Put ON a pair of switches for a total of 15dB reduction in gain.You can reduces anyone system in the products.
Turn ON the dip switches of GSM or DCS or WCDMA to reduce the gain of GSM system.
Repeater Commissioning
Downlink gain setting
First the alarm LED only indicates the downlink input power level, here we use color of Alarm LED to adjust the gain of
the repeater. Alarm LED color must remain green. As for the downlink working performance, it is a good working point
that Alarm LED maintains “Green” color with the intention of turning orange; here we refer as “edge point”. At this time,
downlink output power and coverage effect are stable.
And the equipment must be as far as possible away from overloading status of “red” (the equipment would hold
higher interference and depression ability at this stage). So we shall try our best to set the equipment near “edge
point” of green and intention of turning orange during engineering.
Setting of “edge point”:
Switch on the power supply after connection with donor antenna and server antenna, and observe ALARM LED.
• If it shines “orange”, use 1dB as step to reduce the gain until “green” turns on, then increase the gain 1~3dB
attenuation value until “orange” starts to turn on, then brings back 1~2dB till “green” is on, then fix the gain
and the repeater’s downlink output power reaches the perfect status.
• If it shines “green” then:
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Please check coverage effect firstly, if the coverage effect is good, the engineering has reached
expecting target, thus there is no need to do anything.
• To check whether the attenuation value has been set, if it is, use 1dB as step to increase gain until the
“orange” turns on, then brings back 1~2dB till “green” is on again , then the repeater’s downlink output power
reaches the perfect status.
• But if attenuation has not been set, it indicates that the input power is not strong enough to let the repeater
reach its good coverage.
If the coverage effect is not good, the donor antenna should be adjusted to get stronger input signal. It is
recommended that one person shall check the coverage effect inside the building when the other person is trying to
adjust the antenna or the repeater. At this stage, please make sure “Orange” color will not be generated by self
oscillation. Please take off the server antenna to check if it is self oscillation or not: if the Orange turns to be green, it
is self oscillation; if it stays as Orange, it is not self oscillation. Please follow steps in other page to turn Orange to be
Green.
Uplink gain setting
Standard: uplink attenuation values =downlink attenuation values
Remark
: Avoid putting more than a 5dB difference between the Uplink and Downlink. And Uplink gain must be equal to or
less than Downlink gain, it can’t be more in order to avoid interference with mobile network.
