rtl-sdr.com

About 2MHz is all you get in real time. There are programs that build up a spectrum in slices but that would take a long time to do 400MHz even if any actually is capable of such a scan.
I guess the RF Explorer uses a much higher sample rate.
Alan

I do not use that software. But the place to go is their group. Several posts describing what to do. https://sdr-radio.groups.io/g/main/message/45843
Alan

Presumably it just loaded the default Windows drivers, this is to be expected.
Simply set it up as described using the driver installer, Zadig.
This replaces the Windows driver.
Alan

The splitter will need to pass the DC without attenuation.
But for safety you need to isolate the Uniden with a capacitor.
Alan

HDSDR can do that, do not know SDR# plugins.
Alan

Division by 3 is simple. But to make it over 10MHz and linear seems very difficult. If it were done I don't suppose anything more than a display would be possible. If you do not want to scan then get a SDR that will cover 15MHz so that 10MHz will be alias-free. It would be cheaper and better than an...

And also a page on SDR Console site where you downloaded it, information on how to get it recognised once you have installed the driver with Zadig. The exact details on your model will be unknown until you identify it. You will have to experiment or do a Google, you should find something although so...

That's good if you are using a raspberry pi
It usually quits working after a few minutes on my Windows 7 machines, I need something like that.
I'll have to look.
Alan

I should say "I think it is included in that DLL"

If you follow the link I posted
Alan