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Seeker D Lite User’s Guide
Document Num., Rev. 4 May 2018 Page 9
Introduction
Chapter 2
What is the Seeker D Lite?
Overview
The new Seeker D Lite™ is a tough, convenient, and flexible leakage
test tool. The Seeker D Lite works by measuring tagged RF signals in
and around a subscriber’s premises.
This leakage detector assists in installation and troubleshooting by
verifying that the leakage within the subscriber premises is not great
enough to contribute to the cable system’s cumulative leakage index
(CLI). Leaks can also be important indicators of ingress that can hinder
communication on the return band, as well as affecting downstream
QAM channels in the LTE band.
The Seeker D Lite works in conjunction with the CT-4™ Channel
Tagger in the headend or the Seeker D Lite Source Transmitter at
the ground block. Both devices provide an uncompromising tagging
solution for active analog or digital systems and can be used to identify
and locate all RF leaks in both the Aeronautical and LTE bands.
Testing with the Seeker D Lite Source Transmitter
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 field 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 certification, 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.
The Seeker D Lite provides both a visual readout of the measured levels in uV/m and a
tone proportional to signal strength. To prevent false triggering this system utilizes Trilithic’s
channel tagging technique. To provide constancy with leakage levels typically found within
the subscriber’s premise in home cert mode, the levels displayed by the Seeker D Lite have
been normalized to represent the value of a leak at typical system levels. This correlation
between measured and displayed levels will assist the technician in evaluating the severity
and recording of a leak based upon established industry practices.