Videotec sm328a, Operating Instructions Manual, Page: 41 / 344

7.3 Decoding the receivers
The receivers need to be decoded when telemetry communications are carried out via the matrix. Since a
composite installation has more than one matrix, each one has to know the ID number of any receiver
connected to each video input.
Any necessary decoding of the receiver number is carried out by the matrix and not by the keyboards:
proceed to assign the receivers in menu
2.1.7 Setup system/Video and installation/Assign
receivers for each matrix.
For each video input indicate the number of the receiver connected to it. If no receiver is connected insert
0 (zero).
7.4 Connection cables between matrixes
7.4.1 Communication cables
Use the telephone cables and RJjack boxes supplied:
RJjack1 RJjack2 RJjack3 RJjackN
White White White White
Yellow Yellow Yellow Yellow
Use only the white and yellow terminals in each box: connect white to white and yellow to yellow.
The matrixes are connected by an RS485 line with max. length 1200m. The two ends of the line (RJjack1
and RJjack
N ) should be terminated and the length of the stubs (from the main line) should not exceed two
metres.
To make the connection the AUXA connector on the back of the matrix should always be used.
7.4.2 Video cables
The video signal can be carried up to a max of 300m without distortion, using an RG58 cable. For longer
distances use transmitter/receiver couples with twisted pair.
•
7. Appendix 2: composite installations Page 37/66 MNVCSM328A_1511_EN