Some interesting replies in this string.
Jerry and Faye, the number of bits provided by the A to D determines the minimum signal level. More bits means more sensitivity. I believe the higher end SDR (not the dongles for $17!) use 16 bit A to Ds. Dynamic range is also important. Lots of information available on line. But you are right. There is a practical limit based on noise. Tree, regarding ft8, Joe, W4TV's answer is a fine explanation. Its a combination, for a SDR, of the number of A to D bits and the capabilities of the software created by Joe Taylor. The shorter answer is, the signals are actually there.... Isn't technology great??!! So much to learn. And I may have to relearn some stuff should I have gotten some of the above wrong Ron N4XD Sent using https://www.zoho.com/mail/ _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
