A brief K4 audio sample can be downloaded using the link at the end of this email.
This recording hows how the new K4 noise blanker algorithm can reveal a signal buried under loud noise. It also highlights the effectiveness of the audio-peaking filter (APF) when listening to a very weak CW signal. This was recorded on 17 meters, CW mode, in a 1 kHz bandwidth. Both receivers are turned on, tuned to the same frequency, and the recording is stereo. There's a slight delay between main and sub RX audio as the settings change; this is due to tapping A>B to copy the main RX NB and APF settings to the sub RX. Things to listen for (T in seconds): T0: S-9 noise masking very weak carrier T7: Noise blanker turned on so that only atmospheric noise remains; carrier now barely audible T14: APF turned on, 30 Hz BW; carrier clearly audible T23: Carrier disappears, leaving band noise only http://ftp.elecraft.com/K4/K4_audio_samples/K4%20NB%20demo%201.mp3 73, Wayne N6KR ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
