Sonoma, I just tried your method on the original part with a 3v CR2032 coin cell and it indeed shows to be a com anode. However some pins did not light up anything confirming burnt segments and the OEM LDG-202A does not have the decimal point behind each digit. This EKL 2D-04C-BLUE is confirmed as a com. cathode which will not work with my particular radio. Thanks for the easy test method... shot the guesswork right out the window! It would be safe to say that not ALL older or different channel/main boards radios use the com. cathode as stated elsewhere for the 25 chassis.