If you don't mind the added bulk....try a 4-D or 4-C external battery
pack. I like it a lot. Never have to go inside the radio to replace
batteries. the battery holder, cord and plug at RS is less than $10
in total I think. Being a cheapskate, one thing I have started doing
is transferring my semi-dead D cells out of flashlites over to the 398
power pack. Not enough juice left for a strong flashlite beam...but
enough to power the radio for a good while.