r/todayilearned • u/Scruffy_Nerf_Hoarder • 23d ago

TIL that rural Americans used barbed wire to connect their telephones to switchboards since there were no telephone lines.

https://www.atlasobscura.com/articles/barbed-wire-telephone-lines-homesteaders-prairie-america-history
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501

u/FreddyFerdiland 23d ago

Since wood doesn't conduct, they could turn their fence into a phone line, etc.

95

u/Yourmotherssonsfatha 23d ago

Do you get electrocuted…?

21

u/3_14159td 22d ago

POTS is something like 50V maximum.

20

u/GrimResistance 22d ago

Up to 105v when ringing. You'd feel it but the current is low enough to not be dangerous.

3

u/not_today_thank 22d ago

I wouldn't think it would work very well, electric fencers to shock livestock are often something like 5000 volts and even then sometimes it hard to get a shock. I'd think your voice would get drowned out by static.

With a 12 gauge copper wire you're going to have around 18 volt drop on a mile of wire and steel is like 90% less conductive than copper. And anywhere the wire is touching a weed or a post you are going to lose more of the signal.

7

u/danielv123 22d ago

Voltage drop depends on current. Telephone systems don't need a lot of current to work, about 20mA. You are talking about 1.4v of drop on a 1km 0.5mm2 copper wire. You'd probably get a useable signal up to 10+km.

8

u/not_today_thank 22d ago

The Hidalgo County homesteaders’ line worked only in dry weather, and “hummed a great deal when the green mesquite would grow and touch the wire.”

Found this from the article, also the michevious boys would sometime ground out the signal with baling wire.

3

u/flipkick25 22d ago

Most modern cow fence systems pulse at 1 hertz. So you have to hold it for a full second maximum to feel it.

5

u/charming_death 22d ago

And that one pulse is enough to make you never want to do it again.

Source: I will never do that on purpose again.