Operational Description

Operational Description:
The EC-704MP digital transmitter system is an up to 350W average power (when using ATSC 1.0 8VSB
modulation), 300W average power (when using ATSC 3.0 COFDM modulation) that consists of a
Hitachi Kokusai Electric Comark (HKCM) Exact V2 digital exciter, Hitachi Kokusai Electric Linear (HKL)
CM-8001 Drive controller, one (1) HKL GV40010 Amplifier, a passive hybrid combining system, an HKL
40243 Low pass filter, and a Com-Tech FC6D60C 6 Pole Mask Filter (or equivalent or more stringent
filter). The final stage of amplification operates at 50VDC and 20A at full power. This system is used to
provide an ATSC 1.0 (8VSB) or ATSC 3.0 (COFDM) modulated signal over the UHF channels 14 through
36 in a manner consistent with FCC Part 74. Output power from, maximum power to 0W depending on
the modulation standard, is controlled via attenuator circuitry in the CM-8001 Drive controller.