Information
Cable Subscriber Installation and Test Guide
Home Leakage Pressure Testing and Ingress Mitigation
Problem: There are many devices in the home that emit RF signals, including cell phones. Ingress that interferes
with services can enter the home coaxial network at any point where the integrity of the grounded shield is
broken. Some examples include older devices with poor shielding, bad connectors, loose connections, and damaged
cable. Because the source of the ingress and possibly the nature of the leaks are intermittent, the disruption to
service can also be intermittent. When technicians don’t have a good, efficient way to test for ingress/leakage
repeated service calls are more likely. When ingress occurs, there is potential for disrupted service to multiple
customers on the same node. Anywhere there is a leak, there is also a potential for ingress – the leak is like a bi-
directional antenna.
An ingress scan is often required at installation and service calls to verify that no ingress is coming from the home.
The technician connects the meter to the tap or ground block looking back into the home network. If ingress is
present, it will be seen in the displayed scan. This assumes that the ingress source signal is active at the time of the
test. If it shows that there’s a problem, it doesn’t indicate exactly where in the home network the signal/noise is
getting in. The ingress scan is a good test and is especially useful in troubleshooting ingress in the cable plant.
A leak detector can be used to look for leaks in the home, but this requires a very sensitive specialized instrument,
as the cable signals within the home are at a relatively low level.
Solution: RF “pressure tests” of the home network are now used to verify shielding integrity and keep leakage
from impacting devices in the home and keep on-air signals from entering the network. For the home network
pressure test, high level signals are injected into the drop from the tap, or into the network from the ground block.
The signals are at a much higher level than the signals from the cable network (+60 or +40 dBmV) so the leaks
from the network will be accentuated. The technician walks through the home with the meter in the leakage mode,
and it emits a tone when a leak is detected, and the tone pitch increases as the detected field strength increases.
This enables techs to find exact points of failure – a much quicker process than trial-and-error.
The Home Leakage Test Kit includes a hand-held Seeker HL Transmitter that generates two frequencies that can be
set at two levels. The receiver is the technician’s DSP or OneExpert (ONX) meter with an antenna on the input.
This means there is no separate meter required to do this test.
Fiber Installation
Problem: Fiber to the home is becoming more common, and with
consolidated workforces, subscriber installation and service is
performed on either coax or fiber. Many are familiar with the need to
test the coax side, for performance verification and troubleshooting.
Testing fiber is also required, because without testing 20 to 50%
of homes don’t pass at first install and/or turnup, resulting in three
additional tech dispatches in more than 10% of cases.
Solution: Fiber testing is simple and saves time as techs get to the
root of problems quickly. A feature of the OneExpert instruments is
the OneCheck Fiber application, which incorporates both inspection
and optical power tests as part of a consistent, repeatable automated installation/service test process. The tech
is guided through a step-by-step process and test results are collected for analytics to ensure consistent process
compliance and enable continuous improvement.