The Calrad 40-214 Digital ATSC RF modulator provides a simple method of transmitting HDMI 1080P video to multiple TV displays with built-in ATSC RF tuners over standard RG59\RG6 coax and in some configurations signals can be delivered over Cat5e, Cat6 cabling, using specific RF adapters. Systems can be designed with 1 channel or up to 56 different channels. Multiple 40-214 digital ATSC modulators can be easily connected together in a series configuration to build a simple video matrix system, the system can easily be expanded to meet your customers needs at a very affordable cost. Each ATSC digital modulator can be configured to its own RF output channel-frequency. RF signals can easily be connected to standard digital splitters and amplifiers to send multiple HDTV channels to many displays in various locations. The RF TV channels can easily be changed on each TV display to the appropriate video source delivered by each ATSC RF modulator. A front panel digital display provides a simple configuration of RF output channels-frequency and settings to setup the source name. This name is accessible by selecting (info) from any TV to display the RF channels source name on TV screen. The hardware of the 40-214 has Non volatile memory to secure all data and settings if power is lost. Diagram 1A below shows a typical installation using 4 pieces of the 40-214 connected to 4 independent direct TV receivers, each 40-214 is wired in series and connected to a 6 way digital splitter, each RF cable is then wired to each TV display for independent channel viewing with access to channels 20, 22, 24, 26. A 20db attenuator is included for short cable runs that may provide to much signal for some TV ATSC tuners causing intermittent video or no video signal. For all technical questions related to system design and signal loss calculations.