4.2.2 Connect Dual Coaxial Cable (75 ohm) to G.703 Network
The Model 1088/K is also equipped with dual female BNCs (TX
and RX) for connection to a 75 ohm dual coax G.703 network inter-
face. If your G.703/G.704 network terminates via dual coaxial cable,
use the diagram below to make the proper connections. The connec-
tor pinout and signals are shown in Figure 7, below.
NOTE: The outer conductor of the coax cables are isolated
from system earth ground.
4.3 CONNECT TWISTED PAIR DSL INTERFACE
The Model 1088/K supports communication between two DTE
devices at distances to 5 miles (8 km) over 24 AWG (.5mm) twisted
pair wire. Two things are essential:
1. These units operate as a pair. Both units at the end of the
twisted pair DSL span must be set for the same DTE rate.
2. To function properly, the Model 1088 needs one
twisted pair of metallic wire. This twisted pair must be
unconditioned, dry, metallic wire, between 19 (.9mm) and 26
AWG (.4mm) (the higher number gauges will limit distance).
Standard dial-up telephone circuits, or leased circuits that run
through signal equalization equipment, or standard, flat modu-
lar telephone type cable, are
not acceptable.
The RJ-45 connector on the Model 1088’s twisted pair interface is
polarity insensitive and is wired for a two-wire interface. The signal/pin
relationships are shown in Figure 8.
15
4.4 POWER CONNECTION
Universal AC Power (100-240VAC)
The Model 1088 uses a 5VDC, 2A universal input 100-240VAC,
power supply (center pin is +5V). The universal input power supply
has a male IEC-320 power entry connector. This power supply con-
nects to the Model 1088 by means of a barrel jack on the rear panel.
Many international power cords are available for the universal power
supply (Please refer to Appendix B for country-specific power cords.
The Model 1088 powers up as soon as it is plugged into an AC
outlet--there is no power switch.
120 VAC Power (US)
The 100-132 VAC adapter supplied with the U.S. version of the
Model 1088 is a wall mount type and may be plugged into any
approved 120 VAC wall jack.
230 VAC Power (International)
The 230 VAC adapter supplied with the International version of the
Model 1088 is a wall mount type and may be plugged into any
approved 230 VAC wall jack.
DC Power
The 36-60 VDC DC to DC adapter supplied with the DC version of
the Model 1088 plugs in a DC source (nominal 48VDC) and plugs into
the barrel power supply jack on the rear of the 1088/K. Please refer to
Figure 9 to make the proper connection.
16
Figure 8. Model 1088 twisted pair line interface.
1 (N/C)
2 (N/C)
3 (N/C)
4 (2-Wire TIP)
5 (2-Wire RING)
6 (N/C)
7 (N/C)
8 (N/C)
1
2
3
4
5
6
7
8
TX
(Data
TO
G.703/G.704
Network)
RX
(Data
FROM
G.703/G.704
Network)
Network
Figure 7: 75 Ohm Dual Coaxial G.703 Interface
