what is a false mirror freqs?
It's oscillator signals, that shouldn't exists, in the scanner that works as a mixer and creates other frequencies where you can hear a transmission.
I made a test on my SDS100E to see how bad it was, it's always worse in SDR receivers than in conventional receivers like BCD536HP.
I generated a strong signal from a RF signal generator and tuned around in the frequency band to see where those mirrors appears, and it's pretty bad in SDS100. In digital mode you don't hear those mirrors as you only listen to the decoded analog audio from the digital signal, but will compromise reception just as much as in analog mode.
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/Ubbe