美国BIRD鸟牌负载DA25F15，DA25U15，DA25F30，DA25U30，DA25-4F15，DA25-4U30DA25UHFSeriesDA25UHFSeries,470-890MHz,DASeries,DigitalAirLoads-areforcedaircooledloadsthatprovideafullyself-containedandconvenientmeansofdissipatinglargeamountsofanalogordigitalRFpower.DigitalAirloadsrequirenoplumbing,pumpsorcomplicatedinstallationandsetupprocedures.Thefourfandesignprovidesexcellentcoolingefficiencyaswellasextremelyhighreliability.)