts also believe that allowing totally automatic updates may let software companies acquire limitless control over peoples computers. Thus, varying degrees of automation has been offered in relation to getting patches. The use of totally automatic updates is rather more popular for the consumers because most operating systems, Microsoft Windows in particular, have added them as a support tool. Its creators have also set the automatic updates for Windows as default. Some users, especially network system managers, are very wary about installing patches. They put off applying them until they have clear proof that the fixes are stable. Most large patches or those that promote sudden significant alterations are distributed first with limited availability as beta tests for qualified developers who would know what to do in case something wrong happens. Free Scan! See how many errors your computer has, at http://www.registry-cleaners-reviewed.info Patches that are made to modify the programming of hardware are called firmware and are rather challenging because they entail complicated steps such as re-embedding sets of code on devices that involves that total modification and installation new codes for programs instead of just simple alterations to the existing version. Usually such patches perform delicate modification processes that could compromise the device if not installed properly, rendering it useless.

3 High-Tech Features Of The Apple Iphone

3 High-Tech Features Of The Apple Iphone

What's the big deal behind the Apple iPhone? It's expensive. It's revolutionary. But are its features worth the money?With all the popularity, you can assume everyones at least heard about it. What does the Apple iPhone feature and what can it do?#1: Multi-Touch TechnologyThe most outstanding feature is the iPhones radical multi-touch screen. The MT screen allows any mechanical button to appear on this high tech toy. It simply allows you to use your fingers to operate it. This is contrary to any other phone today, which either have mechanical keyboards or a stylus.By tapping the screen with your finger, you can navigate menus, dial phone numbers, write e-mail messages and likewise use the whole functionality of the popular gadget. The three-point-five-inch screen displays a keyboard for inputting text via multi-touch. Most consumers are seemingly skeptical about typing with the virtual keyboard, but Apple has predicted the common problems and has made sure the iPhone was constructed with features like automatic spell check and word prediction, not to mention an enhanced customizable dictionary. More so, the iPhone addresses the problems of typos commonly known to multi-touch usage by adding self-correction capabilities.When scrolling, the usual wheel is not found at the side of the gadget. The multi-touch screen functionality allows its owner to scroll by dragging a finger in the desired direction. The speed of scrolling is designed to be proportional to the speed at which you drag your finger.The multi-touch feature furthermore enables several more functions like multi-touch sensing for magnifying or reducing photos and even web pages. Using this feature, you can regulate object size simply by placing two fingers at the side of the object and then moving them, by dragging, either further apart or closer to one another. This feature does not distort images because images are initially scaled according to its original dimensions in the first place.Hands down, the iPhone is more intelligent than any other phone today.#2: Revolutionary SensorsThe gadgets sensors have the ability to detect changes to the iPhones environment. The sensors are minuscule yet absurdly powerful. The three major sensors include an accelerometer, sensor for ambient light, and a proximity sensor.The accelerometer sensor conveys the ability to detect any changes in the iPhones positioning. The iPhones screen display will actually rotate to portrait or landscape, while still packing its contents into the 3.5-inch screen. Because it changes the view according to ratio, images are not distorted among web pages, videos, or photos.The proximity sensors.These high-tech features detect the location of the iPhone with regard to the skin. When you make a call and hold the iPhone up against your ear, the display will automatically set to standby. This is important in that it serves two basic functions.One, by shutting off the display when not necessarily needed, this saves your batterys life. More so, this avoids accidental touches to the screen, which would otherwise be sensitive. As soon as the cell is moved away from your face, the proximity sensors react in this way.Ambient light sensor.Through the AL sensor, changes in the phones environment are detected and instantaneously adjust the displays brightness. Your iPhones display will always be well adjusted in regard to lighting.#3: Mac OS X Operating SystemThe hype behind the Apple iPhone increased when Mac fans found out the Mac OS X would be included. The Mac OS X is the operating system inside the latest Apple computers. On the other hand, the electronic doesnt have the complete functionality of the operating system. The entire OS X is too large to fit within the 4GB or 8GB internal memory. The iPhone contains a 500 MB version of the operating system.

PHP

PHP

The recent boom in field of Information Technology has seen a steep rise in the demand of trained professionals in PHP and MySQL. Software companies specializing in php mysql web development are always searching for skilled professionals for recruitment in several important projects. The current supply of PHP experts is much below par, in terms of potential growth in the industry.To train the educated work force in this regard various MySQL and PHP training courses have been developed. These courses provide elaborate training to the professionals for developing website with the usage of these languages. PHP Training ObjectivesTwo main objectives of php and mysql web development program are:To develop skills to create interactive and data-driven sitesSkill development for database creation in MySQL programmingPrerequisites For TrainingThe most important criteria for acquiring PHP training is thorough knowledge of HTML. The course should focus on any level in programming for teaching database creation. On the other hand there are courses for fresher in the field of php and mysql web development. Some institutes like Indus Net Academy, has launched ACE Web Developer course with the aim of teaching real applications in PHP and MySQL. These courses are beneficial for creating awareness among candidates about programming language. Course DetailsOnce you get enrolled into these training courses you can acquire knowledge in areas like PHP Programming Fundamentals, Strings Functions, Arrays Functions, HTML/CSS and Forms, File Handling and Email Handling in PHP, Object Oriented PHP and Session Handling etc. On the other hand, the ACE Web Developer course emphasizes on other programming languages such as MySQL Basics, Extended PHP, OOPS in PHP 5, Exception handling in PHP 5, XML / SOAP etc. Another vital aspect of these php mysql development courses are; 70% hands-on and 30% lecture ratio, as far as the training part of the course are concerned. By engaging the students in live projects the courses ensure that the students have a thorough understanding of the actual application of such programming languages. So if you have some knowledge about HTML, then you can get online training as well as work as a freelancer for php mysql web development. Some of the requirements essential for learning this programming language are:A personal computer at homeLinux, Windows, MacOS X, or Solaris operating systemWeb server (either Apache httpd or Microsoft IIS)PHP 5 or later with the PEAR extensions enabledMySQL 4.1 or later (5 or later recommended)Internet Explorer 6 or Firefox 2PHP programmers can now get quality work through the Internet from the freelancing websites. It is an open source language and is free to install and use. This is the main reason for the increase in the popularity of this language.

Wireless Microphones Buying Guide

A wireless microphone is all about convenience and a great sound quality at the same time. As the name suggests, a wireless or cordless microphone is a device that has no cables altogether. It is a higher version of a typical wired microphone apart from the fact that this model is cordless and bit bigger than the conventional microphone. This is so as it houses a battery pack and the transmitter. With some of the great technological features, this microphone version is nearly getting perfect in all the aspects like interference, range, battery life, and sound quality. That is why, in today's scenario, this unit is extremely popular and comes handy for any onstage performance.The "wireless microphone" is very much beneficial for the professionals as it gives them freedom to use the stage at will without the tangling of cables anymore. Such freedom is required for any music concert, presentation, karaoke, competitions, and many other such events, which calls for absolute flexibility without compromising on the sound quality. That is where it comes as an apposite solution. As it is having several benefits, so are the disadvantages of using this unit. For instance, it can help you to get rid of the cabling problems of a typical wired microphone, generally caused by constant moving and stressing the cables. But at the same time, many of the models offer a limited range that makes them usable within a range of 100 meters or so. Another typical problem still faced with some low-end wireless microphones is of the interference with other radio equipment or other microphones. The answer to this issue can be found in the new models well equipped with many frequency-synthesized switch-selectable channels. Another typical problem faced is of the operations time as it works on the battery.That is why we have some suggestions that will help you to choose the right kind of the unit from the available lot of products. Here is a buying guide for wireless microphones.Step#1Make a list of features you want in it. This can include range, operation time, no. of channels, and other important aspects.Step#2Once you have defined your requirement, you are now ready to search for the right model from the available range.Step#3Identify if a body pack microphone or a standard handheld microphone fits the bill. They offer the same features but can be used differently. In the body-pack microphone the body-pack is a small box, generally the size of a cigarette packet, houses the transmitter and the battery pack. The body-pack transmitter easily clips to the user's belt or can be worn on the body. Whereas a handheld wireless microphone is more like the conventional microphone with the basic difference being that in place of the cable this is bit bigger to house the transmitter and the battery pack.Step#4Once you have decided on that, it is time to look at the prices of the short listed microphones. Compare the products well and then make your choice.Step#5Before you finalize it make sure to take a trial if you are shopping physically. If shopping online, make sure to read the reviews carefully.

Keeping Your Mobile Sales Team Organized

Keeping a mobile sales team properly organized is a bit little juggling; you need to keep your eye on the ball, several of them, at all times. However, unlike a lone juggler, today's manager and his sales force in the field, can keep track of what's going on through dedicated computer programs that offer synchronization of data from multiple sources. These programs are known as customer relationship management programs, or CRM.One of the most efficient customer relationship management programs is the GoldMine Product Suite from FrontRange Solutions Inc. This suite has a number of component modules, each designed for specific tasks. The GoldSync component is the key to efficient contact management. It is capable of performing automated synchronization. This means that important information on customers can be updated throughout an organization regardless of where any of the members may be located.The mobile sales team of an organization will probably spend most of their time working in the field, or at home. From time to time, though, they may require to be temporarily back in the office. The office team, by and large, will be permanently based in the office. It has always been a serious challenge for any manager to ensure that all parts of the team have instant access to the most up to date customer data available. This is especially so considering how widely dispersed the mobile sales team might be at any given moment.FrontRange Solutions' Goldmine software and its GoldSync component in particular solves this dilemma. Unlike other Internet-based CRM programs, GoldSync allows a field operative to input data from anywhere, and at anytime of the night or day, and not only while connected to the Internet. This is because the software is desktop based, residing on the local machine and not on a remote server. Only when it is necessary to send and receive information to or from the database is it essential to go online.The level of security provided by GoldSync is impressive. There are no less than three levels of synchronization security. These operate through the use of a serial number, a site ID and optionally the validation of a user password can also be employed.The GoldSync administration center is where remote Goldmine users and their sites can be managed. The interface is in a familiar Windows Internet Explorer style. From here, contact information can be distributed to individual GoldMine users and sites. In order to control what content is sent where, filters can be set up. This can avoid any possible conflict between individual territories.The advantage of using GoldMine software is simply that a manager and the mobile sales team receives the same benefits and convenience, whether they are on the road or in the office.GoldMine software is not the only customer relationship management solution available. ACT! by Sage Software also operates to a high standard for anyone with customers and contacts who is in need of better organization. ACT! offers features and benefits similar to the Goldmine Product Suite.Other CRM programs can be web based through a web page interface. This means that mobile sales team users and office management must be connected to the Internet in order to use it. For the office staff this is usually not a problem. For the individual in the field, however, this may represent an unacceptable inconvenience, especially if he or she is frequently on the move.

Summary

MAGNIFICATION RATIOThe ratio between the focal length of a lens and the focal length of a standard angle lens. Indicates the magnification of the image when compared to an image from a standard angle lens.MANUAL IRISType of lens that requires manual focusing.MATRIX SWITCHERAdvanced type of switcher in which a signal from any input can be switched to any number or combination of outputs. Generally used in larger and more complex systems the matrix will usually al...