As we mentioned in our recent HTC Thunderbolt review, there's no option provided in the settings to switch off 4G (LTE) and force the phone to operate solely on 3G (EV-DO). Obviously this is an issue when conserving battery is more important than reaping the benefits of LTE's ludicrous data speeds. Fortunately, we can thank the good old *#*#4636#*#* test menu for remedying this odd deficiency. This hidden menu, which became popular with the Nexus One and is available on most Android devices, allows you to enable / disable radio modes. On the Thunderbolt it lets you select between LTE+EV-DO, EV-DO only, and LTE only. Now you can have your cake and eat it too -- well almost. Follow the source link for step-by-step instructions.