On Saturday, August 07, 2010 09:49:35 pm g did opine: > On 08/07/2010 08:30 PM, Bob Goodwin wrote: > <snip> > > double clicking 1st in list of coax cables, 1671a, produces spec sheet; > > https://edeskv2.belden.com/Products/index.cfm?event=showproductdetail&pa > rtid=3462 > > scrolling down page shows table; > > Nom. Attenuation: > > Freq. (MHz) Attenuation (dB/100 ft.) > 500 15.0 > 1000 22.2 > 2000 32.8 > 3000 41.2 > 5000 54.9 Those figures are getting really close to being a good dummy load, that is like putting in a volt at 2Ghz, and getting a hair over than .0005 volt out. Low loss in this case is only in the mind of the copy writer, whose job is to sell the cable. At 5Ghz, assuming no wrinkles or bends to cause a reflection, it IS a good dummy load, with a VSWR so close to 1/1 as to not be detectable without some very fancy measuring gear. The round trip loss of 109.8 db is a dummy load even if the far end of the cable is shorted or unconnected. -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Vote anarchist. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
