Comtech EF Data SDR-54A - Manual (Page 50)

SDR-54A Satellite Demodulator Revision 4
Reed-Solomon Option MN/SDR54A.IOM
6.4 Reed-Solomon Codec
The design implements R-S decoding by utilizing the Advanced Hardware P/N
AHA4011B chip set. Refer to Table 6-1 for R-S codes.
Table 6-1. R-S Codes
Service Data Rate
(kbit/s)
R-S Code
(n, k, t)
Closed Network 4.8 to 4375 kbps 225, 205, 10
Note: Reed-Solomon concatenated decoding is compatible with the Comtech EF Data
SDM-300 Series or SDM-8000 modems.
6.5 Reed-Solomon Installation
Install the Reed-Solomon card as follows:
1. Remove the six 6-32 pan head screws which secure the cover to the chassis.
Note: The cover and chassis are held together by flange tabs located on the top
and bottom surfaces.
2. Remove the cover from the chassis as follows:
a. Two extraction slots near the front of the unit are located on the top surface.
b. Separate the chassis and cover by placing a screw driver into the extraction
slots and twisting.
Note: To remove the chassis from the cover, gently pry the chassis and cover
away from each other.
CAUTION
Use Electrostatic Discharge (ESD) precautionary procedures when
touching, removing, or inserting PCBs.
3. Gently insert the Reed-Solomon card into the socket, with the card-edge (the side
with the silver strips and ‘RX Reed-Solomon’) facing downward.
4. Carefully apply a slight amount of pressure downward on the top of the card, until
it snaps into position in the connector socket’s retaining clips.
Note: The correct position of a properly installed AS/6285 Reed-Solomon card is
standing nearly upright, tilting at a slight angle, as shown in Figure 6-4.
6–4