
digital test system
Features
• Flash PROMs Allow New
Software Downloads via
Dial-up Connection — no
more PROM replacement
• Expandable Architecture —
Built-in expansion slots
• Advanced User Interface
featuring a 4-line, 160
Character Backlit
Supertwist Display
• Speaker Output — Voice
conversation monitored
simultaneously in both
directions
• History file permits multiple
storage of measured events
D400/D450
Description
If you’ve been waiting for the perfect digital test set, then wait
no longer! The Wilcom D400 Digital Test System ushers in a
new era in transmission testing. By providing a complete set of
T1 Test functions today while looking ahead to your testing
needs of tomorrow the D400 removes one major drawback
found in other test sets — obsolescence.
Rest easy knowing you can purchase only those test functions
that are required immediately. Then as your testing needs grow,
simply purchase the option cards and software packages that
meet your new demands. Installation is easy, performed by you
or through our factory. To make installation of option software
as simple as possible, the D400 includes Flash PROMS. Using
Flash PROMS allows downloading of new system software by
dial-up modem connection. Therefore, physically changing
the PROMS is no longer a concern. In a world of ever changing
technology, the D400 is definitely a safe investment.
The D400 Digital Test System is designed with expansion in
mind. Its rugged chassis can accommodate a wide selection of
option cards (e.g. BERT testing, DS3 Drop & Insert, DTMF/
MF signaling, DDS & Factional T1, FDL Access, SLC-96
Derived Data Link access) and two processor enhancements
(e.g. memory expansion, internal dial-up modem). Back panel
connection plates provide the capability to add any type of
future connector — including 75 Ω coaxial, RS-232C, and
fiber optic. The 75 watt power supply has enough muscle to
support all currently available and future option cards, and the
Intel 80188-based processor has memory and capacity to spare.
The D400 Digital Test System is available in two versions: a
bench test set version, the D400 with five expansion slots and
a field test set version, the D450 with two expansion slots. Both
base units are complete in-service T1 test sets. Their fullduplex drop and insert capabilities allow simultaneous channel
testing in both directions. The two channel tone synthesizers
and receivers provide noise and frequency measurements from
0 to 3990 Hz. Bit patterns can be sent and displayed in both
directions simultaneously. The A/B/C/D signaling bits of all 24
channels can be scanned and displayed on screen. Loop timing
and frame slip counting is performed. Plus all the performance
monitoring features are included so tariffed service requirements can be checked and verified. This makes the D400 and
D450 base units complete DS1 test sets unto themselves.
Several optional accessories are available, including the D555
Non-Intrusive Probe used for testing T1 anywhere on twisted
pair, a thermal printer, and a padded carrying case. Shipped with
every unit is a comprehensive manual and the D400 EZ Test
Index, a quick step-by-step guide to test setup.
Wilcom

Isolates loop timing problems and verifies
stratum 2 clock synchronization. Improperly
synchronized networks experience occasional
frame slips which cause momentary disruptions to channel data.
Description
Signaling Bits, Digits, Tones, Levels, Frequencies,
Alarms, any channel - all channels.
The Slip Counting feature allows the clock rates of
two T1 sources to be compared. Any differences
are counted and accumulated. This allows users to
determine if tariffed synchronization specifications
are being met. A simultaneous display of the T1
line frequency leaves no doubt as to the source of
trouble.
All 24 channels of signaling data can be displayed
simultaneously. Select the bits to be displayed in
both the East and West direction on two display
screens.
The D400 has a built-in tone synthesizer. Any tone
from 0 to 3990 Hz can be generated from +2.9 to
-60.0 dBm on all 24 voice channels. The receiver
section can measure the frequency and level of tones
over the same range.
Uses include: measuring loss, simulating
modem carrier tones, disabling echo
cancellers, responder tests.
In-Service testing of T1 or DLC, channel
by channel, card by card, bit by bit,
without service interruption.
Feature
In-Service
Channel Access
Sending and
Measuring Tones
A,B,C,D
Signaling Bit Scan
Slip Counting and
Line Frequency
The Basic D400 Digital Test System
Applications
This allows users to monitor active channels
and compare signaling states in either
direction. Provides immediate activity
assessment.
Monitoring of voice or test tones in either one or
both directions simultaneously is possible through
the volume-controlled speaker or through a
headset.
In addition to displaying frequency and level, the
built-in tone receiver measures PCM offset on any
channel.
In properly operating systems, PCM offset
should be in the range of ±10 binary units
for voice traffic. Excessive offset could
indicate a faulty codec that could interfere
with signal processing devices such as
echo cancellers.
Allows direct assessment of channels at the
user level.
Measurement of
PCM Offset
Monitoring of
Voice or Test Tones
Activates or deactivates loopback features of
Channel Service Units (CSUs) or Network Interface
Units (NI or Smart jacks). Intelligent repeaters and
CSUs can be looped back through entering user
programmable codes for fault isolation.
Fault isolation on a T1 line equipped with Smart
Repeaters can be individually looped back through
programmable codes.
Any user defined 8 bit code can be sent on any
channel of a T1 span using this feature. The
received channel can be displayed in a 1/0 code
format.
To perform single-ended, out-of-service
testing of a T1 circuit, it is usually necessary to loopback the far-end of a circuit.
Channel Service Units (CSUs) contain
built-in circuits that can detect a standard
code sent over the T1 link. The CSU
Loopback feature not only transmits the
proper codes, but indicates when the CSU
has attained loopback and reminds the user
to disable the loopback when testing is
complete.
This feature is useful for checking
loopback and maintenance codes on data
circuits, and in circuit identification.
CSU Loopback
NI Loopback
Smart Repeater
Loopback
Sending and Receiving
Channel Codes

Specifications for the D400 and D450
T1 Receiver
• 1.544 Mbps: ±130 pps
• Level range: ±3 V bipolar peak to peak
±75 mV
T1 Measurements
• T1 Line Frequency
• dBdsx
• dBm
• Vpp
• Frame Error Count
• BPV Count
• CRC-6 Error Count
• Slip Count
• Frame Error Rate
• BPV Rate
• CRC-6 Error Rate
• % Available Seconds
• % Errored Seconds
• % Error Free Seconds
• Available Seconds
• Errored Seconds
• Error Free Seconds
• Severely Errored Seconds
• Yellow Alarm
Channel Measurements
• Frequency range: 0 to 3990 Hz ±2 Hz
• Level range: +3.0 to -60.0 dBm
• Binary Coding: any 8-bit pattern
• PCM Offset: µ-255 law
• Signaling bits: 24 bit scan
Analog Input/Output
• 600 ohms, balanced, non-DC blocked +/-5%
T1 Source
• 1.544 Mbps ±5 ppm bipolar peak to peak
• AMI, B8ZS, BIT7 (bit 7 stuffing)
• SF, SF/CCIS, ESF, ESF/CCIS
• SLC Series 5, SLC 96
• Output Pulse ±3 volts bipolar peak to peak, -7.5 and
-15dB LBO
• Drop and Insert is fail-safe if AC power fails
Channel Synthesizer
• Frequency range: 0 to 3990 Hz, in 10 Hz steps
• Level range: +3.0 to –60.0 dBm, 0.1 dB steps
• Binary Coding: any 8-bit pattern
Status Indicators
T1 T3
• Frame Error (FRM) (FRM)
• Bipolar Violations (BPV) (BPV)
• CRC-6 Errors (CRC) (PAR)
• Yellow Alarm (ALM) (ALM)
• Loss of Signal (LOS) (LOS)
General
• Built-in Clock and Calendar
• Results Print Range: 1 min - 24 hrs.
• Results Reset Range: 1 min - 24 hrs.
• 3 factory-programmed set-ups
• 15 user-defined setups
• On-line HELP key
• 2 RS-232C ports configured from 300-9600 baud
• FDL access in/out rear panel 9-pin connector
Connectors
• T3: WECO Type 560A (440A compatible) jacks
• T1: WECO Type 310 or Bantam (miniature) jacks
• Analog: WECO Type 310 or Bantam jacks
• Headset: WECO Type 310 jacks
Environmental
• Operating Temperature Range: 0 - 40° C
• Relative Humidity: 0 - 90% non-condensing
• Storage Temperature: 0 - 70° C
Dimensions
D400 D450
• Width: 16.00 in (40.64 cm) 16.00 in (40.64cm)
• Height: 6.75 in (17.145 cm) 6.75 in (17.14cm)
• Length: 17.63 in (44.78 cm) 11.00 in (27.94cm)
• Weight: 22.84 lbs (10.36 kg) 14.91 lbs (6.76 kg)
Power Requirements
• 115 VAC, 50 - 60 Hz, 0.5 amp maximum
• Fuse : 1 amp slow blow
Standards
The D400 (where applicable) conforms to:
PUB 62411 ANSI T1.403-1989
PUB 54016 ANSI T1.503-1989
PUB 43801 ANSI T1.101-1987
CCITT G.821 ANSI T1.103-1987
TR-TSY-000008 ANSI T1.102-1987
ANSI T1.104-1988
ANSI T1.103a-1990

D400 OPTION CARDS:
Customize your D400 Digital Test System by
inserting the option cards listed below. Insert
one, two or all the cards into the D400 for
complete digital testing, and there will still be
room for future options ... making the D400 a
smart, long term investment.
D401 BERT OPTION
• QRSS
• 3 in 24
• All ones
• 1 in 8,
• Programmable, and more...
D402 SIGNALING OPTION
• Draw dialtone
• Dial out
• Receive digits and analyze
• MF, DTMF, dial pulse
D403 DS3 DROP & INSERT OPTION
• In-service DS3 testing of DACs IV
• M13 multiplexer
• Embedded DS1s and DS0s
D404 DDS & FRACTIONAL T1 OPTION
• Latching and alternating loopback
testing of DS0 and DS0 subrates
• Bit Error Rate Testing of DS0s
• MJU Control
• BERT of Fractional T1
• SRMU Testing (See insert for specifications)
D406 SLC 96 OPTION
• Emulates SLC 96 remote terminal
• Emulates central office terminal
• Provides ringing
• Tests individual channel cards
• In-service or out-of-service pre-cutover
• DDL Access
• Drop & Insert
• Modes I, II, III, and Series 5
• Full Channel Access.
D408 SLC 96 SIGNALING STATE
ANALYZER OPTION CARD
• DDL Analysis of Call Originate
• DDL Analysis of Call Disconnect
• DDL Analysis of Forward Disconnect
• DDL Analysis for C-Field Timing
• DDL Analysis for Test Configuration
• DDL Signaling Bit Timing and more...
Ordering Information
D400 DIGITAL TEST SYSTEM BASE UNIT PART NUMBER
Select one of the following:
310 Jacks, AC Powered 30400010
Bantam Jacks, AC Powered 30400020
310 Jacks, -48V DC Powered 30400030
Bantam Jacks, -48V DC Powered 30400040
D450 DIGITAL TEST SYSTEM (2 EXPANSION SLOTS)
Select one of the following:
310 Jacks, AC Powered 30450010
Bantam Jacks, AC Powered 30450020
310 Jacks, -48V DC Powered 30450030
Bantam Jacks, -48V DC Powered 30450040
D400 OPTION CARDS
D401 Bit Error Rate Test (BERT) 30401010
D402 MF/DTMF/DP Signaling 30402010
D403 DS3 Drop and Insert * 30403010
D404 DDS & Fractional T1 30404010
D406 SLC 96® Derived Data Link 30406010
D408 SLC 96 Signaling State Analyzer 30408010
D424 Modem Option 20027273
* Two D403 Option Cards are required for
DS3 Bi-directional testing.
ACCESSORIES
D555 Non-Intrusive Probe 30555020
Thermal Printer 30031722
Printer Cable 04802233
Printer Paper 06001757
Serial Cable (null modem) M-F 30031422
F-F 30031431
Bantam Patch Cords (6 ft.) 30031350
310 Patch Cords (6 ft.) 30030316
Padded D400 Carrying Case 30031730
Padded D450 Carrying Case 30030771
CLEI CODES
D400 Digital Test System T1TDE058AA
D450 Digital Test System T1TDE068AA
SLC 96 is a registered trademark with AT&T.
4/95
811-572-002
Wilcom
P.O. Box 508, Laconia, NH 03247
Technical Assistance: 800/343-5327
Customer Service: 800/222-1898, Fax: 603/524-3735