Skanti DSC 9001, Technical Manual, Page: 89 / 178

Antenna
The antenna should be erected well in the clear and kept away as far as possible from electrical
equipment in order to minimize noise. Length: 7-30m.
Electrical installation such as cable braiding and instruments in the vicinity of the antenna should
be earthed effectively, and the instruments in question should be fitted with noise-interference
suppression devices, effective in the range 0.1 to 30 MHz.
The antenna feed-in should be coaxial cable, which should be as short as possible, especially in
the case of short antennas. If a long cable is used an impedance matching transformer should be
inserted in the antenna end of the feeder. For connector and cable specifications, see fig.19 at page
3-30.
Interconnection of Units
The units of the DSC 9000 are interconnected using a screened multiwire cable containing 5 twisted
pairs of wire between the Net connectors of each unit.
Important: Each unit contains a jumper which connects a 120 ohm resistor between terminals 2
and 3 of the net connectors, providing the necessary termination impedance for the serial data bus
of the net. The jumper must be removed if the unit is not located at the end of the chain.
See fig. 20 at page 3-31
The DU 9000-end of the cable is prepared by soldering a 9-pole D-Sub connector at the as
described in fig.21 at page 3-32. Assure that the twisted wires are correctly paired.
Where the mounting bracket is used, the DCU 9000-end of the cable is connected to the terminal
strip of the bracket, see fig.22 at page 3-33. Otherwise a 9-pole D-sub connector is used at this end
as well.
Prepared 5x2x0.25mmSq screened cable with 9-pole D-sub connector at each end may be obtained
from Skanti in 3m and 10m lengths:
3m: Part number 106 803 61
10m: Part number 106 803 51
Up to 5 control units may be connected to the DU 9000. The units must be chain connected.
Table 1 below shows the maximum permissible cable lengths for different numbers of control units,
using the cable type specified in fig.21 at page 3-32.
Number of
Control Units Maximum
cable length
1 180m
2 100m
3 75m
4 58m
5 47m
Table 1
DESCRIPTION INSTALLATION
DSC 9000 TECHNICAL MANUAL 3-5