L-3's Constant Efficiency Amplifier (CEA) IOT using a multi-stage depressed collector (MSDC) was a hit at NAB this year. While several manufacturers were showing MSDC IOTs for high power UHF transmitters, the L-3 CEA attracted attention due to its oil-cooled collector and increased efficiency due to a greater number of collectors. The CEA 130 IOT uses Poly Alpha Olefin oil for cooling and requires about one half the power of a conventional IOT for the same power output. The tube has been tested at output powers up to 30 kW. Efficiency is best at higher power.
The first transmitter equipped with the L-3 CEA IOT began broadcasting April 28, 2003 at WDSE in Duluth, Minn. and has been in operation for two months. Rex Greenwell, director of engineering and operations at WDSE Public Television commented on his experience with the tube, "The migration to broadcasting digital signals over UHF channels has required a great deal of power, consuming lots of electricity and increasing the cost of operation. The CEA 130 can significantly reduce those energy costs. It's really a revolutionary product. L-3's new CEA 130 technology promises to offer considerable energy savings over the life of the transmitter, and the potential savings we can obtain in energy costs may pay for the transmitter over its lifetime."
The CEA 130 is currently on the air at three stations: WDSE (described above), KVIE, Sacramento, Calif. and WNED, Buffalo, NY. All stations are using the Thales Paragon transmitter.
More information is available on the L-3 Electron Devices and Thales Broadcast and Multimedia web sites.
