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Phone phreaking audio archive
August 31, 2012 5:39 AM   Subscribe

Phone Trips - an audio archive of the Phone Phreaking community. Phone phreaking was the practice of hacking into phone systems and networks in order to explore these networks and their connections [1 2]. Many people first heard about the phenomenon in a 1971 Esquire article, Secrets of the Little Blue Box, which included input from Captain Crunch. Crunch discovered that you could access telephone networks by blowing a 2600 Hz tone, from a whistle given away free in cereal boxes, into telephone handsets. "Have you ever heard eight tandems stacked up?" asked Crunch in the interview. Well, now we can, thanks to a large audio archive of phone phreaking.

From the Esquire article:

"Listen," he says, his spirits somewhat cheered, "listen. What you are going to hear when I hang up is the sound of tandems unstacking. Layer after layer of tandems unstacking until there's nothing left of the stack, until it melts away into nothing. Cheep, cheep, cheep, cheep," he concludes, his voice descending to a whisper with each cheep.

He hangs up. The phone suddenly goes into four spasms: kachink cheep. Kachink cheep kachink cheep kachink cheep, and the complex connection has wiped itself out like the Cheshire cat's smile.


The archive contains links to Real Audio files, but you can also access mp3 versions of the same files via ftp://ftp.wideweb.com/GroupBell.

The sound of stacked tandems is in the file "Classic Tandem Stacking (January, 1975)" - see the file ftp://ftp.wideweb.com/GroupBell/Classtack1HQ.zip in the associated ftp directory.

Some previous: 1 2
posted by carter (29 comments total) 40 users marked this as a favorite

 
Ah, memories. I was able to read through these text files at an odd point in time, where they were still sitting around on BBSes, but few of the techniques were still technically relevant. It took me a good bit of time to learn that, though.

Truly this is an amazing piece of our shared technical history.
posted by odinsdream at 5:44 AM on August 31, 2012


I'm looking forward to this book, Phil interviewed a lot of primary sources here on both the phreaker and the telco side. His blog has some cool FOIA docs and other gems.
posted by These Premises Are Alarmed at 6:19 AM on August 31, 2012 [1 favorite]


Phone phreaking predated me; I didn't really develop any technical skills at all until well after the phone company had fixed the issues that made phreaking possible. But I'm old enough to understand the appeal.

You gotta realize, back then, it was hard to reach family and friends that were any distance away. Telephones were usually free to use locally, but as soon as you left your local exchange and went long distance, it became staggeringly expensive. I worked in retail for a number of years, and when asking people to hold, if they said they were long distance, you took care of them first, because it would cost them like a dollar a minute to sit there in silence... and dollars meant rather more in the 1980s.

You simply didn't call long distance except at Thanksgiving, Christmas, and for emergencies. Anytime but the holidays, the crackly, staticky sound of a long-distance call was occasion for dread, because it was going to be something serious, and probably a call you really didn't want to take.

And everyone knew the phone company was ripping us off. We knew it didn't need to be that expensive, and we resented Ma Bell very much. So, the phone phreakers were almost heroic, for anyone clued in enough to really hear about them. Putting one over on the phone company (note: THE phone company, there was only one) was canned justice, distilled righteousness. They were as abusive as monopolies always are, making goddamn sure that nothing like innovation threatened their business model, and taking something from them that was paid for by their overhead, not really adding extra costs, must have been fun. It was sure fun to read about.

Those systems were immensely complex, a product of oldschool telephone engineering. They were supremely reliable, and designed to do just one thing, connect calls from place to place, anywhere in the country, just by making a few sounds into to the receiver. If you think about it, that's pretty weird -- make a bunch of clicks on the lines, or some specific sounds, and the system would figure out how to route your call, would set up reservations all the way across the country, and connect you. And they did it with more sounds; they hid this from you, but the switches signaled each other on the same line that you'd be using for voice, a minute later.

The hackers were able to figure out these tones (how, I don't know, since they're normally masked from end-users), and could then just send commands along the wire. The phone company was using security through obscurity, assuming that nobody would ever think to send a 2600Hz tone down a voice line. So, by saving money and using the same channel for both commands and data, they exposed themselves to hackers sending their own commands. There was no authentication; the assumption was that anything sending command tones on a telephone had to be a switch. It couldn't possibly be, say, Jim Draper, wanting to call his buddies, long distance, for free.

As an aside, phone engineering, with all its stolid certainty and never-fail engineering, was diametrically opposed to the packetized networks we use today. Phone engineers wanted a guarantee that your call would be handled perfectly; network engineers are okay with best-effort and some dropouts, or perhaps even outright dropped connections. Voice isn't special, in their world, it's just more data, and it gets there, or it doesn't, and you try again. And, in exchange, they can pump vastly more data through the same wires, and can use those wires for any purpose, not just carrying voice. It's tremendously better, but the phone company (later, companies) did their absolute damndest to stop these dangerous new ideas. But they'd been so abusive for so long that when they started crying about how terrible modems were for their business, the politicians didn't just ignore them, they passed laws telling them to suck it up, sweetheart.

Somehow, I don't think a digital revolution could happen in America of 2012. I just can't imagine corporate interests being overridden to that degree anymore. And I think anyone like Jim Draper would end up in Guantanamo.
posted by Malor at 6:45 AM on August 31, 2012 [21 favorites]


Phone phreaking predated me; I didn't really develop any technical skills at all until well after the phone company had fixed the issues that made phreaking possible. But I'm old enough to understand the appeal.

I made a red box in 2001 expecting it not to work and the feeling I got when it did was complete exhilaration. Even if all I could fake was nickel drops (it took FOREVER to make a long distance call). One of the best nights in my life actually, walking around at 1 am looking for
a pay phone to test it out on.
posted by nathancaswell at 6:51 AM on August 31, 2012 [5 favorites]


Somehow, I don't think a digital revolution could happen in America of 2012. I just can't imagine corporate interests being overridden to that degree anymore. And I think anyone like Jim Draper would end up in Guantanamo.

This, exactly.

There was something magical about the confluence of events, technology, legislation, public awareness (or lack thereof), of that particular point in history.
posted by odinsdream at 6:59 AM on August 31, 2012 [1 favorite]


The end of multi-frequency (MF) phreaking in the lower 48 United States occurred on June 15, 2006, when the last exchange in the contiguous United States to use a "phreakable" MF-signalled trunk replaced the aging (yet still well kept) N2 carrier with a T1 carrier. (Wikipedia article on Phreaking)

I remember playing [some] box that a friend made in high school, in the mid-1990s. We went to a pay phone in a remote county park, and tried to trick the phone. Something wasn't quite right, as an operator came online and asked if we were using foreign coins. At least, that's how I remember the night going.
posted by filthy light thief at 7:26 AM on August 31, 2012


The dangers of in-band signalling.
posted by tommasz at 7:34 AM on August 31, 2012


I can't play the Real Audio files due to my firewall, so I went to YT to see if any of it was there. I still don't know, because I'm watching this video with Captain Crunch, which has this as part of the ominous description:
He also demonstrates an early auto-dialer Apple computer program -- loaded via audiocassette. He used this program to discover AT&T's remob ("remote observation") program that was used to tap civilian phone lines.
posted by DU at 7:37 AM on August 31, 2012


D'oh, this video.
posted by DU at 7:37 AM on August 31, 2012


the feeling I got when it did was complete exhilaration

Also, I needed a long distance number and didn't want to call my parents at 1 am so the only other long distance number I knew by heart was the phone number of my childhood friend that I had a MASSIVE falling out with in like 4th grade. So there you go, don't suddenly ignore your lifelong friend one day to hang out with the cool kids or else your parents may receive an illegal phone call 15 years later in the middle of the night. I HOPE YOU LEARNED YOUR LESSON LEE THEY WERE SO SLEEPY, SO SLEEPY.
posted by nathancaswell at 7:43 AM on August 31, 2012 [6 favorites]


Project MF is a living, breathing simulation of analog SF/MF telephone signaling just as it was used in the telephone network of the 1950s through the 1980s. It lets you "blue box" telephone calls just like the phone phreaks of yesteryear ... except that it's totally legal!
posted by frijole at 7:48 AM on August 31, 2012 [2 favorites]


Malor:The hackers were able to figure out these tones (how, I don't know, since they're normally masked from end-users), and could then just send commands along the wire.

At the transition point from relays to digital, starting in about 1976-77, unionized switching center technicians could either move to the new centralized hub ninety miles away, retire, or become cord-board and manual directory assistance operators. This was the functional equivalent of being demoted from jet aircraft pilot to hubcab polisher, with the added knowledge that the cord-board operators were next to be phased out.

I daresay there was some knowledgeable angst (and possible disgruntlement) involved with "figuring out" and sharing those tones, just sayin.
posted by halfbuckaroo at 8:03 AM on August 31, 2012 [3 favorites]


They were as abusive as monopolies always are, making goddamn sure that nothing like innovation threatened their business model

That's not really fair.
posted by downing street memo at 8:08 AM on August 31, 2012 [1 favorite]


A lot of the innovation and technological advances developed by Bell Laboratories were stifled or extremely slow to roll out because of one man: J. Edgar Hoover. Until his death in 1972, he wanted to be able to tap every phone in the United States at will, and he could.

Emergency military protocols overrode every other type of call connected by an operator. Commercial civilian communications were the lowest priority on the totem pole.
posted by halfbuckaroo at 8:26 AM on August 31, 2012


Pretty damn cool. At any rate the articles from The Bell Systems Technical Journal, notably Signaling Systems for Control of Telephone Switching from 1960 and In-Band Single-Frequency Signaling from 1954 and Notes on Distance Dialing from 1956 are all avalable on the web now so we can all see how not trivial it was to implement it and for phreaks to reverse-engineer it. Back then this shit wasn't computerized, in the above articles you can see bits of circuit diagrams to detect these tones. Not to mention that those journals are 100% industry jargon. It must have been like a foreign country.
posted by Ad hominem at 9:39 AM on August 31, 2012 [1 favorite]


The hackers were able to figure out these tones (how, I don't know, since they're normally masked from end-users), and could then just send commands along the wire. The phone company was using security through obscurity, assuming that nobody would ever think to send a 2600Hz tone down a voice line.

Wasn't even that obscure. Two articles, Signaling Systems for Control of Telephone Switching and In-Band Single-Frequency Signaling gave away the store.People read these articles and built electronics to generate the tones mentioned. Engineers wanting to brag, or communicate clearly with colleagues are not the best secret keepers.
posted by Ad hominem at 9:44 AM on August 31, 2012 [1 favorite]


I started phreaking in high school, which admittedly was the late 90's. In those pre-cellphone days of expensive long distance, it was a great way to stay in touch with friends and family. I ordered my chips from mouser, bought my tone dialer @ radio shack, swapped out the chip and away I went. I had $1, $.50, and $.25 tones in the quick-dial slots.

Just the other day I was cleaning out some stuff at my parents house and found the box where I bought out all the remaining tone dialers when local radio shack discontinued them for like $5 each. I've got like 7, lol, new in box!
posted by TomMelee at 9:51 AM on August 31, 2012 [1 favorite]


I had a pretty nice modified radio shack dialer . I had two crystals with a switch between them so I could still use DTMF, had a jack so you could plug in headphones to output to, made it a bit less nefarious looking using it on crowded city streets.

I used it a bunch but obviously you cant use it in your house. From home you need a diverter, there were also various RBOCs around that were less than dilligent with actualy checking credit cards, so if you could generate a CC# matching the checksum you could charge any calls you wanted. Also codez. I see people buying prepaid calling cards all the time, there must still be a brisk business in codes.
posted by Ad hominem at 10:15 AM on August 31, 2012


Man, this takes me back to the early 80's. I remember hand-scanning the 99xx ranges in local exchanges looking for loops, etc..
posted by mikelieman at 10:40 AM on August 31, 2012 [1 favorite]


I haven't read all the links, but it must be said that this phone phreaking was partially responsible for the PCs we use today.

One of Steve Wozniak's early hobbies was phone phreaking, and he was a friend of Captain Crunch (and even came close to getting arrested a few times). His interest expanded into other electronics, and finally microprocessors (a technology he thought, at first, had passed him by! He said this in a talk I once attended), which lead to founding Apple Computer.

Captain Crunch even wrote a cross assembler used in the development of Apple I and II.
posted by eye of newt at 1:13 PM on August 31, 2012 [1 favorite]


And everyone knew the phone company was ripping us off. We knew it didn't need to be that expensive, and we resented Ma Bell very much.

Well, I think they subsidized some damn fine local service with long distance rates. And hey, you could frickin' UNDERSTAND what people said. It was pretty amazing audio actually. Cell phones in my experience sound like shit, we're always stepping on each others sentence beginnings due to this bizarre lag (or maybe its some sort of shitty attempt to minimize background noise) but the market truly has spoken - people will gladly accept lesser quality audio quality in exchange for (almost) limitless mobility. I remember reading somewhere a long essay about the technological struggle between engineers - circuit-switching guys and packet-switching guys. That was fascinating stuff.
posted by quonsar II: smock fishpants and the temple of foon at 1:40 PM on August 31, 2012 [1 favorite]


One of Steve Wozniak's early hobbies was phone phreaking

Not only that, but in the Steve Jobs biography, it talks about how the original Jobs/Wozniak business arrangement was to design, manufacture and sell digital Blue Boxes.
posted by fungible at 3:24 PM on August 31, 2012 [1 favorite]


99xx

I miss the 99xx stuff. There was all kinds of neat things there. Switch identification was 9950 right?, as you mentioned loops, crazy test tones, numbers that simply played various exotic recorded messages like "service interruption due to storm" messages.

I "stumbled" across a loop maybe a year ago, with the telltail high/low tones , as well as various verizon test numbers. I'm scared to call that shit now though

Even the Telus ANAC that used to be at 416 981 0001 is dead now.
posted by Ad hominem at 6:41 PM on August 31, 2012


real audio :(

burn it with fire :( :(
posted by RTQP at 7:17 PM on August 31, 2012 [1 favorite]


I recently read "Loving Little Egypt" by Thomas McMahon, which took phone phreaking and set it in the time of Alexander Graham Bell and Thomas Edison. It's now a sort of double-nostalgia experience, since the 70s and 80s now seem as long ago as the 1920s.
posted by acrasis at 6:54 AM on September 1, 2012


About a decade ago I hung out with Draper at trance parties in the SF Bay Area. He was a trip, nearly exactly how I had imagined him being.
posted by krinklyfig at 11:22 PM on September 1, 2012


quonsar II: Well, I think they subsidized some damn fine local service with long distance rates. And hey, you could frickin' UNDERSTAND what people said. It was pretty amazing audio actually. Cell phones in my experience sound like shit, we're always stepping on each others sentence beginnings due to this bizarre lag (or maybe its some sort of shitty attempt to minimize background noise) but the market truly has spoken - people will gladly accept lesser quality audio quality in exchange for (almost) limitless mobility.

Sorry for the late reply, but it didn't occur to me until just now.

Analog telephone audio is only amazing compared to cellphones, which do indeed sound like crap. This is nothing inherent to analog or even to wires; it's purely a function of the bandwidth and codecs they use on cellphones. GSM, for instance, uses a notably shittier voice codec than CDMA, so that's why voice usually sounds kind of crap on AT&T and T-Mobile, where it's decent on Verizon.

But now that they've deployed 4G most places, we could be using enormously better codecs, stuff so good it sounded like someone was standing in the same room with you. Skype does this, to some degree, using a really superb homegrown codec, but still at fairly low bitrates. It sounds better than POTS (Plain Old Telephone Service), but not wildly so. Some of the voice chat programs like TeamSpeak allow you to choose decent codecs and high bitrates, so they also sound really, really good, much better than Skype, and WAY better than POTS. They tend to have latency issues, though, because they're mixing possibly dozens of separate voice streams.

All we really need, at this point, is reasonably wide deployment of some client program, and everyone's phone calls would sound bloody awesome. Lag and latency could be reduced, because much of that comes from the lousy voice codecs. But it wouldn't be eliminated, because some of the lag comes from the inherent crappiness of wireless networks, and we're not likely to escape that problem anytime soon.
posted by Malor at 1:17 PM on September 2, 2012 [2 favorites]


Good points Malor, I've wondered this myself in the whole cellular vs. data connections debate. Speaking of TS type VoiP, have you played with Mumble? Their codec makes TS and Skype look like early 90's cellular, and at intensely low bitrates. On my server, I' often have 6 people speaking simultaneously, and the most it's ever used was 27kbits.
posted by TomMelee at 6:23 PM on September 2, 2012


I haven't tried it, Tom. I'll have to check it out.... thanks for the pointer.
posted by Malor at 3:30 PM on September 3, 2012


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