Can you tell me how to set and get the watch going?

Hi
I have a Crane and viceroy radio controlled watch. It belonged to my brother who has recently passed away. I have had a replacement battery put in but I don't know what to do to set it and get it going. It's a lovely watch, would you please help me. I can't find any instructions.

Details on watch.
Face has on it...RADIO CONTROLLED 5ATM
AT 12 IT HAS NG... AT 3 IT HAS EL/AM...AT 6 IT HAS OK AND AT 9 IT HAS PM.
At the RH side there are 3 push buttons and the middle one has also a knurled ring around it. I really hope I can get it going. It also has a glass back.
Many thanks.
Bill Farmer