Viewer update: I did a bunch of viewing with this viewer today showing friends etc. Once the batteries got down to 1.2 volt area, the camera started to malfunction. Installed fully charged batteries (1.5 or higher volts) tested with a digital meter, everything worked fine. There was a lot of video and picture viewing before the batteries had dropped to the above mentioned voltage. The 1.2 volt rechargeables would be useless for these viewers, even if bumped up to 1.38-1.44 voltage area as can be done with the Energizers.