Wow, that brings back memories. We had an intercom system in my childhood house, but I was too young to be allowed to use it when we moved in. As I got older (9-10) I was allowed to use but the thrill wore off when I realized it was easier just to yell down the hallway for my brother or parents if I needed them.
Going on memories from ±55 yrs ago, our base was this model...I remember the horizontal switches. The auxiliary ones were in other spots in the house.
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