Need to change battery in my used Land Rover. I do not have the radio code to reprogram after I put in the new battery.

You can connect a 12volt battery through the cigarette lighter this should keep the code in you radio just be carefull as the battery terminals will hav e voltage on them so dont short them out or touch metal work with the + wire

mzh

Take another 12v battery apart, (also a little UPS 12v battery works well) wire two thin wires SECURELY on the poles of battery and to the thick wires of the car, (attention the polarity, + to +, - to -, so the batteries now are in parallel) and tape the wires.
(Do not try turning on the car meanwhile)
You can now change the main battery without losing your precious code (;])
Good work !

Get some jump leads and another battery of car, connect the leads to the terminals after you have loosened them make sure they stay connected while you remove the battery this way the radio will remain powered and you will not have to put in the code