--- In [email protected], "i2phd" <[EMAIL PROTECTED]> wrote: > > --- In [email protected], "sailingto" <sailingto@> wrote: > > > > Bottom post or top post for this group? I will post this reponse > > to top and change to bottom if that is the groups preference. > > Hi Ken, > > there are no firm rules. Personally I use the method of usually > interspersing my answers to the relevant parts of the message of the > correspondent. A bit more work, but maybe clearer messages.
I also like the interspersing of answers - helps keep everything straight - especially for me when I'm writing. >> I FINALY figured to swap the I & Q and now it is correct freq >>read > > Good. Swapping I and Q does not get rid of the image. It just mirror > the frequency scale around its central point. So there is the > possibility that you are convinced to receive the right signal at the > right frequency, but instead you are receiving the image frequency, > mirrored at the right spot because of the I/Q swapping. Well, I set the soundcard to 96,000 giving coverage from about 7.000 to about 7.100 mhz - the main image is now at the correct freq and MUCH stronger than the images that appear at other spots. I think I am at the main signal, but can be wrong. There was one image at about 7.037 mhz at -70db with the main signal at 7.050mhz at -45db. Transmitted CW signal was at 7.050mhz. The soundcard in my notebook is a RealTek High Defination and for the line-in has settings for "48,000 CD quality" and "96,000 studio quality". Winrad works nicely with both settings, where PowerSDR program has dropouts even with the 48,000 setting. It does seem to work, if I set Winrad at 96,000 and the sound card at 48,000 - the band width is from about 7.000 to 7.100 (a bit less, just rounding off), but the "grass floor" of signals is more of 7.035 to 7.075 or so. I change settings in soundcard to 96,000 and I have grass floor of noise all the way from 7.0 to 7.1 - and will receive signals in those areas. You can see the noise floor dropping off at the edges went the 96,000 is set. With 48,000 setting, the noise is much sharper drop off. > There is a way to be certain of having the I/Q connected correctly. > On 40m you can find only LSB signals. If you have a correct > demodulation with the LSB button in Winrad pushed down, then I/Q are > ok. Otherwise, if you have to set Winrad for USB to listen to >signals > on 40m, then either swap physically the two channels to the sound > card, or swap them logically with the choice in Winrad itself. Last night the only signals I heard in the low end of 40 meters that is covered by the Softrock Lite were Spanish and I think they were correct on LSB. Thank all of ya'll for the responses in helping this newbie get started with SDR. 73 de Ken H.
