User's Manual
9
Note that because the ampliers in the Cellular Signal Booster’s input
and output ports are tuned to the same frequency, oscillation (feedback)
between the Patch and Service Antennas can occur if they are placed
too close together (Fig. 5.) The effect is similar to that of a microphone
that is held too close to its output speaker; you will hear a loud whistling
(oscillation) noise. If a Cellular Signal Booster system experiences this
oscillation, it will jam the cellular system near your home and disrupt the
operation of both your and other cellular phones in the area.
There are three ways to prevent oscillation between the Patch and Service
Antennas. The rst involves increasing the distance between the antennas
(just as you would move the microphone away from its speaker to stop the
feedback.) The second entails reducing the amplication level of the Base
Amplier (similar to lowering the volume of the microphone’s speaker.)
The third is simple: turn the system off.
All three of these methods have been built in to the ClearCell + Plus
Cellular Signal Booster to prevent feedback. During installation, an ALARM
indicator on the Base Amplier lets you know if you are too close to the
Patch Antenna. Once installation is complete, oscillation detectors inside
the Base Amplier alert the Booster when potential oscillations are present
so that it can automatically reduce the Amplier’s amplication level.
Finally, if the Cellular Signal Booster cannot sufciently reduce the level of
amplication, it turns itself off.
Feedback/
Oscillation
Radiation Feedback
Figure 5
Feedback Loop