The new system can transmit more channels without altering the configuration of the headend or transmitter. This is made possible by substituting a transmitter channelized by one providing broadband frequency agility within the band.

This system is giving digital television coverage in the region around the city of Reynosa, in Mexico, near the Texas border.

This project was implemented by a team of experienced technicians and engineers from RBA CATV with the technical support of the Cable AML team.Once the transmitter installation was completed and commissioned, a detailed coverage verification and signal analysis program was developed by the technical team of RBA CATV. RBA Manager, Jose Pablo Fernandez, is “totally satisfied with the Cable AML equipment and support during the installation of the new transmitter,” and in view of the good performance of the system he is in the process of extending
coverage to nearby cities using links and repeaters

The digital TV signals originate in the existing digital MMDS system in the country’s capital, Dakar. A microwave link using broadband microwave radios from Cable AML is used to transport the digital signal 14 Kms to a repeater point at Kissane. From Kissane it is relayed to two new MMDS sites, one at Thies 10 Kms away and the other at Mbour, 28 Kms away. A broadband MMDS transmitter then re-transmits the signal for local subscribers at the two cities.

The installation and commissioning of the system has been under the technical direction of David Vine, who has previous experience with both DTT, MMDS and digital cable systems.Mr. Vine said,“Duplicating the Dakar headend in Thies and Mbour would have been cost-prohibitive, With Cable AML’s equipment, we are able to provide excellent signal quality to residents in these two remote communities.”

The new transmitter operates in the 2.2 to 2.3 GHz band, which has been recently made available for MMDS service in several countries.

The digital MMDS system operates under harsh environmental conditions, specially low temperatures, as can be appreciated by the attached photos. Cable AML has also supplied repeaters to extend the coverage of the transmitter to shadow areas.According to Alexander Fedukovich, Senior Engineer at C-Gates, and the person responsible for the installation, commissioning and operation of the system, “The 500W transmitter in Vilnius has been working from day one providing excellent quality and requiring no maintenance whatsoever. We really appreciate the ease of installation and the outstanding reliability of this transmitter.”

The upgrade implemented by Rios & Cia included the design of two headends for HD signals encoded in MPEG-4 format as well as the simultaneous upgrade to digital and frequency migration of two redundant PTP links feeding a redundant broadband MMDS transmitter.

Following concurrent transmission of analog and digital signals during a test period, Rios & Cia has recently completed upgrading the remote receive stations prior to commissioning of the system.According to Ricardo Rios, President of Rios & Cia, “The initial design, implementation and successful completion of this project has been facilitated greatly by the cooperation and assistance of Cable AML in all phases of the project.”

Phase I of the system upgrade included the implementation of a cable-compatible MPEG2 digital headend, integrated with a new CAS (Conditional Access System) and the replacement of the old channelized transmitter with a new solid-state dual-redundant broadband transmitter.

Phase II was focused on updating subscriber installations and installing repeaters to improve signal coverage in certain areas.

Given the much higher capacity of the digital system, the conversion has made it possible for Cable Onda to improve significantly the number of TV programs available to its subscribers.

According to Karlos Brown, CTO of Cable Onda, “the conversion was successfully implemented without interrupting service to any of our subscribers. We are very happy with Cable AML’s continued support for our expansions and upgrades to our wireless systems.”

The expansion plan included upgrading the main Zacatecas transmitter to 500 Watts to cover the capital city and strategically located repeaters nearby.A new 250 Watt repeater in Santa Monica has been installed to provide coverage in the Western part of the state. A new transmitter was installed in the city of Monte Escobedo to provide coverage to the entire urban area. Similarly, a new 250 Watt transmitter has been installed in Valparaiso at the confluence of Durango, Zacatecas, Jalisco and Nayarit, where two repeaters (one at Lobatos and one at San Mateo) serve adjacent communities and the surrounding semi-rural areas.With the latest expansion, TV ZAC provides coverage in all the main cities and towns in the state of Zacatecas. Says Lic. Francisco Aguirre, general manager of TV ZAC: “The expansion of the system was conducted quickly and efficiently, mainly due to the good performance of the Cable AML equipment and ease of installation.

Careful planning and execution of the switch over minimized disruption to any of the more than 10,000 system subscribers. The digital performance of the system, including the repeaters, was tested by transmitting a single 6 MHz digital carrier with the analog signals.The headend and the CAS were installed and commissioned prior to selecting a switchover date. Several thousand digital Set Top Boxes were distributed to customers. System Manager Anne AMES set up four outdoor PC stations, an outdoor conainer store and an overhead tarp. Twelve assistants answered queries and assisted customers with channel package selection. Demand for the improved service caused customers to wait in line as long as 2 hours but the average wait was only 30 minutes. The digital take-up rate has been huge. According to HITRON’s Chief Operating Officer, Lindsay Jorgensen, “Cable AML’s system was crucial to the successful deployment of a state-of-the-art digital system that will enable our company to be at the forefront of high quality video service providers in Papua New Guinea for years to come.”

Multivision’s most recent purchase of Cable AML transmitters was part of an on-going program to install new transmitters as well as upgrade some of the 31 transmitters installed by Cable AML in 2003. The upgrades were designed to boost the output power so as to increase the coverage area.

“The ability to upgrade transmitters in the field is a result of Cable AML’s deliberate adoption of the modular design concept, which is based on common blocks of discrete components to ensure not only upgradability but also long life and ease of service and repair,” said Dr. Francisco Bernues, President of Cable AML.

Multivision serves markets that are often separated by hundreds or thousands of kilometers in places like Acapulco, Culiacan, Durango, Hermosillo and Mazatlan.The distance alone can make it difficult to coordinate shipping and installation. Cable AML relied on its years of experience delivering products and services worldwide to meet the challenge. “We provided the customer with fast delivery, customized logistics and complete solutions packages including antennas and accessories shipped, prepackaged to each of the 12 different destinations, plus 24/7 support in Spanish,” Dr. Bernues said.

The upgrade consisted of a digital Headend feeding a broadband 1000 Watt transmitter capable of reaching over 40 kilometers with a load of 10 digital carriers (60 to 80 TV programs) modulated in 64-QAM.

According to Ing. Angel Vacacela, “The switch-over from analog to digital went very well thanks to Cable AML’s assistance in identifying possible problems and issues ahead of time and preparing a comprehensive plan which included training at their facilities in Los Angeles.”