I'm jumping into this with some surface level knowledge so I apologize if the solution or cause is simple. I recently purchased a bladerf2 micro xA9 as an upgrade from an rtlsdr I had been working with for a few weeks. I loaded both the rtl and the blade into sdrangel to view a side by side and was surprised to find signals in the blade that were not present on the rtl. I had both tuned to 285MHz (blade) and 289MHz (rtl) with similar antennas and saw the following:
The signals on the blade correspond with an EDACS trunking system in Brevard County, FL located at ~850MHz.
There are a few more examples, ex. 868 or 915MHz packets showing up at ~330MHz and vice versa. These frequencies will be present regardless of the sample rate or bandwidth I choose, but will shift position when I change the center frequency of the device.
Ex, increasing the center frequency causes them to shift upwards in frequency, sometimes with a loss or gain of strength.
I've observed the same behavior in gnuradio and gqrx. Is this a known issue with a workaround?
Thanks!