Hi, Adrian: I have found: http://www.elecraft.com/K3/K3FAQ.htm to be helpful.
Here is a quote regarding NR: QUOTE How does the Noise Reduction work? NR depends on correlation of the present input with previous input. The system does not actually provide Noise Reduction; it provides Signal Selection. In other words, its default is to pass nothing at all. It has to believe there is a signal present, and then it builds a filter, or set of filters, around the spectral components of the signal it thinks is there. Random noise has no correlation, voice has moderate but not perfect (unless you whistle a pure tone) and CW has excellent correlation. As a result, noise is heavily suppressed (no filter is built to pass it), voice is partially suppressed (hence it needs some additional gain to compensate for this effect so the same AF level will produce about the same audio level with a moderate S/N speech signal) and CW is hardly suppressed at all (hence it does not need any gain boost). NR is not recommended in Data Mode. Data is already getting a matched filter in the demodulator. You might lose a few symbols as the NR settles around the signal, and it might suppress a very weak signal that you could otherwise copy. NR in the end is intended for modes you listen to. UNQUOTE Hth. Brgds, Dave, N3HE -- View this message in context: http://elecraft.365791.n2.nabble.com/MCU-4-42-Beta-Firmware-tp6813673p6815465.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
