Ccd Weather
Glossary Of Terms (M – R) – CCTV
MAGNIFICATION RATIO
The 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 IRIS
Type of lens that requires manual focusing.
MATRIX SWITCHER
Advanced 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 TRANSMISSION
A 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.
MODEM
Derived 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.
MOIRÉ PATTERN
An 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 RECORDING
The condensed recording of more than one video signal on a single videotape, or hard disk drive.
MULTIPLEX
The concept of transmitting several signals on a single channel.
MULTIPLEXER
A 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 ALARMS
Refers to Normally Closed and Normally Opened contacts. It is usually used to describe alarms in CCTV.
NA
Numerical 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.
NBS
National Bureau of Standards (USA).
ND FILTERS
Neutral 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.
NIT
A photometric unit for measuring luminance. One nit is equal to one candela per square metre of a projected surface area.
NOISE
An unwanted signal produced by all electrical circuits working above the absolute zero. Noise cannot be eliminated but only minimised.
NTSC
National 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/P
Output. Objective. The very first optical element at the front of a lens.
OCULAR
The 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.
PAL
Stands 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 UNIT
A motorised unit permitting horizontal positioning of a camera.
PHOT
A photometric light unit for very strong illumination levels. One phot is equal to 10,000 luxes.
PHOTODIODE
A type of semiconductor device in which a PN junction diode acts as a photo sensor.
PHOTO-EFFECT
Also 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 VISION
The range of light intensities, from 105 lux down to nearly 10-2 lux, detectable by the human eye.
PINHOLE LENS
A 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.
PIXEL
Derived from picture element. Usually refers to the CCD chip unit picture cell. It consists of a photo sensor plus its associated control gates.
PLUMBICON
Thermionic 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 FILTER
An 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.
POTS
Plain Old Telephone Service, ie. the telephone service in common use throughout the world today. Also known as PSTN.
PRESET POSITIONING
A 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 POINT
An 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.
PSTN
Public 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.
RAID
Redundant 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.
RAM
Random 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 INTERLACE
A 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 CONTROL
A transmission and receiving of signals for controlling remote devices such as pan and tilt units, lens functions, wash and wipe control and similar.
RETMA
Former name of the EIA association. Some older video test charts carry the name “RETMA Chart”.
RF SIGNAL
Radio frequency signal that belongs to the region up to 300GHz.
RG-11
A 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-58
A coaxial cable designed with 50 Ohms impedance, therefore not suitable for CCTV. Very similar to RG-59, only slightly thinner.
RG-59
A 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.
RMS
An 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.
ROM
Read Only Memory. An electronic chip, containing digital information that does not disappear when power is turned off.
RS-232
A 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-422
This 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-485
This 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.
About the Author
Instrom Limited is an independent security consultancy set-up in 1998 to provide a range of impartial security consultancy services to commerce, industry and the public sector. Business Security Consultants
Should I become a teacher or a nurse?
I am trying to decide weather to become a teacher or a nurse. I like both careers but teaching is something I am just considering I’ve wanted to go into nursing since I was a freshman. (I am a junior in high school) I never considered teacher until I started teaching a CCD (or also called Religious Education) class once a week and now I want to go into teaching but there is this part of me that really wants to be a nurse. It’s like I sort of want to be a teacher but I don’t I sort of just like doing this and not sure if I want to make it my career choice.
Any Help?
If I do go into nursing I want to be a pediatric nurse so I can work with kids.
If I am a teacher I want to be an elementary school teacher.
I think it’s Great that you want to work with Kids either way. I even love kids. But teaching them you need a lot of patience. That’s cause they are just learning everything. But if being a nurse is what you had wanted to do for a long time sometimes it’s best to go with your “gut” feeling. I think you should be a nurse. So that why you are also helping kids get better and all that stuff. So go ahead and go be that inner nurse you want to be!!
$ 116 US, Weatherproof Night Vision CCTV Super HAD Sony CCD Camera – (PAL), 1st Shopping Channel
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Aposonic A-CDBIV07 1/3″ Sony CCD CCTV All Weather Security Camera $110.99 |
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VONNIC VCD546B Super HAD CCD II Effio-E DSP Weather Proof Dome Camera $102.03 |
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Weather proof Dome Cam SONY 1/3″ CCD Effio-E DSP 2.8 ~ 12mm Lens 35Pcs IR LEDs $99.69 |
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35Pcs IR LEDs SONY 1/3″ CCD Effio-E DSP 2.8 ~ 12mm Lens Weather proof Dome Cam $99.59 |
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VONNIC VCD546B Super HAD CCD II Effio-E DSP Weather Proof Dome Camera $116.02 |
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1/3″ Sony super HAD CCD 480TVL array led weather proof camera $65.00 |
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1/3 Sony Super HAD CCD 2.8-12mm IP65 Weather-proof 42IR 130FT 480 TVL Camera $85.99 |
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1/4″ Sony CCD 480TVL Weather Outdoor CCTV Security Camera /w 3.6mm Len 26 IR LED $39.95 |
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600TVL 1/4″ Sony CCD CCTV Outdoor Weather Proof Security Camera 3.6mm 26 IR LED $60.00 |
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HEATED REAR VIEW CAMERA BACKUP COLOR CCD NIGHT VISION HEATER WINTER COLD WEATHER $119.99 |
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VideoSecu Day Night Vision Outdoor CCD CCTV Security Dome Camera, Weather-proof $85.19 |
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VideoSecu Day Night Vision Outdoor CCD CCTV Security Dome Camera, Weather-proof $85.19 |
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NEW CLOVER HDC-518 DAY/NIGHT WEATHER-PROOF COLOR CCD CAMERA WITH IR LEDS $274.18 |
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CCTV 1/3″ Sony super HAD CCD 480TVL weather proof array led perfect night camera $85.00 |
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VONNIC Outdoor Weather-Proof 24 LED Infrared Bullet Camera w/ 480TVL, Sony CCD $41.99 |
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600TVL Night Vision Cameras 70M IR All-weather Outdoor Waterproof HD SONY CCD $119.99 |
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All Weather Dual 1/3” Sony CCD 540TVL Night Vision Bullet Camera 50m IR $139.99 |
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36 LED VONNIC Outdoor Weather Vandal Proof IRDome Camera 520TVL 1/3in CCD NTSC $81.99 |
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520TVL Sharp CCD IR infrared LED Outdoor Security Camera CCTV Weather Proof WAL $42.00 |
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520TVL 4 Sharp CCD CCTV InfraRed LED 23 Pc Outdoor Security Camera Weather Proof $150.00 |
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Swann Security SWA31-C5 Alpha C5 Weather Resistant CCD 4 Camera Pack 65Ft $390.09 |
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Swann Security SWA31-C6 Alpha C6 Weather Resistant CCD 8 Camera Pack 65Ft $737.87 |
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Farenheit CCD-1 (ccd1) Weather Proof Rear View Backup/Reverse Color Camera $79.99 |
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Waterproof IR Dome Camera 1/3” SONY CCD 600TVL HD OSD All-Weather 3.6mm Lens $86.50 |
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1/3” SONY CCTV CCD IR Outdoor Security Camera Weather Proof 600TVL Free Power $190.00 |
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420TVL All Weather Sony CCD Color Camera 20m IR Night $64.99 |
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CCTV All-Weather Security SONY CCD Infrared IR Camera $47.20 |
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540TVL 48 LEDs 30m IR CCTV Security Camera All Weather Day Night 1/3 Sony CCD $67.64 |
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RAINBOW MWC4241NBSF WEATHER PROFFED CCD CAMERA $225.00 |
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540TVL All Weather Sony CCD Color Camera 20m IR Night $88.99 |
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540TVL All Weather Outdoor Sony CCD Color Camera 30m IR $68.50 |
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Sony CCD Armored Vandal Weather Proof Dome CCTV Camera $99.00 |
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SOUNDSTREAM VCCD-1 FLUSH MOUNT CAR REARVIEW WEATHER PROOF COLOR VIDEO CAMERA $108.15 |
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Sony CCD Sensor Dome Camera Vandal & Weather Proof $99.95 |
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Dual 1/3” Sony CCD 420TVL All Weather Outdoor 50m IR Security Camera CCTV $130.66 |
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480 TVL Bullet Camera 3.6mm Fixed Lens 1/3″ Sony Super HAD CCD Weather Proof $65.00 |
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600TVL All Weather Sony CCD Color Camera 20m IR Night $95.99 |
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WDR 700TVL HD SONY CCD Effio-P 70 Meter IR Outdoor All Weather CCTV Camera $185.99 |
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Aposonic A-CDBIV07 1/3″ Sony CCD CCTV All Weather Security Camera $110.99 |
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Sony CCD Helmet Cam Weather-Proof 520 TVL 3.6 mm New $69.98 |
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Sharp CCD Helmet Cam Weather-Proof 420 TVL 2.8mm New $78.98 |
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520 TVL 3.6 mm Sony CCD Sensor Helmet Cam Weather-Proof $54.98 |
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520 TVL 2.8 mm Sony CCD Sensor Helmet Cam Weather-Proof $69.98 |
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Helmet Sports Cam 3.6mm CCD Weather-Proof 420 TVL New $78.98 |
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Q-See Winter All Weather CCD Cameras 2 Pack QSDS148DH2 $359.99 |
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Vonnic VCD520W 1/3″ Sony Super HAD CCD II Night Vision Weather Proof Dome Camera $56.11 |
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Vonnic VCD520W 1/3″ Sony Super HAD CCD II Night Vision Weather Proof Dome Camera $56.11 |
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(4) Pack Sony LED 24 Pcs Security Bullet Outdoor Camera 540TVL Weather Proof CCD $170.00 |
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SECURITY LABS SLC-154C WEATHER-PROOF CAMERA WITH MICRON PITCH CCD $162.99 |
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600TVL 3.6mm SHARP CCD IR 20M 60ft Feet All-Weather CCTV Bullet Bracket Camera $75.00 |
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LTS LTCMR601H 1/3in Sony Super HAD CCD IP65 Weather Proof 100FT Bullet Camera $72.99 |
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600TVL 3.6mm 1/3 SHARP CCD IR 60FT Feet All-Weather CCTV Bullet Bracket Camera $75.00 |
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4X 540TVL 36 IR 98FT 1/3 SONY HAD CCD 2.8~10mm Lens Weather Proof IP66 Camera $471.99 |
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Mini IR LED Weather-proof 420TVL Sony CCD Color Camera $62.89 |
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1/4 Sony CCD Day Night Weather Resistant Bullet Camera $99.00 |
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540TVL 36 IR 98FT 1/3 SONY HAD CCD 2.8~10mm Lens Weather Proof IP66 Camera $126.19 |
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SONY EFFIO 700TVL CCD VARIFOCAL WEATHER PROOF DAY NIGHT CCTV SECURITY CAMERA x4 $516.57 |
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Security Labs Slc-154C Weather-Proof Camera With Micron Pitch Ccd $131.17 |
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Weather Proof Infrared License Plate 600TVL/6-60mm AVF Lens Camera S-CCD II $239.00 |
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Weather-proof IR Dome Camera DNR Dome Day/Night w 1/3″ SONY Super HAD CCD $698.00 |
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700TVL 120 ft IR 1/3 Sony Exview HAD II CCD(960H) IR7084VFB outdoor weather $109.99 |
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1/3 Sony Super HAD CCD IP65 Weather-proof 2.8-12mm 42IR 130FT 480 TVL Camera $86.29 |
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VONNIC VCD546B Super HAD CCD II Effio-E DSP Weather Proof Dome Camera $102.03 |
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VONNIC VCD546B Super HAD CCD II Effio-E DSP Weather Proof Dome Camera $102.03 |
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Vonnic VCD520W 1/3″ Sony Super HAD CCD II Night Vision Weather Proof Dome Camera $56.11 |
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Sony CCD IR LED Weather-proof Outdoor Color Car Camera Front View for Security $73.50 |
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600TVL 2 Professional 1/4″ SONY CCD Surveillance Camera DVR System Weather Proof $350.00 |
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LTS Day and Night IP66 Weather-proof IR Camera, 1/3 Sony HAD CCD, DVC-CMR613 $92.99 |
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540TVL Waterproof CCTV Security Camera 30m IR All Weather 1/3 Sony CCD Chipset $61.00 |
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Sony 1/3″ CCD Bullet Camera 2.5~9 mm Lens Weather Proof $199.95 |
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LTS CMR819 1/4in Sony HAD Color CCD 12IR LED Weather-resistant Bullet Camera. $43.99 |
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SONY 1/3″ CCD Effio-E DSP 2.8 ~ 12mm Lens 35Pcs IR LEDs Weather proof Dome Cam $99.99 |
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SONY CCD 70m IR Night Vision 540TVL All Weather Outdoor Security Camera $102.50 |
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Vonnic VCD520W 1/3″ Sony Super HAD CCD II Night Vision Weather Proof Dome Camera $70.10 |
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1/3″ SONY CCD 540 TVL DAY & NIGHT INFRA RED 3.6mm WEATHER PROOF x4 $348.32 |
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All-weather Waterproof 1/3″ SONY CCD sensor 540TVL IR Bullet Security Camera $57.50 |
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NEW Farenheit CCD1 Weather Proof Rear Security Camera $78.99 |
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Security Labs Weather-Proof Camera with Micron Pitch CCD $135.81 |
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Sony CCD Weather-Resistant Wall Mount Outdoor Low Lux Color Camera $49.89 |
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1/3inch Sharp Black and White CCD Weather Resistant IR Camera, 420 TVL $28.65 |
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540TVL Waterproof CCTV Securitiy Camera All Weather 70m IR Range 1/3” SONY CCD $161.50 |
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1/3 Sony Super HAD CCD 2.8-12mm IP65 Weather-proof 42IR 130FT 480 TVL Camera $87.09 |
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SOUNDSTREAM ANGLE MOUNT WEATHER PROOF 1/3″ CCD 1 LUX LOW LIGHT CAR BACKUP CAMERA $108.15 |
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SOUNDSTREAM VCCD-1 WEATHER PROOF REARVIEW REVERSE LOW LIGHT COLOR TRUNK CAMERA $108.15 |
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540TVL SONY CCD All-weather Waterproof IR CCTV Camera $109.99 |
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Swann Alpha D03C5 H.264 8 Channel DVR & 4 CCD Weather R $799.95 |
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600TVL 42Pcs IR 105ft SONY 1/3″ CCD 3.6mm Lens Weather-resistant Bullet Camera $98.09 |
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600TVL 42Pcs IR 105ft SONY 1/3″ CCD 3.6mm Lens Weather-resistant Bullet Camera $98.09 |
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600TVL 42Pcs IR 105ft SONY 1/3″ CCD 3.6mm Lens Weather-resistant Bullet Camera $98.09 |
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600TVL 42Pcs IR 105ft SONY 1/3″ CCD 3.6mm Lens Weather-resistant Bullet Camera $98.09 |
