I have plugged the 3.5mm end into the headphones socket of the tape deck, and the USB end into my PC, then started Audacity. However, the only three options I have in the recording device dropdown are for other things. I tried all three, but none of them work with the tape deck input.
If Windows doesn’t see it, Audacity won’t see it either.
The Berhinger UCA 202 is a popular and inexpensive audio interface with line-inputs,* but it does cost more than your USB adapter cable and you’ll need different cables for the RCA inputs.
Line-level inputs are compatible with headphone-level signals, but microphone inputs are not. So… Do NOT buy a regular “USB soundcard” because they are like laptops with only line-in and headphone-out.
OK, thanks to both of you for the replies. Guess this cable is going back then.
I looked at devices like the Berhinger UCA 202, but was hoping for something I could just plug into my existing tape deck. My previous PC had a line in socket, and a standard 3.5mm jack to jack from the headphones socket to the PC worked fine. This new PC doesn’t have a line in, which is why I was looking at a cable like this.
but was hoping for something I could just plug into my existing tape deck.
A “simple cable” won’t work because you need to convert analog (headphone) to digital (USB). Presumably, your existing cable has (or should have had) a chip (and some other components) built-into it. I have seen guitar-to-USB cables like that.