Category:
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
0
1
2
3
4
5
6
7
8
9
Position:IcFull.com » IC Electronic information » Category: T

IC Electronic information

The whole era of digital television distribution network maintenance switch

In Electronic Infomation Category: T | on April 13,2011

1 Introduction After the transfer times for the whole

definition, I think: the end of the whole turn, the analog signal is turned off, but for various reasons, the original portion of cable subscribers do not always have time conversion, in a very long time to convert one after another . This time is called after the entire transfer times. Existing digital television transmission network, broadly speaking, is still the original cable television network.

Recent years, with the ever-changing broadcasting technology, EPON + EOC, EPON + LAN, CMTS / CM and X9C104S datasheet and other new technologies are emerging and X9C104S price and put into practice, but in general, but still made a few years ago and X9C104S suppliers and has been widely used HFC network.

The last two years, the entire transfer of digital television and radio and television network business development, multi-functional requirements, have carried out all over the digital transformation of radio and television networks, Taizhou has been upgraded to 860MHz two-way network, and in some older residential , to transform the main trunk to increase the number of optical node, to optimize the entire route system, the next station only to bring a light amplifier, try to keep straight with light user workstation, the original Lou Dong Extension and the passive device can be retained , replace the amplifier two-way amplifier 860MH z, carried by each optical node is not more than 300 users. According to SARFTs requirements, current analog TV sets have been related to 6, the transmission of more than 140 sets of digital radio and television programs, and some interactive services and other value-added services have been gradually carried out. The main work of the overall transition from the transfer line to the sporadic users to install and carry out maintenance and value-added services up. I engaged in the cable television network maintenance and management work for more than ten years, the whole turn for the better after the end of how to safeguard digital television transmission network gained some experience, a little experience, for reference.

2 different grades of cell network maintenance mode

2. 1 new district network maintenance

Figure 1 is a new residential block diagram of a typical building nets. Cell lines are pre-buried, the use of EPON + active EOC way. Workstations light engine room equipment, EOC head-end, ONU, power supply and 1 table, EOC head depending on the number of two-way business users to increase (for the time being set 1 set).

Optical workstation for the two high output, independently adjustable, with the user directly to the output level when transferred to 112 ~ 115 dBV, drive amplifier adjusted to 108dBV, due to the higher output level, the output of the amplifier can drive to set up a port over-current branch, isolated part of the signal to drive users to another part for the amplifier, amplifier for the two high output level 106 ~ 108 dBV, each unit amplifier are used to Lou Dong QR540 cable.

Lou Dong in a centralized distribution, the distributor has 8,10,12 several, into the family line using four shielded RG6 cable, into the household level to ensure that the 72 dB V or more.


Figure 1, the new district distribution network

On the high output of the problem, there are articles required under the proposed station on the light distribution amplifier should be used extending the low-gain amplifier with low output of this statement, I challenge this a bit. This paper presents the workstation driven by the light amplifier is equivalent to the nominal output level trunk amplifier amplifier, we all know, trunk amplifier gain 20 ~ 22dB, the output level is 92 ~ 94 dB V, if a building has 3 units, each 12, total 36 households, each household level is 72 dB V, together with the amplifier unit to Lou Dong line loss, the trunk amplifier can drive up to two floors, the user driven too.

I think it is non-linear optical amplifier workstations and indicators are improved, not to mention the digital transformation, the light only to drive a station under the amplifier, as described by the author in front of workstations light output level at 108 dB V This low output dry than put the user-driven increase of 8 to 10 times. For the nonlinear index of whether the national standard, we can come to test:

Light station indicators: the output level is 112 dB Vs case, the nonlinear index of CTB = 67 dB, CSO = 62 dB, 108 dBV output in the case of indicators for the CTB = 75 dB, CSO = 66 dB; amplifier indicators: output level 104 dBV case, the nonlinear index of CTB = 66 dB, CSO = 64 dB, in the case of 108dBV output indicators; CTB = 58 dB, CSO = 62 dB ; two of the national standard were 54 dB, while building a network design is 55 dB, we can come to stack:


Can draw better than the national standard and design value.

This network are expected to bury the lines, network failure rate is very low, in the repair and failure to accept the telegraph, the main trunk and light stations and other equipment failures accounted for 5% of users are from the malfunction of other homes, including The kangaroo on the market amplifier and low-quality splitter installed, the user box, as well as informal decoration electrical wiring and so on.

Maintenance in peacetime, the month of the engine room of the optical signal and output level for testing and sampling some of the user whether the branch level and the design of consistent problems solved in time.

2. 2 pre-buried old line maintenance

This line have been pre-buried 8 to 10 years, when not building the engine room of network construction, optical receiver box to set the transfer in the ground, the latter by one to two dry place, and finally to put to boost the extension of the user. Transformation of the network, increasing the optical node and a number of PON equipment, so that the transfer will become more crowded box, you need to arrange a reasonable position of all equipment, cables neat appearance, good grounding of the equipment.

Transfer me to such a line from the unit to focus on distribution Lou Dong , Lou Dong splitter in the subscriber line is connected in series mode, each building is 3 units 6 layers, each 2, series 6 tap, tapping level of assurance than in the 70 dBV. Figure 2.


Figure 2 pre-district lines buried the old distribution network

Failure statistics in addition to 10% of the route failure, the 20% of F from the splitter head is bad and aging, the other for the failure of indoor users. Embedded by the user room for the tandem line, that is outside the line to the living room, living room out of a 5 user box parallel line to the master bedroom, master bedroom and another in the user box at a line out to second bedroom, For each room that received the normal line of digital signal to be in the living room and master bedroom of the user box office and put on a splitter. However, due to room conditions, not working properly, sometimes re-wiring damage to decoration, it is necessary to do the work with the user interpretation.

In such line maintenance, in addition to the monthly level to be tested, but also on the transfer of equipment for dust removal in the box to ensure the normal operation of the device.

2. 3 old cell line maintenance

Such area networking for more than 15 years, the main lines and distribution networks are set up open wire, steel wire to set up a rain on the box, optical receiver placed in the box, especially in respect of each house of the distribution network on the roof, cascading branches, and is - 5 lines allocated to each unit, each unit of branch lines in the household of the balcony edge, wind and sun, the line aging more serious. Transformation during the two-way network, increasing the number of optical node, set the pole side of a ground transfer boxes, workstations, and an amplifier on the light box, so that the maintenance of normal rod is no longer to climb the roof line Some of the original - 5 line switch - 7 lines focus on distribution, but because households are not at home and other factors, the user can transform the branch distribution lines, only to maintain the same. Figure 3 shows a typical layer of a block 6, 3 units, each two of Lou Dong After transformation, the distribution network, each unit of 6 to 8 splitter.


Figure 3, the plot full of open wire distribution network Maintenance of such a plot

up more than tedious plot described above, because the older residential housing, most of the elderly and the native population for some rental, some unoccupied space where, in line transformation, the line can only be modified to the roof. For each layer from the roof down to the line tap can not be modified, some leading cable off the aging line cards, the line seems very neat, so usually have to step up inspections, if found to have no regular home line and have tenants in a timely manner sort out. In addition, the roof splitter measures to make rain. When installing the set-top box, for some elderly people to teach the patient to operate. In the analog signal does not shut down the place, I believe that the installation set-top box, do not plug the analog signal, so as not to cause users of digital and analog signals of confusion.

2. 4 shelter farmers line maintenance

Areas where the author developed coastal areas, residents are more affluent, the overall conversion, such housing because of its multi-room, set-top boxes most of the four above, and some even up to several dozens, for the user, * several thousand dollars purchased set-top boxes, if the line is not good, look bad television, and their views will be very, home lines are former electrician himself or a television lines installed by the separation of the case, so the line quality is difference, we guarantee into the household level in more than 72 dB V under the premise of each set-top box only to straighten out the transmission line, redo F head, replacing the high-quality splitter, to ensure that each set-top box can be normal ratings.

3 Work Experience

Digital transmission network to do the maintenance work, each administrator to do:

Well aware of the trend line; on the operation of the device very much at home; phenomenon can accurately determine the fault; the situation with confidence to the user area; must be based on the idea of an emotional tie to do the work; spend more time learning about digital TV aspects of new theories, new technologies, to meet the social development.

X9C104S datasheetX9C104S suppliersX9C104S Price

All right reserved:icfull.com © 2010-2016 Certificate