4-3
Servicing Precautions
Powering Down
WARNING
Unless specifically directed to do otherwise by a maintenance procedure,
turn power off before removing or repairing any circuit module or assembly
in this system.
Before working on any power supply assembly, turn off the power and
disconnect the power cord from the AC power source.
CAUTION
When power to the Signal Processor Frame is turned off, current switcher state
data (e.g., selected video/key sources, key memory, etc.), stored in volatile
Dynamic Random Access Memory (DRAM), is lost. E-MEM data will be retained
since it is stored in battery-backed Static Random Access Memory (SRAM), which
can retain data for several years without power.
Removing any of the mezzanine boards from the Control Processor Modules will
result in complete data loss from the battery-backed SRAM on the mezzanine
boards removed. This occurs because the batteries supplying power to these
boards are located on the main Control Processor Modules.
Summary of Contents for Grass Valley 4000
Page 3: ...iii Tektronix Grass Valley Products P O Box 1114 Grass Valley CA 95945 916 478 3800 ...
Page 4: ...iv Tektronix Grass Valley Products P O Box 1114 Grass Valley CA 95945 916 478 3800 ...
Page 34: ...1 20 Section 1 System Overview ...
Page 138: ...2 104 Section 2 Installation ...
Page 196: ...3 58 Section 3 Functional Description ...
Page 286: ...Index 6 Index ...
