TABLE OF CONTENTS James Michener
The function and design of sync generators have changed over the years to respond to new requirements and to simplify facility wiring. Sync generators are typically employed in one of three different applications: as master sync generators, as slave sync generators, or as source-oriented sync generators.
The master sync generator is just that, the master clock for an entire video facility. This generator determines the absolute frequency stability of the facility and should therefore be very stable and absolutely reliable. Any problems with the master clock will ripple throughout the facility. Often two sync generators and an automatic changeover switch are employed for redundancy. The master generator typically uses an atomic-based oscillator as the master clock to precisely determine subcarrier frequency. This generator can generate standard television pulses or any single-line reference pulses. The pulses and reference signals are usually distributed to other source equipment.
Many pieces of source equipment employ an internal sync generator. This provides regeneration of all the required television pulses at the proper time for internal use and permits the output video time to be set arbitrarily with respect to the reference to simplify system input timing requirements.
A slave sync generator is like a master in that it derives standard television pulses and reference signals that can be distributed to source equipment; however, this generator is usually locked (slaved) to a master. The slave can be locked precisely to the master but typically provides outputs...
