Seeker D Lite Source Transmitter
User’s Guide
Document Num., Rev. 2
May 2018 Page 7
Introduction & Operation
Chapter 2
What is the Seeker D Lite Source Transmitter?
Overview
Mitigation of signal leakage within the subscriber premise is essential for the successful
operation of services both inside and outside of the coaxial cable network. To thoroughly
evaluate the potential for interference to subscriber services, VIAVI has developed a patent
pending approach to signal leakage measurement which will comprehensively test the
Aeronautical and LTE bands in both fully digital and analog cable systems.
Historically, signal leakage detectors have required high levels of sensitivity to
measure signal leakage radiating from the CATV network. Measurement within the
subscriber premise and the migration to all digital networks places even greater
sensitivity requirements upon the leakage detector, combined with a new requirement to
simultaneously monitor for signal leakage in both the aeronautical and LTE bands.
While these new requirements are a necessity to detect the potential for interference
between CATV and LTE services, the cost of designing, manufacturing and deploying this
new generation of leakage detectors has risen signicantly. As an industry leader in the
design and manufacture of signal leakage equipment, VIAVI has studied this application
model very carefully to develop a new and affordable method of signal leakage detection
within the subscriber’s premise.
Testing Approach
To overcome the high design and manufacturing cost associated with improvements in
instrument sensitivity, this system uses the Seeker D Lite Source Transmitter high output
signal source to replace the cable service at the subscriber’s ground block. The higher
levels transmitted by the Seeker D Lite Source Transmitter will increase the eld strength of
the signals radiating out of the subscriber network allowing a lower cost receiver to be used
for measurement purposes.
The Seeker D Lite Source Transmitter injects two carriers into the subscriber network, one
at 135–139 MHz and another at 611–615 MHz, supporting testing in both the Aeronautical
and LTE bands. The user may set the output level to 43 dBmV for home certication, but
also has the option to reduce the level to 23 dBmV should the subscriber network prove to
be too porous for pinpointing the location of a leak at the higher transmit level.
