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Comment by OnACoffeeBreak | Hacker News Reader

100 Mbps Ethernet over barbed wire was demonstrated back in 1995. [0]

"Only four properties really affect the performance of most digital transmission structures. The "big four" transmission-line properties are impedance, delay, high-frequency loss, and crosstalk." Dr Johnson then goes to describe these properties in barbed wire.

0: https://www.sigcon.com/Pubs/edn/SoGoodBarbedWire.htm

P.S. Yes, this is the Dr. Howard Johnson of the famed "High-Speed Digital Design" book.

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And a hundred years before that, you had farmers running DIY phone setups over their barbed wire fences [1].

[1] https://gizmodo.com/barbed-wire-fences-were-an-early-diy-tel...

“ Each house had its own distinctive ring—two short one long, for example—and it was considered impolite to listen in on another's call.”

https://en.m.wikipedia.org/wiki/Party_line_(telephony)

A party line! Our cabin still has a grandfathered one with the distinctive ring. I think we pay 1/4 of the regular rate so we keep it despite everyone having a cell phone now.

I don’t think there’s anyone else on the line.

Got a funny spam call with a recording for some miracle septic tank treatment. It asked me to press 1 for more information and I can’t do that on a rotary phone. Scammers don’t understand their target market. (We also don’t have septic system, just an outhouse.)

What’s the baud rate on that setup like?

“3.” “3 Mbps?” “No. 3.”

I recall reading about one of the last public ones to get replaced back in the late 80ies, somewhere remote in Idaho.

Here we go - 1990: https://www.washingtonpost.com/archive/national/1990/07/13/p...

I guess you can, but your phone sends impulsions instead of DTMF tones, that nobody understands anymore. I'm surprised you can dial out actually

I got a 'digital phone line' through the local cable company installed about a decade ago. I had it hooked up to a rotary phone and I was able to dial out just fine with it.

Pulses can be detected by modern stuff just fine, when said detecting occurs on the same electrical circuit that the phone is connected to (for example, an analog to VoIP interface). They just can't be detected on some other circuit that has only the audio, for example when a conversion to digital audio has occurred. Only tones make it through such conversion. And while a VoIP interface capable of detecting pulses will happily do so (and convert them into something more useful) when it is presenting a dial tone, it won't do a conversion to DTMF for the benefit of IVR [0] mid-call. Devices specifically design to perform this task, however, will!

[0] https://en.m.wikipedia.org/wiki/Interactive_voice_response

> It asked me to press 1 for more information

If you have absolute pitch, and have a friend with absolute pitch (and I mean absolute frequency really not pitch), and are both freaks who can sing perfect sine waves... you could sing the dual tone for number 1 (697 Hz + 1209 Hz).

Since at this point we are talking about mutant alien phreaks, you should also be able to do overtone singing and squeeze out a 2 or a 3 column on your own which are 10% flat and sharp from the 2nd order harmonic of the first row 697 Hz.

Happy phreaking

> freaks who can sing perfect sine waves

Whistle, don't sing. Try it with a realtime analyzer which shows the fundamental being far more prominent than any harmonics above it, which means it's close to a sine wave. Then sing various vowels which will show as a series of harmonics whose amplitude ratios change per vowel but are never reduced nearly as much as when whistling.

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