Neal wrote: > > > It is my opinion that precipitation should still be considered in > calculating propagation reliability for both major nodes (operational > fixed, i.e. Tower to Walker) and street downlinks (AP to mobile, i.e. > Walker to Loring Park laptop). With some of the downpours and > electromagnetic disturbances in the Cities, I would <not> rule out the > effects of these conditions. I agree that it should be considered. I've seen the 2 gig studio to transmitter links for some of the local TV stations and the 5 gig satellite dish to IDS link for the local MDS company fade during hard rains but we don't have the option of using large fade margins like 40 db. We just don't have that much transmitter power to play with and 24 db is the largest common antenna size I've seen. With 30 mw transmitters and 24 db antennas a 10 mile link only has about 10 db of fade margin. Plus this isn't taking into consideration interference and the higher noise floor that we're going to be seeing as the band gets more crowded. I've heard enough people say that 10 mile links are doable that I think it should work. I think we'll just have to get something up and running and see what the error rate ends up being. If it ends up being a problem we can start looking for more antenna gain or add amplifiers. > > IIRC, I read a propaganda sheet from a manufacturer of ACSB (Amplitude > Compandered Sideband) equipment that noted of the failure of an 800 Mhz > (trunked?) system due to rainfall in Florida. > > Neal: nkras at nkras.dsl.visi.com > > _______________________________________________ > Twin Cities Wireless Users Group Mailing List - Minneapolis/St. Paul, Minnesota > http://www.tcwug.org > tcwug-list at tcwug.org > https://mailman.real-time.com/mailman/listinfo/tcwug-list > -- Bryan Halvorson bryan at edgar.sector14.net