rtl-sdr.com

There is a page on the SDR-Radio site that gives full information.
Alan

Yes, that is the first thing to do.
Front end filtering can improve even the best receivers.
Alan

Having looked a bit further I find https://www.rtl-sdr.com/new-rtl-sdr-dri ... r-console/ which appears to suggest that in the presence of strong out-of-band signals performance may be improved.
Alan

Is it the Bias T you want?
All info on V3 here https://www.rtl-sdr.com/rtl-sdr-blog-v- ... ser-guide/ and just about everything you want to know on other pages.
Alan

If you use the right DLL
I've no more details except it is associated with this author https://github.com/ms-jdow/rtlsdr-Cplusplus-VS2010
Alan

Look at the help for your virtual audio.
They have a repeater function if you find it.
Alan

The usual thing is that Microsoft replaces the SDR driver with a TV driver..
Use Zadig again.
Alan

You will need a BPF filter if you use a direct sampling dongle.
Like 3.2 Narrow Band Pass Filter here https://www.irjet.net/archives/V5/i3/IRJET-V5I3705.pdf
Probably a good idea for any cheap radio.

Alan

Neither seems correct.
antenna -> Lna ->bandstop filter -> dongle ->USB PC is recommended.

antenna ->bandstop filter -> Lna ->dongle ->USB PC might be required if the LNA is not a good one.

Alan

100Hz steps for a digital television tuner seems overkill.
Is it is a limitation of the device itself?
Alan