Does anyone know where I can download a users manual for the above? I bought the phone dirt cheap at goodwill, because I need a speakerphone. I would've thought it was pretty basic, but I can't figure it out (sigh) It's got an intercom, which I thought was speakerphone, the handset works, but I can't figure it out either! The manual has to be cheap ($5.00 and under) or better yet, free!