The PCO-818/SA is the change-over for an analog system. The modules included in this configuration are; 818-OP/BB, Analog Black burst 818-OP/SC, Analog Subcarrier 818-OP/PL, Analog Sync As your system grows and new technology arrives, the PCO-818 stands ready to grow with you. The PCO-818 is engineered to provide complete syncsystem reliability in a compact, easy to use, and economical package. It's advanced modular design provides a level of flexibility never before available in an Automatic Changeover unit. When combined with it's sync generator companion, the SPG-812, the PCO-818 can offer the best performance and reliability available today. The basic function of the PCO-818 is to monitor an installation's primary sync generator and automatically switch to a backup generator in the event of a failure to the primary. It's modular design offers several advantages over traditional automatic changeover units. Monitor only the signals used by the system: no need to pay for monitoring capability that is not required by the system. Install only the modules you need now-add more later. Each module is matched to it's signal: this allows us to accurately monitor pulses of various amplitudes and widths. It also allows us to mix analog and digital signal monitoring in the same chassis! Since the PCO-818 and the SPG-812 Sync Generator share a common chassis, modules may be interchanged between units. For example, an television station may use a single SPG-812 generator with a backup blackburst generator installed in the changeover chassis! In addition, the PCO-818 is designed such that AC mains failure will not erase the memory of it's last generator selection. Dual-coil latching relays provide a reliable signal path even if power is lost to the PCO-818. Meanwhile, its power supply features a "universal" voltage input range of 85VAC to 260VAC. In extreme conditions, the PCO-818 would be the last unit to shut down in the event of an AC mains failure. Bi-color LEDs provide instant status indication for each signal in your system. If a particular signal is not in use, the LED can be easily de-selected (dark) rather than produce a false failure (red) indication. A "Manual/Automatic" switch allows the user to override the automatic changeover function and select either generator in the system.