Philips Avalon CTS M2720A, Service Manual

Page: 72 / 110

7 Troubleshooting Gathering Data
66
Both of these problems can be identified by observing the signal loss indicator warning on
the base station, in addition to dropouts on the recorder traces (see also“Range Definition” on page 67).
Refer to the
Service Support Tool Help for more information about CNR.
Gathering Data
Gathering the information to troubleshoot a potential RF problem will probably account for around fifty
percent of your job in determining if in fact you do have an RF problem. To gather data, you should:
1
Observe system performance
2 Question the user
Observe System Performance
While cordless monitoring offers many advantages, it can also provide challenges. The reliability and
quality of the signal transmission through the air and hospital walls is governed by a number of variables
which can be difficult to control. A cordless system cannot be as dependable as a hard-wired system that
transmits its signal through a wire. This is because signals travelling through a wire are not subject to
factors in the RF environment. The effect of problems in the RF environment on the cordless system
ranges from momentary loss of the signal to complete inoperability, depending on the situation. While
momentary signal loss is to be expected, frequent extended periods of signal loss need to be investigated.
Observe the system in operation. Does the system operation appear normal? If not, what seems abnormal
about it? What warning indicators are on?
Question the User
Determining exactly what the user is complaining about can be difficult. RF signals are subject to
interference and are inherently less reliable than signals passing through cables. Troubleshooting a cordless
system is therefore more difficult than a wired system, and requires special equipment and techniques.
The following checklist will assist you, when questioning the user, to gather data helpful for technical
support:
– If you observed problems during system operation, confirm they are problems of which the user is
complaining.
– Has the system always had these problems or are they a recent development?
– Is the symptom occurring on one channel, some channels, or all channels?
– Is the symptom occurring in a specific area or place?
– Is the symptom continuous or intermittent?
– How long does the symptom last?
– How often does the symptom appear?
– Does the symptom only occur at specific times?
– Does the symptom have “quiet” and “noisy” periods?
Area of Reach
The effective operating range, or the area of reach, of the system will vary depending on the geographical
and constructional characteristics of the building where the system is installed. We recommend that you
define the effective operating range prior to putting the system into operation.