As the Lasher Turns

Written by: Slack Span , Lookinatmyfeet , Princess and Wood Pecker

The Cable Television Industry has become the pioneer in Technology. Cable Television Providers have forged new grounds and answered the calls of both their subscribers and stockholders. Utilizing the latest resources, they have met the challenges of their customers by providing reliable, low cost service, with increasing quality. Thanks to the quantum leaps in technology they have been able to maintain, and even increase the profit margins, thus increasing the returns to their stockholders. There appears to be new technology emerging everyday for the MSO’s (Multiple Systems Operator) to develop into their cable systems.

Engineers are constantly striving to integrate new technologies with already existing infrastructures. Deciphering and organizing the information required to achieve seamless integration can prove to be a logistical nightmare. The countless variables such as existing coax cables, fiber optic cables, their footages and their specific fiber counts, can prove challenging even to the most season veterans. Should the need arise for a new plant to be constructed a new set of challenges arise, increasing the task and difficulty exponentially. After engineers have developed a strategy for implementing these cable upgrades, rebuilds and plant extensions it is then the responsibility of the accounting department to align the financing for the multi-million dollar projects. When executing the strategy and successful completion of the project there are many problems that may be unforeseen and may rise during the build time causing setbacks which may result in loss profit and delayed completion times. Timely delivery of materials is key to maintaining the desired profit margins. Quality skilled labor is vital to the successful completion of the projects.

Rather than perform these tasks in house most MSO’s opt to hire a Prime Contractor to handle the difficult task of completing the construction project. A quality Prime Contractor has in place a book of businesses not limited to but including sub-contractors and suppliers. The construction crews will take reels of cable, strand and conduit out daily and install lines in the air or in the ground. Aerial construction crews will start off by installing the strand to the poles and anchoring them. This is known as a support cable. The cable will then be pulled out on the strand in rollers. When the construction crew nears the end of the run they will lash the cables to the strand and leave the tails in their specific locations.

The construction crew could be lashing an assortment of cable for example, Coax, Twisted pair and Fiber being the three most popular. All construction is done to specific specifications determined by the Power Companies and the MSO’S. Underground construction is sometimes needed where the pole lines do not exist. After the cable placement is completed it is turned over to “cable splicers” or "coax splicers".

The third and final phase CableTV plant construction consists of splicing, plant activation, forward and reverse sweep and CATV plant certification. After all the coaxial and fiber optic cable has been installed, a team of splicers utilizing system design maps will splice the cable together and install all the active and passive equipment. (I.E. fiber / coax nodes, amps, power supplies, line splitters and aps.) During this time, some design changes may have to made and submitted back to the engineering dept for redesign. The fiber optic splicers will splice the fiber optic cable together and install the splice enclosures. They will also splice the fiber optic jumpers or pigtails at the node locations, which will allow the fiber optic cable to be connected to the nodes. Once all the fiber has been spliced an optical time domain reflectometer (O.T.D.R) will be used to check the entire length of the fiber for loss and splice integrity.

Once all the splicing is complete the next process is plant activation. Activation consists of applying and routing power to correct nodes, amplifiers and line extenders. The routing is accomplished by using the system design maps and by adding or pulling shunts and sending power to the correct location. Also during activation voltage readings will be taken to ensure proper levels and to make sure no shorts or opens exist and to confirm that power is entering the active at the desired port. Depending on the system, a “rough balance” may also be accomplished during activation. This involves setting the levels in the actives to a specified tolerance of the design levels.

Next the sweep techs are sent in to check the integrity of the coaxial portion of the cable system. Basically, sweeping is the process of injecting a signal across the entire frequency spectrum of the cable plant an the headend and then using a sweep meter to balance the actives to design specifications and to measure the frequency response throughout the entire system. The sweep technicians will start at the node and then move to next active in line and continue until they reach the end of line. In addition to checking and documenting frequency response, sweepers will also check system voltage, operating voltages of the actives and document any design variations. Most of the systems will require the sweep technician to repair any problem they may find.

After the sweep and balance is complete the cable system is certified to ensure the plant meets F.C.C. standards. Some of the tests include: In channel response, cross modulation (XMOD), carrier to noise (C/N), composite second order beats (CSO),composite triple beat (CTB) and hum. Some systems are also including modulation error rate (MER) and bit error rate (BER) documantation as well.

After everything has been spliced and tested, the finished product is turned over to Network operations and the Sales Team. The orchestrating of all of these crafts will ultimately determine the success of the MSO.

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