SPG - Sync Pulse Generator

Master Clock/SPG 

Commercial broadcast systems have many individual sources and destinations, those generate audio  and video signal. In such multi sources/destinations environment every individual device gives outputs in an asynchronous way. This may result jerked or ambiguous frame in raster. After the generation of the video signal it needs a reference (path) to flow. If the signal finds no path the video signal may give information to the TV receiver other than the desired one. In multi sources destination environment it is desired for all signals to be synchronous with each other. For that purpose master clock or SPG (synch pulse generator) is used. It provides reference signal to all of the station equipments. It also generates the time code. For sooth and repayable flow the reference signal (black burst signal, colour burst signal) is provided. With respect to this signal the base-band signal flows to its desired destination without being disturbed. SPG section does that every thing. The master clock portion actually provides the TC (time code) for making all the equipment synchronized. This time code is generated by the satellite. A GPS (global positioning system) antenna receives the reference signal and the master clock portion generates the time code scanning the receiving signal. This time code is thrown to the GPS clock, VTRs. Server system etc.



 Figure : Time code and reference signal system block

There are  many professional SPG of various brand in broadcast market. Among those 5600MSC and 5601MSC of Evertz brand is popular.

         Figure: Evertz 5600MSC and 5601MSC SPG

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