Like the phones that have a special plug and everything, the cord one still work when the electricity is out and they don’t seem to have batteries in there, so how and why do they still work
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They don’t take much power to run. The lines that run to the phone to connect them to the phone company also have a power wire that runs into them. The power is supplied by the phone company who have back up power in the event of an outage.
Plain old telephone services (POTS, for real) phones don’t require any power unless they’re ringing or somebody’s talking.
When you would receive a call, there’s literally a switch that closes a circuit, and from the telephone central office (CO, the closest facility serving your area) that circuit sends 105V to the phone, triggering the clapper to rattle back and forth against the bells, making it ring.
When you took the phone off the cradle, a different switch was triggered to start the lower voltage powering the ear and mouth (E&M) circuit.
Back at the CO, these switches were in two-post racks, and there were rows of batteries much like car batteries that provided the power. There was a regular power line to the CO, charging the batteries, but of course in a power outage, the batteries would keep working for some time.
If you want to keep going, https://en.m.wikipedia.org/wiki/Telephone_exchange
The old telephone system had batteries that sent power over the phone line. If the power went out, the phone would have power unless the phone line was cut. How long they lasted depended on how many lines there were connected to it, how old the battery was, and how many calls were made. They could last a few hours to several days.
Many now have landlines through cable service. They have battery back ups too, either in a box on a pole or along the street, or in a box inside the house. They typically provide power for up to a day or so, if the battery is new, but there are several added connection between the house and the telephone system, and if any of those has lost power with failed backup power you still won’t get a connection.
The simplest answer that is true is that the electricity is provided through the phone line. Phones did not need to be plugged into a power outlet until answering machines (voicemail for the ignorant) got built into the landline phones.
Canada here: we moved last year and experienced exactly this when a strong storm knocked out power for half the day yesterday. Our landline runs through our ISP’s modem, and we had no signal. The mobile networks were spotty at best; calls were choppy, texts barely went though, and data was non-existent unless you sent a km or two away
Those old phone lines carry (a little bit of) power, enough for the phone.
When you have a power outage you lose the power supplied by high voltage lines to your home, but that’s completely separate from the phone lines.
The telephone cable supplies a very small minimal amount of energy required by the landline to work. This is arranged by the telephone provider.
In a similar spirit we also have Power over Ethernet PoE. Which allows power to be transmitted over ethernet wires. So even when the lights go out, your internet access doesn’t.
*IF* your landline service is from the telephone company and they are still wired for POTS (literally “Plain Old Telephone Service”), their system has its own voltage over the wires, independent of the electric utility.
Increasingly, even so-called “landlines” are VOIP (“Voice Over Internet Protocol”) which runs via your internet router. so if your phone service is from a company like Comcast, or in some areas also AT&T, if the power goes out your router goes out, so your so-called “landline” is also dead.
# Because it was powered by the Telco, not your house. Unless the telco lost power, it still had it.
the telephone line itself supplies power. spikes and drops in voltage on the line determines if it’s busy calling or free.
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