Telecom component characterisation
3261A Telecom Unit forms the core of a comprehensive component
test system. It is configured in conjunction with the Wayne
Kerr 3260B Precision Magnetics Analyzer to carry out a wide variety
of telecom-related measurements.
Telecoms Fixture model 1008 further enhances the test capability
by providing an interface to connect units under test such as
transformers.
Complete telecom transformer characterization
Automatic production testing of telecom transformers is available
with the 3261A. Transformers are characterized at the press of
a button.
Total Harmonic Distortion
Providing unrivalled Total Harmonic Distortion (THD) performance
this optional function displays the second, third, fourth and fifth
harmonic as well as THD. Measurements as low as -110 dB can be
carried out; the user can set a large number of preset fundamental
frequencies from 150 Hz to 200 kHz.
Longitudinal balance and transverse balance
This optional function provides longitudinal balance and
transverse balance measurements in line with IEEE 455, ITU
recommendation O.9 (O.121) and FCC 68.310 over the frequency range
200 Hz to 3 MHz.
Measurement capability is high, longitudinal balance accuracy is
±1 dB over 80 dB, ensuring that devices can be measured with
confidence.
The longitudinal and transverse balance of any component can be
completely characterized graphically across the full frequency band
enabling component performance to be analyzed in more detail.
Insertion Loss and Return Loss
3261A Telecom Unit measures Insertion Loss and Return Loss from
20 Hz to 3 MHz on transformers and POTS splitters.
The instrument can also measure and display many parameters
including Insertion Loss and Return Loss against frequency in a
graphical form - ideal in a design or development environment.
Swept measurements in graphical form
It is often important to characterize component performance
outside its operating range, especially during component design. The
3261A allows Insertion Loss, Return Loss, transverse and
longitudinal balance, and the usual basic transformer parameters,
such as Inductance and interwinding capacitance, to be displayed
graphically.
Sweeping the full frequency band for the particular measurement
the user can identify the maximum and minimum point on the graph and
a moveable marker displays the frequency and level. The graph axes
can be selected as either a logarithmic or linear scale.
Comprehensive test system
The key to the test system’s versatility and accuracy is the
combination of a precision impedance analyzer with a dedicated
telecomms test unit. This combination provides many advantages.
Where special interface methods are needed the 1008 Telecoms
Fixture is available, or customised fixtures can be configured using
a blank fixture to ensure high integrity measurements.
3261A Telecom Unit test system
incorporating 3260B Precision Magnetics Analyzer and Telecoms
Fixture 008
ADSL, ISDN and HDSL analogue line matching transformers and POTS
splitters
ADSL technology requires tighter specifications and additional
measurements when testing line matching transformers. The
3261A provides all the required measurements and performance for
ADSL technology, including Total Harmonic Distortion, longitudinal
and transverse balance, Insertion Loss and Return Loss.
It not only exceeds the required specifications but also makes
all the measurements automatically from the same fixture. For
the user it is just a case of connect and test, ideal in a
production environment, with no complex set-ups, special jigs or the
need to calculate the result from a number of voltage measurements -
the 3261A does it all.
The user is able to select the required line side termination
from a list of predetermined values. Equipment side terminations are
provided by the user and can be connected to the appropriate socket
on the 3261A. Once the termination has been fitted no further
interaction is required by the user.
Accurate DC bias current
DC bias current can be selected for Insertion Loss, Return Loss
and Total Harmonic Distortion.
This function provides high accuracy user selectable DC current
in the range 1 mA to 200 mA in 0.1 mA steps (to 20 mA) and 1 mA
steps (to 200 mA).
The total production test solution ... in a single fixture
Replacing many discrete instruments, complex jigs and difficult
measurements, the 3261A Telecom Unit provides all the functions
needed to meet the new telecom standards in a single multi-function
unit.
It also replaces all the hard work, high skill levels and
uncertainty of manual testing by handling all the complexity
internally and presenting the user with the information required
quickly and accurately. In a production environment it is just a
case of connect and test.
All the user has to do is press the start button and the 3261A
Telecom Unit makes all the measurements and displays a Pass/Fail
banner.
Technical Specifications
GeneralLine side termination: 50, 75, 100, 120, 135, 600,
900 Ω Equipment side termination: Customer is required to supply
centre tapped 1% resistor
Insertion Loss
Drive level*: |
-65 dBm to +20 dBm |
Drive level units: |
dBm, dBµV, V |
Frequency range: |
20 Hz to 3 MHz |
Basic Accuracy**: |
0 to -3 dB ±0.1 dB |
|
*Varies with DUT impedance |
**Varies with
frequency |
Return Loss
Drive level*: |
-60 dBm to +25dBm |
Drive level units: |
dBm, dBµV, V |
Frequency range: |
20 Hz to 3 MHz |
Basic Accuracy**: |
0 to 25 dB ±1dB |
25 to 30 dB ±2 dB |
30 to 35 dB ±3 dB |
|
*Varies with DUT impedance |
**Varies with
frequency |
Transverse balance (analogue voiceband)Drive level: 0 dBm
(0.775 V rms) Frequency range: 200 Hz to 10 kHz Basic
Accuracy: to 80 dB ±1 dB
Transverse balance (digital)Drive level: 0 dBm (0.316 V
rms) Frequency range: 10 kHz to 3 MHz Basic Accuracy: to 55
dB ±1dB (≤1.55 MHz) to 45 dB ±1dB (>1.55 MHz) 45 dB to 55
dB ±3 dB (>1.55 MHz)
Longitudinal balance (analogue voiceband)Drive level: 1 V
rms Frequency range: 200 Hz to 10 kHz Basic accuracy: to 80 dB
±1 dB
Longitudinal balance (digital)Drive Level: 0
dBm Frequency Range: 10 kHz to 3 MHz Basic Accuracy: to 55
dB ±1 dB (10 kHz to 1.1 MHz) to 45 dB ±1 dB (>1.1 MHz) 45
dB to 55 dB ±3 dB (>1.1 MHz)
Total Harmonic DistortionMaximum drive level: 6 V rms (±2%)
at the DUT Drive level units: Vrms, Vp-p, dBm Frequencies:
150, 300, 500, 600, 5k, 10k, 15k, 20k, 25k, 30k, 40k, 50k, 100k,
150k and 200 kHz
DC bias currentOutput current: 1 to 200 mA Step size:
0.1 mA (1 to 20mA), 1mA (20 to 200 mA) Basic accuracy: ±1% ±1 µA
(1 to 20 mA), ±1% ±10µA (20 to 200 mA) Compliance voltage: 22.5 V
(into line side termination)
Power SupplyInput voltage: 115 V AC ±10% or 230 V AC ±10%
(selectable) Frequency: 50/60 Hz
EnvironmentalInstallation category: II (in accordance with
IEC664) Temperature range: Storage -40°C to 70°C, Operating
0°C to 40°C. Full accuracy 15°C to 35°C. Relative humidity: up
to 80% non-condensing Pollution degree: 2 (mainly
non-conductive) Altitude: up to 2000 m
SafetyComplies with the requirements of EN61010-1
EMCImmunity: EN61326-1 Emissions: EN55022 Class A
MechanicalHeight: 150 mm (6″) Width: 440 mm (17
3/8″) Depth: 520 mm (20
1/2″) Weight: 14 kg
Order codes and options
3261A Telecom Unit Supplied with
mains lead, user manual, 8 BNC and link interconnecting leads
(for connection between 3260B and 3261A), 1JBLANK fixture,
short circuit trim fixture and HF compensation fixture |
|
1J3261B |
|
Note: - The 3261A can only be used in
conjunction with the 3260B Precision Magnetics Analyzer. |
|
Options |
Total Harmonic Distortion |
|
add /A to part number |
Longitudinal and Transverse Balance |
add /B to part number |
|
Accessories |
Telecom Fixture |
|
1J1008 |
Telecom Production Test Software |
PT3261 |
Blank fixture containing PCB and pins
allowing the user to adapt the fixture for a specific
component. |
1JBLANK |
Device specific fixture for a customer
transformer |
1JFIXTURE-01 |
|
Note: - The customer should provide a
drawing and sample of the particular transformer requiring a
fixture | |