I think it is a DME but can't seem to tell what kind or find a manual on how to operate it.
I can't seem to find anyway to enter a frequency into it.
Any help would be appreciated.
OK a little research has yielded that is not a DME and that DCE is relevant. Appears that it is wired into the two VORs and computes distance and speed by triangulating off the two VORS that are dialed in. Since one of the VOR's in the plane is INOP then I assume this device in INOP until the VOR is fixed.