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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 32/2008 (Oct 6, 2008)
Recognition for DIPOL website. We are happy to inform you that recognized DIPOL site for a quality Internet service that deserves three stars - the sign of the high position among other awarded Web pages.
The mission of Gwiazdor Internet domain is positive influence on the development of Internet in Poland through promotion of valuable websites.
The 7th edition of "Engagingly about antennas" has been adjudicated. Everyone could exercise imagination, and the results show that this activity, as usual, brought a lot of interesting compositions with antennas, the objects that does not seem to be so inspiring.
The entries often present antennas as bridges linking various worlds:
As every year, they were carefully watched by fine art photographer from Krakow, Mr. Pawel Zechenter, who awarded the first and second prizes. Another award has been granted by the DIPOL Technical Department.
I place
- was awarded to Dariusz Maczynski for the aesthetic values of the series "In a distorting mirror":
II place
- was won by Mr. Andrzej Dragan for artistic values and leanness of artistic expression in "A couple":
The prize of DIPOL Technical Department
- went to Mr. Filip Wyporski for the picture "Out of love for antenna", showing the dominance of telecommunication technology over construction engineering.
The jury of the competition has awarded additional distinction to Ms. Anna Wojnicz for sociological insight in "Life is beautiful", as well as underlined the appeal of the pictures with our winged companions ("Solitude" of Ms. Weronika Zielinska, "This third one" of Mr. Janusz Pirzanski, "In camera flashes" of Ms. Agnieszka Wolicka, "Evening conversations" of Mr. Jarek Matla, and "We like it, will we fly away?" of Mr. Marek Niedoba).
There were 221 entries this year.

Tightness of satellite LNB housings. LNBs usually have two-level protection: outer plastic housing that protects the device mechanically and against direct streams of rain, equipped with gaps for draining of water, and internal watertight case that shelters the electronic circuitry of the device. So the gaps are left on purpose, to allow the water flow down.
The slit in the outer housing of an LNB and the water openings in its lower part
Interferences in TV antenna installations with modulators and broadband amplifiers. "I used 6-channel modulator Mixpol R95167 in a large antenna system. After combining the signals from the outputs of the modulator and from terrestrial antennas, it turned out that the pictures are snowy. After amplifying the mixed signal with a broadband amplifier, it appeared that some pictures are even worse. Why?"
With a large number of channels it is necessary to reduce the output level of the amplifier, below the rated maximum. In the case of 16 channels, the level should be reduced by 9.5 dB. For example, for an amplifier with maximum output level of 100 dBuV, in practice the signal can reach 90 dBuV. In the situation where the signals from the modulator are at the level of 60 dBuV, and some terrestrial TV programs 75 dBuV, the amplification factor should be reduced to 15 dB, which may not be sufficient for the distribution network. So it is necessary to choose amplifiers with a high maximum output level and independent inputs, enabling the antennas to be connected to one input of the amplifier (with adjustable gain), and the modulators to the second input (e.g. the amplifier CA-310 R904014 or MA-113 R82313). A very good solution is also application of channel amplifiers of ZG-401/601 series, allowing to adjust the optimum output level separately for each channel.
CCTV systems for historic buildings. Installation of CCTV devices in historic buildings is a delicate issue, due to the risk of disturbing the historic heritage. The conservators often do not agree on any cables. A good solution is to implement a wireless monitoring system.
For such CCTV system we can recommend wireless cameras PiXORD P400W K1132 with built-in WLAN interface. They cooperate with access points, e.g. Linksys WAP54G N2780. The wireless connection of the cameras and AP makes a single cell. In a building or historic site there can be implemented many such cells, linking the APs with a switch.
The managing center of the system can be based on a PC with NUUO software pack, which provides a variety of tools for live monitoring, recording and control of the whole IP CCTV system.
Wireless Network Camera: Pixord P400W (MJPEG/MPEG4)Access Point: Linksys WAP54G (54 Mbps 802.11g)MPEG4 IP Camera: Pixord P400PoE
The structure of wireless IP CCTV system
ULTIMAX - DVRs for demanding customers - mobile monitoring with cell phones and palmtops. This feature of CCTV system may be very useful for many users.It allows to access the system from anywhere in the world - from any place with reliable cellular service.

This function of ULTIMAX DVRs has been tested by the manufacturer for Nokia 7610, N72, N73, N75, N95 and Samsung E848. In the Download section, at the tab ULTIMAX, there are available two applications: "Mobile Surveillance Client" and "Windows CE &Windows Mobile JVM", allowing to monitor the chosen spots via the compatible mobile phones.
A palmtop with the image transmitted from ULTIMAX DVR
CCD vs. CMOS. One of the key components of any camera is its image sensor, where the light falling through the lens is converted into electrical impulses.
In the market there are cameras equipped with CCD (Charged Coupled Device) and CMOS (Complementary Metal Oxide Semiconductor) sensors. What is the practical difference between the two kinds?
The CCD sensors are used in majority of typical CCTV cameras with standard resolutions. They are usually the most expensive components of the cameras. CCD technology is comparatively complicated and expensive.
CMOS technology is newer and has a number of advantages: lower costs of the sensors, possibility of using higher resolutions, better control of exposition, possibility of partial exposition, lower current consumption, progressive scanning.
The development of CMOS sensors is still in the focus of electronic industry. The components are used in cell phones, PDAs etc. So far, CCD sensors have better sensitivity and provide WDR (Wide Dynamic Range) function that enables to employ them in virtually any conditions.
Color Day/Night Camera: SN-586C/B WDR Pixim (w/o lens, mechanically switching IR filter)
Megapixel IP Camera: IQinVision IQ755 <br />(5.0 Mpix, Day/Night, PoE)
Sunell M11208 camera with Pixim WDR sensor
IQinvision K1433 camera with CMOS 5.0 Mpix sensor
The significance of connectors in CCTV systems. Every connector, even the best one, causes degradation of the signal. The basic rule is minimizing the number of connections in the transmission channel.
Usually manufacturers of connectors give two important parameters describing loss of signal. The first, Voltage Standing Wave Ratio (VSWR), informs about which part of the signal is reflected back to the source of the signal. Typically it should be less than 1.5, i.e. 4% of the power of the transmitted signal. The second one is Insertion Loss, or attenuation of the signal, which should not exceed 0.2 dB, i.e. 0.5% of its power.
The connectors used for the WLAN antennas mounted outside buildings have to ensure proper protection against penetration of water. It is a fundamental issue for the efficiency of the transmission - a drop of water which penetrates the connector and cable shielding can reduce the output power even by half, converting it into heat.
There are available on the market compression BNC connectors E8293, which, for the band used in CCTV, have VSWR <1.03 and Insertion Loss <0.1 dB. Both the materials used and the construction make the connector fully protected against water.
They are easy to mount - after some practice it takes less than 20 seconds.

Instructions on how to prepare CAMSET cable and compress BNC connector E8293

Instructions on how to install compress BNC connectors <br />onto CAMSET cables
Compressing BNC connector E8293
Technologic - a new family of WLAN antennas available in DIPOL. The antennas of Technologic are used for creating efficient and reliable wireless networks operating in 5 GHz band. The antennas have been made of high-quality materials and components that guarantee high and stable parameters. There are available panel antennas A73502 (23 dB) , A73551 (19 dB), and sector antenna A73513 (17 dB). A novelty on the market is "Arka" Dual, combining the panel antenna A73521 (19 dB) and sector device A73523 (17 dB) - two antennas in one housing.
Distinctive features:
  • CE1471 certified
  • durable plastic covers resistant to UV radiation
  • low-loss antenna connectors with improved shielding (Teflon and gold)
  • specially designed brackets and other mounting elements made of rustproof materials, allowing easy assembling and long-term durability
  • active components protected against the aging process with special protective layer
The Technologic antennas offered by DIPOL
Panel Antenna: Technologic 5G-23D (5GHz 23dB)
Sector Antenna: Technologic 5G-17SV<br />(5GHz 17dB vert. pol.)
Panel Antenna: Technologic ARKA Dual 5G-19D (5GHz 19dB)- CLEARANCE SALE!
Sector Antenna: Technologic ARKA Dual 5G-17S (5GHz 17dB)
Panel Antenna: Technologic 5G-19D (5GHz 19dB) <br />with expanded housing
Panel antenna Technologic 5G-23D (5GHz 23dB)
Sector Antenna Technologic 5G-17S (5GHz 17dB)
Technologic ARKA Dual 5G-19D (5GHz 19dB)
Technologic ARKA Dual 5G-17S (5GHz 17dB)
Panel Antenna Technologic 5G-19D (5GHz 19dB)
with expanded housing
Problems with WLAN range. The solution to inappropriate quality of service can be use of suitable antenna.
For home and SOHO applications we can recommend a number of popular antennas:
  • omnidirectional antenna TP-LINK TL-ANT2405C (5dBi 2.4GHz) A72713,
  • directional indoor panel antenna ATK-P1/2.4GHz (8 dBi) A71290.
Indoor Omnidirectional Antenna: TP-Link TL-ANT2405C (2.4GHz, 5dB)
WLAN Wi-Fi Indoor Panel Antenna: ATK-P1/2.4GHz (8 dB, 2m cable &SMA/RP, white)
indoor antenna TP-LINK
TL-ANT2405C (5dBi 2.4GHz)
Indoor panel antenna
(8 dB, 2m cable &SMA/RP)
In practice, to extend the range of wireless network or improve service quality, the antenna TP-LINK TL-ANT2405C 5dBi 2.4GHz A72713 shoud be connected to the Access Point, and the antenna ATK-P1/2.4GHz 8 dBi A71290 to the wireless adapter.
We have written about:

Problems with implementation of LAN? - Let's build WLAN. Internet access is nowadays indispensable functionality of every office block, hotel or warehouse. When the building is not equipped with wired LAN infrastructure, the quick, cheap and effective way of solving the problem is wireless network...
- archive DWR of Sept. 17, 2007

ULTIMAX - DVRs for demanding customers - maps in remote client software. Distributed video surveillance systems and systems with a large number of cameras should enable the operator to easily locate the camera capturing the image, or the sequence of cameras that follow a moving object...
- archive DWR of June 16, 2007

Lossless splitting of cable TV signal for multi-room TV/video installations. Most of antenna amplifiers cannot be used for this purpose, due to unspecified parameters in the special cable channels. The void is filled by the RF amplifier AI-223 R90452...
- archive DWR of Oct. 15, 2007

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