“Hard Line” phone systems are just historical terminology for old using a physical twisted pair 24 AWG wiring to connect private, and commercial telephones to a central patch board (kind of like a Local PBX board) through overhead, and underground cabling. “Just think of everything being physically connected by wire, and the typical wireless item, back then, being the cordless handsets using tuners recognizing the bottom station on the desk or kitchen counter. Hope this puts things in a little better perspective? When

was Dalex used for its first product? Why?