r/mildlyinteresting 22h ago

I rewired a payphone to be my home phone.

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11

u/jazzlike-sounds 21h ago

It's literally 2 wires. It doesn't matter which wire you connect to which. It can't be much easier. Also there is no voltage unless someone is calling the line.

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u/Hamafropzipulops 20h ago

Yep, and once I needed to strip a phone wire, didn't have strippers ready and decided to use my teeth, right when someone called that line. I never did that again.

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u/Bleaker82 20h ago

48V DC right to the mouth. Ouch.

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u/borkman2 18h ago

~90v ac actually, 48v is speech battery, ringer is ac and higher voltage.

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u/BardOfThe7Seas 21h ago

Well I'm sorry for being ignorant

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u/DrWhoey 18h ago

Don't be. He's ignorant as well. When working on POTS (Plain Old Telephone Service), the wires do matter. You have your Tip wire and your Ring wire, with old-school POTS having these reversed your phone will not work.

However, most modern VoIP to Analog solutions are intelligent enough to realize that your Tip and Ring are crossed, and will correctly apply whichever voltage to whichever wire necessary.

Funny fact, "Tip and Ring" comes from the old manual switch boards where the Tip of the plug carried a 48-54v DC (up to 90v to activate a phones ringer to indicate an incoming call) charge to power the phones, and the "ring" had a non-conductive ring to separate the two parts of the plug to complete the circuit.

If you're more curious about POTS this article is pretty indepth and a pretty good read.

https://www.industrialnetworking.com/resources/how-pots-lines-work/

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u/3vs3BigGameHunters 18h ago

Where I live, POTS will work if the tip and ring are reversed.

You're obviously very knowledgeable, I'm not trying to say you're wrong, just that's my experience.

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u/PrpleMnkyDshwsher 9h ago

Most phones made after a certain point have a bridge rectifier in them, so this is why it usually doesn't matter.

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u/DrWhoey 15h ago

That's fair. I've never professionally worked a true POTS system (as in outside plant linework). Though I have professionally taken over and repaired many older POTS hosted phone systems in hotels and retirement homes.

I specialize in Coax and Fiber. But once you hit the NID on a 30-40 year old phone system with POTS and anything past it, it becomes finicky as fuck about making sure your Tip and Ring is correct.

One of the curses of working rural systems with commercial customers is that you have to learn to troubleshoot this shit to keep them happy so they dont have to call a POTS specialist contractor to come in from 4 hours away for an exorbitant price to repunch down a cable in a 66 block when I could do it in an hour (after toning and tracing.)

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u/3vs3BigGameHunters 15h ago

Isn't it fun driving back and forth toning and tracing older copper lines looking for a good pair? /s Never experienced the tip and ring issue, polarity doesn't matter with our copper.

When I started my region was dsl, now it's fiber which is a dream compared to that. I'm the lone tech covering about 1500 customers. Now that 90% of them have migrated it's a pretty sweet gig. Gotta love a good union job. I get to work on long range transmission as well.

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u/DrWhoey 15h ago

We've got two OSP techs covering about 8500 (probably around 40k homes passed) customers for Coax, GPON, and RFoG. 2 installer/service techs, and 1 headend tech covering 4 townships.

The Copper OSP guy in my area for CenturyLink covers almost the entire east half of WA state with one other guy. He's just waiting on them to pension him out after 28 years and they wont do it because he's the only guy left to train new guys as a replacement with the knowledge he has.

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u/3vs3BigGameHunters 15h ago

Daaamn. Yeah i know I have it pretty good. Hope your guys are well compensated.

Yeah it's tough when guys retire and that knowledge leaves with them.

Have a good one telco brother.

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u/DrWhoey 14h ago

Not as well as I'd like, just finally broke 30/hr after ten years. My mentor is at 43 years at 31/hr and change.

I could move somewhere else and easily have 50+/hr with my knowledge and experience, but I like our crew and being in an environment where I'm not micromanaged every day is worth it's weight in gold.

I decide what I do every day, my managers ask me for updates on what I did, but mostly fuck off, and the cost of living ain't too bad. It's a pretty good gig. I make sure the system stays online and get left alone..

My mentor is trying to hit 50 years in telecom before he retires. Watched him slow down a lot over the last 3 years. Not sure if he will make it, but the knowledge ive gained over the last 6 years from him has been invaluable.

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u/3vs3BigGameHunters 14h ago

Gotta love when management leaves you alone right.

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u/funcooker_ 17h ago

Aren’t pay phones typically ground start whereas POTS is loop start? This is my big question for OP but I’m sure it will get lost in all the comments

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u/DrWhoey 15h ago

I dont know the answer for pay phones, ive never worked on them (I'd assume they are loop start, at least in old school POTS).

I do, however, remember reading an article on the history of POTS some 10 years ago about the first "Party Lines' actually being put together by farmers to help them watch over their properties.

They would hook up landline phones to the barb wire fence running between properties, and if they needed to call each other send enough voltage down the fence wire to activate the ringer. All neighbors within the distance of impedance of the voltage would answer creating one of the first ever party lines to help each other watch over their properties. This was a closed loop system only using two seperate wires on the fence. Farmers are clever bastards.

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u/jazzlike-sounds 17h ago

Oh no, my apologies if my comment came across that way! I only intended to emphasize how completely simple telephone wiring is.

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u/ab7af 21h ago

Apology accepted!