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Getting Dial-Up To Work Over VOIP Isn’t Always Easy

Por: Lewin Day
20 Diciembre 2024 at 03:00

Dial-up modems used to be the default way of accessing the Internet, but times have moved on. They’re now largely esoteric relics from a time gone by. With regular old phone lines rather hard to come by these days, [Peter Mount] decided to try getting a pair of dial-up modems working over VoIP instead.

The build started with a pair of Linksys PAP2T VoIP phone adapters, which were originally designed for hooking regular phones up to VoIP systems. He paired each US Robotics modem with a PAP2T, and then hooked both into a VoIP Private Branch Exchange which he set up using 3cx on a Raspberry Pi 3B+. The Pi also acted as a server for the modems to connect to. It took a lot of fiddly configuration steps, but he found success in the end. On YouTube, he demonstrates the setup—with that glorious modem sound—communicating successfully at a rate of 9600 baud.

It’s nice to see this vintage hardware communicating in a what is effectively a simulated world created entirely within modern hardware. We’ve seen similar projects before, like this attempt to get dial-up going over Discord. If you’re doing your own odd-ball screechy communications experiments, don’t hesitate to drop us a line!

Hackaday Links: November 24, 2024

25 Noviembre 2024 at 00:00
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We received belated word this week of the passage of Ward Christensen, who died unexpectedly back in October at the age of 78. If the name doesn’t ring a bell, that’s understandable, because the man behind the first computer BBS wasn’t much for the spotlight. Along with Randy Suess and in response to the Blizzard of ’78, which kept their Chicago computer club from meeting in person, Christensen created an electronic version of a community corkboard. Suess worked on the hardware while Christensen provided the software, leveraging his XMODEM file-sharing protocol. They dubbed their creation a “bulletin board system” and when the idea caught on, they happily shared their work so that other enthusiasts could build their own systems.

BBSs were the only show in town for a long time, and the happy little modem negotiation tones were like a doorbell you rang to get into a club where people understood your obsession. Perhaps it’s just the BBS nostalgia talking, but despite the functional similarities to today’s social media, the BBS experience seemed a lot more civilized. It’s not that people were much better behaved back then; any BBS regular can tell you there were plenty of jerks online then, too. But the general tone of BBS life was a little more sedate, probably due in part to the glacial pace of dial-up connections. Even at a screaming 2,400 baud, characters scrolled across your screen slower than you could read them, and that seemed to have a sedating effect on your passions. By the time someone’s opinion on the burning issues of the day had finally been painted on your monitor, you’d had a bit of time to digest it and perhaps cool down a bit before composing a reply. We still had our flame wars, of course, but it was like watching slow-motion warfare and the dynamic was completely different from today’s Matrix.

Speaking of yearning for a probably mythical Golden Age, Casio has announced a smart ring that looks like a miniature version of their classic sports chronograph wristwatch. The ring celebrates Casio’s 50th anniversary of making watches, and features a stainless steel case made by metal injection molding. The six-digit LCD is pretty limited in what it can display, and the ring doesn’t do much other than tell the time and date and sound alarms. So we’re not sure where the smarts are here, except for the looks, of course.

We got a tip recently on a series of really interesting videos that you might want to check out, especially if you’re into EMC simulations. Panire’s channel is chock full of videos showing how to use openEMS, the open-source electromagnetic field solver, with KiCad EDA software to simulate the RF properties of high-speed circuits. He’s got some in-depth videos on getting things set up plus some great tutorials on creating simulations that let you see how your PCB designs are radiating, allowing you to make changes and see the results right away. Very useful stuff, and pretty fun to look at, too.

Here at Hackaday, we get a surprising and disappointingly regular stream of projects that claim to finally have beaten the laws of thermodynamics. So the words “Perpetual Motion” are especially triggering to us, but we instantly put that aside when we saw the title card on this video about the Atmos Clock. No, it’s not perpetual motion, but since as the name suggests, being powered by atmospheric pressure and temperature changes, it’s about as close as you can get. We remember one of these beautiful timepieces on the mantle in our grandparents’ house, gifted to “Grampy” for years of faithful service by his employer. It was a delicate machine and fascinating to watch work, which it only briefly did once we grandkids got near it. Still, watching how the mechanism worked is pretty interesting stuff.

And finally, if you haven’t checked out The Analog, you really should. It’s a weekly newsletter written by our friend Mihir Shah and is full of interesting tidbits from the world of electronics and technology. This time around he gifted us with a video that looks inside optical sorting in food processing. You’ve probably seen these in action before, where cascades of objects — grapes in this case, obviously in a winery — are spread out on a high-speed conveyor belt under the watchful gaze of a computer vision system, which spots the bad grapes and yeets them into oblivion with a precisely controlled jet of compressed air. The mind boggles on the control loops needed to get the jet and the bad grape to meet up at just the right time so that good grapes stay in the game.

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