Are you selecting/using the correct antenna port?
Are you entering the frequency in the correct format? Default is kHz, so you have to add three zeroes to get MHz or you can use the blue ‘MHz’ button.
For instance, just entering ‘100’ will put you on 100 kHz and you won’t hear much. Entering 100,000 will do the trick and you’ll be on 100 MHz. Or enter 100 then press the blue MHz button.
This has come up so many times over the years.
The RSP’s are good, sensitive receivers and will get you listening in seconds, even with just a few feet of wire as an aerial.