phone works with ac-dc adapter (base unit), but when correct dcv is applied from a dc source, in-use light blinks, (as if incomming call). I am trying toadapt this for use in a news remote vehicle, coupled w/ a Telular phonecell. As I said, it works w/ the ac-dc converter supplied, (when run off the 5kw genset), but not with 7.1vdc supplied from dc bus.