User's Manual

SZZJ-A10~17LF-LCPA User
Manual
- 16 -
antennas have to be installed in the same direction, please install them only after the signal
quality is tested and the self-oscillation is avoided. If the directional antenna is selected, the
main directional angle should point to the tower antenna.
⚫ If the performance is poor due to weak signals or poor phone call quality, please adjust the
direction of donor antenna or change its position in order to obtain the best calling effect.
⚫ The wide band repeater supports all mobile operators or different mobile systems, so please
adjust the donor antenna direction to have balance between signals of different mobile operators
or various mobile systems.
◼ Donor antenna installation ---Notes:
⚫ Do not install the donor antenna during the rainy day with lightning.
⚫ Please follow the instructions to install the donor antenna.
⚫ It is a must that the waterproof shall be done to connectors of donor antenna and feeder lines.
⚫ In order to avoid interference, please note that the donor antenna should be far away from the
following objects of metal, high-voltage line, and RF antenna and high-voltage transformer.
⚫ Repeater is a two-way signal amplifier. So proper isolation between donor antenna and server
antenna is necessary in order to avoid self-oscillation. About the definition for self-oscillation,
take MIC and loudspeaker for example; if it is too close for each other, it could make big noise.
So the repeater can only run smoothly if alarm LED always remains GREEN color.
◼ The minimum distance between donor antenna and server antenna shall be more than 10
meters; again the direction of donor and server antennas shall be opposite.
As shown in the below illustration, the booster amplifies the downlink signal r from the tower and
send to the indoor antenna hereafter. If the distance between outdoor antenna and indoor
antenna is less than the required distance, the amplified signal R will go back from indoor
antenna to outdoor antenna. So it will lead to self-oscillation and reduce the coverage area, also
the bad calling quality could happen at the same time, and the worse is that the mobile network
could be influenced badly and the operators will finally come to shut off the repeater system.