If the batteries are dead or out of my Olympus DM (420, 520 or 620) Digital Voice Recorder, will it run if I have it connected to the Olympus A-514 AC Adapter.

Yes, the Olympus A-514 AC Adapter will power the Olympus DM model digital voice recorders and allow them to function normally.  In order to use the device solely through the AC Adapter, you will need to put the device in an AC mode.  To do this:

1. On the Recorder, go to Menu > Device Menu

2. In the Device Menu, go to USB Settings > USB Connect > AC Adapter

Now, when the AC Adapter is connected, the device will function normally with needed batteries.

Verification Source: In-house testing