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Technical Topics => SDR - Software Defined Radio => Topic started by: IQ_imbalance on November 05, 2017, 0328 UTC

Title: SDR-setting I/R gain?
Post by: IQ_imbalance on November 05, 2017, 0328 UTC

Could someone explain the difference between the gain settings in SdrDx for an AFEDRI SDR?  You can apparently set the RF gain at the SDR itself (in the SDR setup menu), but there's also a slider for I/R gain in the main software window.  How does one go about finding the optimal gain settings?
Thanks,
Robert

Title: Re: SDR-setting I/R gain?
Post by: Josh on November 06, 2017, 1649 UTC

What I do is find the spectrum where I have the most trouble as far as imd and so on, typically the ambc band as there are several broadcasters within 25 miles or so. Then I adjust the gain settings for no imd on that band and lock it down. Also be sure to check the noise blanker level, if too high this will stimulate imd due to nearby strong signals. The noise blanker setting is often overlooked in the search for imd sources and fixes.