Main channel: How to use phones and modems like it's 1992
Added 2025-05-19 00:22:23 +0000 UTCHello my patrons! Next up on the main channel we have some old school analog telephony. This (unfortunately) isn't anything like you would get from the Connections Museum, but I bring a tiny bit of that home with a way to use all my old modems along with a few phones.
I'm pulling a lot of nostalgia threads for myself in this video, so please forgive the indulgence.
A few updates after watching this video, I still have some wiring to do at home and I'm still looking for some extra devices to pair with this. I'm looking forward to some of the fun I'll be having with this, perhaps integrating it into some modern things while I'm at it.
Thanks for all the support!
Direct link: https://youtu.be/E7LYCERDnX4
Comments
If you haven't been, the Connections Museum in Seattle (https://en.wikipedia.org/wiki/Connections_Museum) has an amazing collection of working old telephony items, including switches and other exchange gear. Most of it's way over my head but seeing mechanical versions of things that exist inside semiconductors now is quite amazing!
Adam Reeve
2025-05-30 06:33:20 +0000 UTCThis is why ZMODEM was such a wonderful thing.
tim1724
2025-05-22 21:52:14 +0000 UTCOver the past year, I've gotten hold of a couple of old telephones, VoIP adapters, and modems as well. I really need to find some time to get Asterix set up and play with all of that again. This analog PBX makes it look so easy!
Peter Tirsek
2025-05-21 15:36:52 +0000 UTCI love this so much! You're right that the 56,000 bit rate is only supported from a digital line, and only if the entire phone network between the two modems only has a single analog section (at the user's end, typically). The 56K signal cannot pass through an analog-to-digital conversion and back again. The reverse direction or a connection between two analog modems are limited to 33,600 bps with V.34+ (up from 28,800 bps in the original V.34 standard). It's not 38,400 on the phone line. That one is only supported on that serial link to the PC. Also, by the way, those speeds come from the fact that the original IBM PC UART, the 8250, was clocked at 1.8432 MHz, which gets divided by a configurable 16-bit divisor, and the UART then samples the signal 16 times per bit period leading to the well-known maximum serial port bit rates of 1,843,200 / 16 / 1 = 115,200 1,843,200 / 16 / 2 = 57,600 1,843,200 / 16 / 3 = 38400 1,843,200 / 16 / 6 = 19,200, etc.
Peter Tirsek
2025-05-21 15:34:42 +0000 UTCI remember these days. Once I downloaded (or made an attempt to download) around 100MB in the later days of modems, and a family member decided at 98% to pick up the phone. Grr. For the idea, it was 2 hours of time wasted...
Sjoerd van Leent
2025-05-21 15:15:27 +0000 UTC
