Q: is it possible to download just one playlist onto my husbands new ipod nano

Hello sylviafromkendal,

With an iPod, you are able to sync music from multiple iTunes libraries to the device.  If the iPod is configured to manually manage the content, then please follow the directions in the first article below.  If that is not the case, then you will need to enable the manually manage music and videos option is turned on.  

Manage content manually on your iPhone, iPad, and iPod - Apple Support

Thanks for using the Apple Support Communities!

Cheers,

Alex H.