SDA-5000 SERIES STEALTH DIGITAL ANALYZER
5
Detecting ingress in the field
When detecting ingress in the field, first the operator looks at the ingress present
at the field testpoint using the spectrum display on any of the receivers and then
switches to reverse ingress/noise to see the ingress at the headend for comparison.
This time-saving procedure helps in locating sources of ingress. An adjustable
dwell time ensures that even intermittent ingress is detected. The preamp and
lowpass filter also assures that even low-level ingress is seen. The preamp and
lowpass filter on the SDA-5000 assures that ingress can be measured on devices
with bidirectional testpoints or testpoint values of 30 dB or more.
Graphical reverse testpoint compensation
PathTrak Field View option
When a network is equipped with the JDSU PathTrak Performance Monitoring
System, system technicians can benefit from the ultimate tool to combat ingress –
the PathTrak Field View option for the SDA-5000. With Field View, the SDA-5000
receives a return path headend spectrum broadcast from the PathTrak unit and
compares it with a return path spectrum at any field testpoint. The side-by-side
spectrum comparison instantly reveals to the technician whether the ingress
source is originating at the technician’s current testpoint or at a different location.
The comparative spectrum technique reduces noise/ingress troubleshooting time
dramatically, since the technician can immediately verify whether corrective
action performed in the field (local trace) results in improvement in the headend
spectrum (remote trace).
The Navigator user interface, common on all
JDSU SDA meters
Comprehensive testing
The SDA Series provides an extensive set of signal analysis features designed for
proving and improving network quality. Its key capabilities include level mea-
surement, analog and digital signal limits, tilt measurement, scan measurement,
in-service carrier-to-noise measurement, hum measurement, modulation
measurement, and local amplifier alignment with loopback tests.
Level measurement
The single-channel level display shows both video and
audio levels (either single or dual sound/ NICAM) and
the difference between the two
The SDA instruments have a comprehensive single-channel level display with
tuned channel, video frequency and level, audio frequency and level, and the
difference between video and audio carrier levels.
Making accurate digital average power measurements is addressed with the
digiCheck measurement function. The digiCheck feature is compatible with most
non-bursty digital modulations in use today (that is, 16, 32, 64, 128, and 256
QAM, QPR, QPSK, VSB, and CAP16 ).
Analog and digital signal limits
Digital channel average power measurements can be
made using the digiCheck™ feature
Analog signal threshold limits have always been a technician’s favorite feature of
JDSU instruments. Automatic limit checks provide a quick go/no-go status for
audio and video levels. The SDA Series extends this capability with a dedicated
digital limit set that can be applied exclusively to the forward digital carriers
defined in a channel plan. By assigning separate analog and digital limits, test time
is reduced, since no calculation is necessary to determine if analog and digital level
relationships are within system specifications. Analog and digital limit capability
is available in both the Scan and Autotest modes.
JDSU [ JDS UNIPHASE CORPORATION ]
