We use the RADIO SHACK 12-260 model here, I went with the simple type ones as if you get the ones that has programmed spots for different counties and states then you have to keep programming those in as you move around the country side.
Mine does a channel scan when you first turn it on and stops on the active channel... Another problem is you don't always know what county you are in so what you are listening to may be many any miels away haha
I wired mine up with a radio shack DC AUTO ADAPTER plug and matched the right plug for the WX RADIO. This unit runs off 6VDC
This allows me to remove the batteries and plug this into my 12VDC Sockets in my trailer.
I got mine several years back when Radio Shack was alive and going strong. Don't know if you can still order these from AMAZON or not...

Roy Ken