User's Manual

Page 3–13
18 September 2007
SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
eNfusion™ HSD-128 High-speed Data Terminal
Access to the HSD Maintenance Utility Program is achieved by connecting an
RS-232, VT-100 terminal (PC or Laptop operating a terminal emulation program)
to the RS-232 Maintenance Port.
The HSD Maintenance port is available at the front of the HSD and at the rear
ARINC 600 connector. Connection on the front of the HSD is accessible via a
DB25S connector for local maintenance of the unit. Remote access is provided
for cases where local access is unavailable. For remote access, install an
accessible DB9S connector in the cabin area.
Note: The front panel and remote connections to the maintenance port cannot
be used simultaneously.
Refer to "Test and Fault Isolation" on page 4-1 for information on how to connect
and use the maintenance port—including, equipment requirements, connection
and cabling requirements, software loading instructions, and configuration
details.
(c) Antenna Subsystem RF Interface – Stand-Alone
Several external RF parameters (such as cable losses and antenna gain), that
must be delimited to ensure proper operation, dictate the HSD performance
requirements.
Table 3–3 defines these parameters and their expected values.
(d) WOW Pin Wiring – Stand-Alone
These Weight-On-Wheel (WOW) discretes are wired only if equivalent
information is not strapped as being available to the SDU on an ARINC 429 input
[for example, IRS or the Centralized Fault Display System (CFDS)].
WOW wiring, for the HSD, is optional for system operation as the HSD already
receives speed information for Doppler correction. However, if WOW wiring is
not wired, normal maintenance must be disabled when speed or Doppler
readings are greater than zero.
The WOW1 and WOW2 pins are either left open circuit or they are connected to
the airframe DC ground. The WOW Program Select (PGM) pin is either left open
circuit or is connected to the Forward Address Common. The three ground states,
defined for any pin are:
• OPN: Open circuit
Table 3–3. RF Parameters Definition
Parameter Min. Value (dB) Max. Value (dB)
Antenna Gain 8 17
Antenna—DLNA Loss 0.1 0.3
DLNA Gain 53 60
DLNA Noise Figure 1.5 1.8
DLNA—HSD (Rx) Loss 6 25
HSD—Antenna (Tx) Loss 1 2.5
DLNA Insertion Loss (Tx to
Antenna Port)
–0.8