Earlier this year a Japanese company called Planex Communications put a USB modem on sale on Amazon for about forty dollars. It is a small white plastic brick. It supports V.90 and V.92, peaks at 56 kilobits down and 33.6 up, and connects to a copper landline if you still have one. The headline on the coverage was half nostalgia and half disbelief, because you can buy a brand-new dial-up modem in 2026, but what you cannot buy back, fully, is the sound it makes.

The handshake is the part everyone over thirty-five remembers, even people who claim to have forgotten it. Long enough to time, if you wanted to. Dial tone, then a stuttered DTMF burst that was the phone number being dialled, then a single low carrier tone from the answering modem at the other end. After that, the conversation. Two short bursts of warbling that felt like both speakers were talking at once, then a sharp high-frequency screech, then a softer hashing sound that always seemed to be the part where the connection took. Then silence and you were online.

Oona Räisänen, a Finnish hacker and signal-processing enthusiast, drew a labelled spectrogram of the whole thing in 2012, and Popular Mechanics later walked through it second by second. The point her post made, and that almost everyone who has written about it since has repeated, is that the noise is not a side effect. The handshake was the negotiation. Two modems on a copper line had nowhere to talk except inside the audio band of the call itself, so they negotiated capabilities, line quality, and modulation in tones that any human picking up the phone could hear. There is a V.8 capability exchange near the start, a long V.34 training sequence (the part that sounds like a fax wheezing), a brief warble where both ends agree they can do V.90 or V.92, and a Digital Impairment Learning sequence near the end where the digital side measures the noise on the line. After the DIL, the speaker turned off and the data started.

The reason the sound stopped is that the negotiation moved off the line. Cable modems, DSL, fibre, 5G all carry their handshakes silently in the digital layer. There is no audio channel for them to leak into. Setup happens out of band, the way it does on every other modern protocol. You plug a router in and a green light comes on. The light does not encode anything you would call a conversation.

This is what gets nostalgia clips so often, I think. It is not just that dial-up was slower or that the squeal was funny. The sound was the only working connection most people of my generation ever had to the actual mechanism of going online. You could hear what the machines were doing. You could tell, by ear, when one of them was struggling. You could time, roughly, how long until the page would start arriving. None of that is true now. The work is silent and the work is somebody else's.

Gough's Tech Zone has been archiving V.90 and V.92 handshake recordings since the mid-2010s, partly out of affection and partly because most ISPs have shut their modem banks down and the upstream end of the connection is becoming hard to reach. There is a phrase he uses, the POTS-line apocalypse, for the gradual decommissioning of analog phone service worldwide. When the analog phones go, the digital end of a V.90 handshake stops being possible. The sound becomes uniquely an artefact of recordings.

Planex's modem, then, is not a modem in the way a 1999 modem was. It is a modem-shaped object that can still produce the sound, between two of itself, into a network that almost no longer wants it. You can buy it. You can plug it in. You can have, if you want, the audio of a connection nobody is waiting for at the other end.

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