Grass Valley 8960DEC - Manual (Page 45)

8960DEC—Instruction Manual 45
Functional Description
Functional Description
Refer to the block diagram in Figure 22 while reading the following func-
tional description.
Figure 22. 8960DEC Block Diagram
Analog Input and A/D Conversion
The analog video signal is connected to the high impedance loop-through
input. In the analog section the DC black level is automatically restored to
produce standard D1 output blanking levels. The overall video-gain
adjustment gives a ±3 dB range to compensate for standard input video
levels. Before the 12-bit resolution A/D converter, the signal is lowpass fil-
tered to avoid anti-aliasing artifacts.
The input serves as the timing reference for the digital decoding process
and is highly tolerant to low quality and noisy signals. The noise level can
vary from as low as 14 dB S/N (white noise) to noise spikes measuring as
high as 1 V p-p (satellite narrow spike noise).
+12V
-5V
Module Slot ID
+5V
Fault Reporting
Local User
Interface
Intra-frame Control Interface
NTSC/
PAL
Input 10 10 10
525 Reference
Timing 4X 4:2:2 SDI
625 Reference
Optional Submodule *
* The main decoder module automatically recognizes the attachment of the frame synchronizer submodule.
AES Delay Data
Microcontroller
On-board
Switching Mode
Power Supply
module
Analog
Input
Processing
12-bit
A/D
Converter
Frame Delay/
Synchronizer
H lock to
External Video
EDH Insert
Parallel/Serial
Converter
Output Driver
3-line
Adaptive
Comb
Decoder
Data Switch
0543_01r1