
The Keller House intercom system uses a dial so that users could pick the room they wanted to contact. Photo by Ann Belser.
The Keller House intercom system uses a dial so that users could pick the room they wanted to contact. Photo by Ann Belser.
The Keller House intercom system uses a dial so that users could pick the room they wanted to contact. Photo by Ann Belser.
The Keller House intercom system uses a dial so that users could pick the room they wanted to contact. Photo by Ann Belser.