产品名称：BLACKBOXME721A-M-R3型号：ME721A-M-R3品牌：BLACKBOX描述：Flexible.UsetheminpairsorwithourME800A-R3.Pushesdatamorethan5miles(8km)at2400bpsorupto1.2miles(2km)at19.2kbps.RoHScompliant.规格：Foraninterface-poweredmodem,theSHM-NPRreallypacksapunch.Forgetaboutthe50-foot(15.2-m)RS-232limit.Thissimple,plug-inSHMpushesdataupto1.2miles(2km)at19.2kbpsormorethan5miles(8km)at2400bps.This4-screwSHMhasaDB25maleconnectorthatplugsintoyourterminal.Toconnectyourasynchronousdevicestoahost,useapairofourSHM-NPRs—orasingleSHM-NPRandaShort-HaulModem-BAsync(ME800A-R3).TheSHM-NPRispoweredfromtheRS-232interface.Ifyourdevicedoesn'tprovideinterfacepower,usetheME800A-R3ononesideoftheline.NOTE:Mustbeusedinpairsor,ifyourdevicedoesn'tprovideinterfacepower,usetheSHM-BAsync(ME800A-R3)ononesideoftheline.)