If you are in an RV just install the needed 12 volt jack on the house system
if you are wanting to use it "out and about" get yourself a power supply.. Now these come in basically 3 flavors and I've used all 3 at one time or another for various devices
One is a plug in module (A Wall Wart) with a 12 volt "Accessory jack" This is a fairly low power device (I think it was rated 3 amps) and may or may not power your receiver.. I'd also not be too sure of the voltage regulation on this device but it DID what I wanted it to do when I needed it.
The second is a box with cord and 12 volt terminals and/or acc outlet
It is called an UNREGULATED POWER SUPPLY... Again, Not the best
The third is like the 2nd, but Regulated and that's what I design, build and use. I highly recommend.
Another option is portable.. A 12 volt Jump Starter battery pack.
I've also done it with 8 D Cells (2 4D holders some wire and a socket) worked great... Lasted lots longer than I expected them to last.
