Black Box NTU-1 - Manual (Page 2)

2 of 3 9/19/2007
#11512 724-746-5500 blackbox.com
FEATURES
• Point-to-point or point-to-multipoint
configuration.
• Up to 18,000 feet (5500 meters)
operating distance.
• Easy configuration—everything you
need is on the rear panel.
• Uses standard RJ-45 jacks on all
interfaces.
• Operates automatically.
• For wallmount or desktop use.
• Power supply is included.
The NTU-1 in typical applications.
OVERVIEW
ISDN service requires an NT1 to connect the terminal
adapter to the ISDN line. If your terminal adapter doesn’t
have a built-in NT1, the NTU-1 is your affordable choice.
The NTU-1 converts the 2-wire echo-canceled 2B1Q code
from the central office to a Customer Premise 4-wire alternate
space inversion code. It supports both point-to-point and
point-to-multipoint configuration. All options and connec-
tions are accessible on the rear panel, and the NTU-1 comes
with surge protection. Also, all interfaces have standard RJ-45
jacks.
Power Information:
Wallmount Transformer—
The NTU-1 is normally powered from the wallmount
transformer. The transformer and the NTU-1 power-supply
circuitry provide 5 watts for up to two terminal devices
connected to the S/T interface. Connect the transformer’s
barrel connector to the Power jack on the rear panel. Plug
the transformer into a standard 120-VAC wall socket.
Signal Power—
The NTU-1 routes local and remote power to the signal
leads of the S or T interface. For phantom powering
applications, S/T interface connector pins 4 and 5 (Transmit)
are the negative power leads, and pins 3 and 6 (Receive) are
the positive power leads.
Remote Power—
The NTU-1 can receive backup power over the U interface
connector. The input must be a minimum of 48 VDC and
5 watts. Both local and backup power is routed to the S/T
interface connectors to power the associated terminal
equipment. Pins 7 and 8 on the U interface provide remote
power to both S/T jacks and the NTU-1.
S/T Interface
(100 ohms IN)
Multipoint S/T
Interface
(100 ohms IN)
Multipoint
S/T Interface
ISDN U Interface
from Telco
(100 ohms IN)
ISDN U Interface
from Telco
(100 ohms IN)
ISDN U Interface
from Telco
(100 ohms IN)
TE
TE
TE
TE
TE
NTU-1
(IS200A-R2)
NTU-1
(IS200A-R2)
NTU-1
(IS200A-R2)
100 ohms IN on either one of the units,
and OUT on the other
100 ohms IN on unit with
longest cable
100 ohms IN on unit with
longest cable
Up to 1 km Up to 1 km
Passive Bus
Connection Point-to-point
connection