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Intercom Answered

We have four old Nutone intercoms installed in our house without a master station. The intercom speakers say 3.2ohm on the back and connect with 3-wire. Is it possible to hook these up to an old receiver?


Thanks for the responses!


7 years ago

3.2 ohms is quite the load. I would guess the speaker is 32 ohms. Would make much more sense.

Seems totally possible to send that signal to an external device (your receiver).

On the speaker magnet it does say 3.2 ohms, which I thought was strange myself. These are probably from the early 60's. They don't appear to have microphones either. The "push to talk" switch looks like it switches back and fourth between two (one wire goes through a volume control) of the three wires that come to the unit and converges (I'm assuming positive, although not marked) into one wire which connects to one terminal on the speaker. The wire that I assume is negative hooks up directly to the speaker.

The speakers are the microphones -- when you press the switch, it switches the connections. I can't help you much farther than that tidbit; we have an el cheapo single-station intercom between the shop and the kitchen that works that way, though it has standard 8ohm speakers.

Find an old Nutone base station?

Yeah, then i've got no experience with this setup.

They appear to be wired in a series too.