On 2 Dec 2019 at 17:06, Paul Randall wrote: > It may be unrelated but a station very local to me on 2m transmits a > huge wideband splat of noise at the start of his FT8 transmissions. I > think what I am hearing is all the noise in his shack, the fan in his > qro linear etc, all picked up by his microphone which presumably is > still plugged in. With speech compression this can make a lot of power > before the FT8 tones start and suppress it. > > Paul G3NJV
I've often observed a similar situation on primarily (IIRC) 80m FT8 - there's (at least!) one station whose transmissions always start with a huge burst of what sounds like background noise. Unfortunately I haven't yet been able to identify which of the numerous stations on 80m FT8 is the culprit. My recently-acquired IC-7610 rig and I believe my previous couple of Icom rigs - IC-7600 and IC-756 Pro III - all had the facility for specifying the modulation signal source when in an SSB data mode. I use the USB-D1 mode, and on the 7610 I've selected the modulation input for this mode to be the ACC1 rear-panel socket. However, it does appear possible to select both ACC1 and MIC for the MOD input in USB-D1 mode which could cause problems of unwanted emanations if that option were to be selected. The 7610's default MOD input when in USB-D1 mode is ACC1 alone. I would assume that other makes of rig have a similar set of options for specifying the modulation input when an SSB data mode is selected; it shouldn't be beyond the wit of most operators to ensure that only the applicable option is selected via the menu system! --- Martin, G0HDB _______________________________________________ wsjt-devel mailing list wsjt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wsjt-devel
