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5.3) General Information
5.3.1) Cables tested:
The CableRater is intended to work with coaxial cables exhibiting a 75 Ohm
characteristic impedance. Common cables include all types of RG-59 and all
types of RG-6. The CableRater also works with RG-11, RG-12, and cables in-
tended for aerial or direct burial applications.. as long as they are 75 Ohm cables.
Cables with connectors other than type F can be tested with the appropriate
adapters.
5.3.2)
The CableRater Receiver is a sensitive Radio Frequency (RF) Power meter.
In some cases, the RF energy in the air (over-the-air signals) is more powerful
than the signals in a typical cable TV distribution system. Over-the-air signals
include RF from nearby TV or Radio stations, Cell Phone towers, Pager towers,
Ham Radio operators, Microwave links, etc.
A distribution system that is in proper operating condition ‘shields out’ these
over-the-air signals, so they don’t interfere with the cable TV signals.
However, a distribution system that has faults, for example, a shield(s) on a
coaxial cable is open, can allow over-the-air signals into the system. This is
called “ingress”. Ingress will often result in poor TV picture quality on specific
channels (whose frequency is the same as the ingress signal).
If the CableRater is connected to a distribution system with ingress, the ingress
signal might be measured by the CableRater, causing an error in the Loss mea-
surement.
The distribution system will not operate properly if there is ingress. So, if in-
gress is detected by the CableRater this problem must be corrected before per-
forming a Loss Test. Refer to section 9.3 for instructions on testing for ingress.
