Original sentence: All modern models will include a signal amplifier.Even the cheaper home-use models now provide around 30dB gain and many of the more expensive models provide over 50dB.This is due to the difficulty of filtering the correct signal out from the background noise, which will be amplified equally, and the limiting maximum signal power of the amplifier (typically from around 5 dBm or 3.2 mW)
Edited sentence: - bad choise of donnor antenna type and wrong installation without sense to minimization of the interferences (e.- bad choise of the donor site.- repeating of only part of band but operator using wider band or more bands (e.- used poor device generating in UL horrible noise and intermodulation products.All models will include a signal amplifier.By operator uncontrolled amateur installation of the pico/mini repeaters can be harmful from many reasons:.Even the cheaper home-use models (typically band selective) now provide 20dB - 50dB gain and many of the more expensive models provide over 50dB.Excelent highpower models offers gain around 100dBm (ICE function is welcomed as a improvement of the radio isolation between donor and service antenna).NodeG from Andrew) offering output power arround 10W).Standart GSM channel selective repeater (operated by telecomunication operators for coverage of large areas and big buildings) has output power around 2W, high power repeaters (e.There is also problem with noise amplification (especially in UL) and desensitization of the donor site.This is due to the difficulty of filtering the correct signal out from the background noise, which will be amplified equally, and the limiting maximum signal power of the amplifier (for picorepeaters typically from around 5 dBm (3.2 mW)).repeater is not supporting EGSM or is only for 900GSM but operator is using EGSM or GSM900+GSM1800 layers with single BCCH (Siemens(SAG) common BCCH) feature => call drops..).to high installation where it is not necessary, no shading by building where it is possible (for example by wall installation or suppresion of side/back lobes by chimney,..)) and without sense to donor site selection