AM Triplexer Overcomes Unique Challenges in Taiwan
LBA Technology has shipped a specially built advanced technology Medium Wave Triplexer system to the Broadcasting Corporation of China for installation in Taiwan. This is the second major multiplexer system LBA has furnished to BCC.
The BCC site created a number of challenges. Site limitations required that the triplexer operate into an electrically short tower in the middle of a lake, with only a small platform area 30 feet above the water available for the tower base and the triplexing equipment.
LBA senior engineer Marvin Brewer simulated the electrical requirements by NEC modeling and specified the installation of an LBA Technology Q-Cage™ broadbanding kit on the tower to improve matching impedances. He then designed a triplexer system in three independent ATU – RF filter combinations. These weatherproof cabinets were designed to cluster around the tower base, while permitting adequate maintenance access. The LBA Technology shop experts fabricated, adjusted, and tested the entire system.
As its name implies, a triplexer allows the multiplexing of three medium wave AM transmitters into a single antenna. Triplexers include an antenna tuning unit and rejection filter sections for each frequency to allow the passing of the desired frequencies while rejecting the undesired frequencies. The triplexer system for BCC was designed for 531kHz, 648kHz and 963kHz, and 10,000 watts power at 125% modulation for each frequency.
The triplexer system was delivered through international transmitter manufacturer Broadcast Electronics in Quincy , IL. LBA has partnered with BE on projects in the United States, the Middle East, Far East Asia, Afghanistan, Iraq, and the United Kingdom.
LBA Technology custom engineers multiplexers to enable broadcasters to feed multiple transmitters to common antenna systems as a cost effective way to minimize the physical plant requirements of AM broadcast stations. With almost 50 years of experience, LBA provides a wide variety of AM broadcast antenna solutions for all power levels, worldwide.
