

The sound of the dialup, pictured - randomdrake
http://windytan.blogspot.com/2012/11/the-sound-of-dialup-pictured.html

======
DrPhish
When I was growing up, my buddy's dad happened to be an old Berkley unix guru
greybeard mad scientist type who told great stories of dumpster diving and the
olden days. I was running a BBS at the time, and he told me stories of working
in a modem manufacturing facility in QC. According to him, they would whistle
into the receiver of each modem in order to test that it was at least
minimally operational. I tried this a number of times by dialing into my BBS
and got good enough to be able whistle up a 9600baud connection. I don't know
why, but I really relished getting that rush of static noise after connecting
successfully.

------
antirez
The blog is fantastic, really -> <http://windytan.blogspot.it/>

~~~
axelfreeman
I like it too. Thanks for sharing. :)

------
a_p
The audio file on wikimedia commons provides automatically transcribed closed
captioning that is unintentionally hilarious. The Portuguese subtitles include
"Tchaaaaahhh puaaaoooooaaahhhhh" and "sshhhhhhshshhhhhhh."
[http://commons.wikimedia.org/wiki/File:Dial_up_modem_noises....](http://commons.wikimedia.org/wiki/File:Dial_up_modem_noises.ogg)

~~~
a3_nm
Are you sure those were automatically transcribed?
[https://commons.wikimedia.org/w/index.php?title=TimedText:Di...](https://commons.wikimedia.org/w/index.php?title=TimedText:Dial_up_modem_noises.ogg.en.srt&action=history)
says they were uploaded by an anonymous user. I think this is a joke created
by a human.

------
js2
I started with a 300 bps modem (Novation AppleCat II, it could actually do
1200 half-duplex to another AppleCat II). From there a 2400 bps modem, then a
9600, then finally a 56k before I had ISDN, DSL, etc.

I remember the evolution in tones but never knew what they were till I took a
signaling class in college. One of the projects in that class was to build
visual transmitters. We'd stand outside a few hundred yards apart and see how
fast we could transmit a message to a partner. The trick to being fast was
encoding multiple bits in each symbol, but not so many you'd fumble around
grabbing the next symbol. I think my transmitter encoded 2 bits at a time (so
four symbols).

Aside, the Apple Cat II was a fascinating modem -
<http://www.jammed.com/~jwa/Machines/cat/>

~~~
alexkus
The early modems I had access to were 300/300 or 1200/75.

Ah! V.23.

The 75 baud backward channel of 1200/75 was good enough to keep up with typing
so it was my preferred speed when accessing various things remotely where I
never needed to send large amounts of text/data but had lots of data coming
back the other way.

------
jimzvz
What I never understood is why the modem plays this through its speakers
instead of some other tone that lets us know that it is connecting. Any
explanation?

~~~
teeray
From what I've understood it's so you can identify if the line is, in fact, a
modem. Easy to diagnose the issue when you hear "Mach Pizza, can I take your
order?" coming through the speaker

~~~
a3_nm
Agreed. I've already witnessed Windows making a modem call the fire brigade
emergency number (probably because it was confused about the country I was
in). Woops.

------
ajpiano
I wanted to see where in the spectrogram the sound was as it was playing, so I
threw together this quickie jsbin to make it happen:
<http://jsbin.com/amunug/10>

Useful for anyone else who wants to be able to match the sounds and pictures,
I hope!

~~~
isnotchicago
Your image wasn't loading for me, so I updated with the correct (for me) URL.
<http://jsbin.com/amunug/7>

~~~
ajpiano
After a bit of back and forth, here's a working one with a persistent image
link and the proper proportions <http://jsbin.com/amunug/17> :)

------
mech4bg
It worries/amazes me that along with all the nostalgia that this thread has
brought up, it's made me realize I can still remember parts of my 28.8k
modem's initialization string. AT&F&C1&D2 from memory.

Reading someone else's post about the Apple Cat II just reminded me of the
sheer joy of experimentation at the time. While what we have now was what we
were ultimately striving for and would have switched to in a heartbeat, I'm
glad for the experience I gained at the time. And I didn't know better so I
still loved it :)

I just want to know how I got my first BBS numbers - I was visiting NZ when I
got my first modem, and somehow got hold of some local numbers and then found
other BBSes from there... but how did I get the first one?

~~~
aidos
It was all word of mouth back then. I grew up in nz and while I didn't have a
modem back in the bbs days, my best friend did. I distinctly remember cycling
over to one of the bbs operators houses to pay him for extra access (he had
two lines). Quite magical times really.

------
nwh
Got a wave of nostalgia from that, except that the line tests at the end are
slightly different than the warbles my modem used to play. It's been years and
I can still remember the difference between a 28.8k and 56.6k connection
sound.

------
jdiez17
It's fascinating; what we would consider an ancient piece of technology
performs a wide variety of tricks to overcome the optimizations done by
telephone networks. I especially liked the part where they transmit data in
order to measure the status of the phone line.

~~~
wmf
These modems are from 1999 or later, so not exactly ancient. Now I'm wondering
if the limit to modem speeds in the 80s and 90s was encoding design or the
cost of DSPs to implement more advanced encodings.

~~~
Geee
I think it's mostly due to the fact that modems used just the audio bandwidth
of the telephone line, which is about 3 kHz (by design). This limits the
maximum speed, earlier versions probably had problems with transceiver
complexity.

------
yitchelle
Acoustic Couplers. The bane of my early childhood. When "real" modems came on
sale, it was like the heavens opens and angels sang. For those old enough, you
know what I am talking about. It really is a wonder that this type of
communications caught on at all when it started with acoustic couplers.

~~~
yuhong
Ah, the old Bell system and Carterfone, though to be honest people still used
these later on for things like payphones.

------
jgrahamc
The phone number dialed in this appears to be +1 570 234 0003.

~~~
nollidge
To reveal the magician's secret: the lower tone indicates the row on the phone
keypad, and the higher tone indicates the column. So on a keypad, the first
four digits 1-5-7-0 consecutively goes down the keypad's rows and alternate
between the first and second column, and you can see that same pattern in the
picture.

IOW, each digit plays a two-note chord indicating the row and column on the
keypad.

EDIT: <http://en.wikipedia.org/wiki/Telephone_keypad>

------
afandian
Brilliant. This is something I have wanted to know for many years.

------
UntitledNo4
Slightly related, Looper's Modem Song:
<http://www.youtube.com/watch?v=i3VzSv4ErEg>

------
quahada
A better way to picture a dial-up modem's sound is as a digital communication
constellation. Modems likely used BPSK, QPSK, 8-PSK, 16-QAM, etc modulations.
For a theoretical example, see
<http://en.wikipedia.org/wiki/Quadrature_amplitude_modulation>

~~~
quahada
Actually, a little research showed that a 56k modem uses PCM and PAM
modulation schemes: [http://www.eetimes.com/design/communications-
design/4018048/...](http://www.eetimes.com/design/communications-
design/4018048/An-Introduction-to-the-V-90-56K-Modem)

So primitive...

------
Eduard
The current diagram version is missing those funky sounds starting at 21.50
sec

------
codezero
I love the commentary added in the image, it makes the modems' negotiation
sound like a bragging competition.

------
hamxiaoz
Very nice graph, does anyone know which tool to generate such a graph?

~~~
barakm
The graph is a spectrogram: <http://en.wikipedia.org/wiki/Spectrogram>

You've probably seen one before in relation to music. However, since we're
dealing with computer-generated tones here, the spectrogram looks very very
sparse (few overtones). You can see patterns in music as well, just not as
clearly (because there's a lot more going on).

If you'd like to make your own, consider looking into GNU Octave
(<http://www.gnu.org/software/octave/>) or possibly Scilab, both of which are
free.

EDIT: I might add that Audacity can easily view the spectogram of a sound
file, but if you want to manipulate the signal programatically (filters and so
on; signal processing is a great subject), try the above.

------
kiallmacinnes
So - I've always wondered, but never looked into this..

Why does dial-up always sound the same? That clip is exactly how I remember my
modems sounding!

Edit: Hah, Scroll down Kiall, scroll down.

