In honor of the PRISM media frenzy, this week's Document of the Week concerns Greenstar, the AT&T toll fraud surveillance system that randomly monitored some 33 million American phone calls -- and recorded 1.5 million of them -- between 1964 and 1970.

Louis J. Rose had the scoop, on the front page of the St. Louis Post-Dispatch on February 2, 1975:

As I write in Exploding The Phone, "A single Greenstar unit would be connected to a hundred outgoing long-distance trunk lines and could simultaneously monitor five of them for fraud. [...] At its core, Greenstar looked for the presence of 2,600 Hz on a trunk line when it shouldn't be there. [...]  When Greenstar detected something unusual, it took an audacious next step: it recorded the telephone call.  With no warrant and with no warning to the people on the line, suspicious calls were silently preserved on spinning multitrack real-to-reel magnetic tapes." (p. 93).

In fact, when I interviewed Lou Rose in 2006 he told me that he had an actual Greenstar mag tape in storage someplace!  He had gotten it from the source who leaked the Greenstar information to him in the first place.  Unfortunately, when we talked, he was away from home and wasn't able to dig around and root it up for me. A pity, since that would have made a nice little bit of telephne memorabilia.

For more on Greenstar, check out:

• The full St. Louis Post-Dispatch article
• New York Times coverage of Bill Caming's testimony before Congress
• Transcript of the Greenstar Congressional hearings
• Lots of assorted articles and press coverage in the Exploding The Phone document database

Oh, and as AT&T attorney Bill Caming would want me to note, Greenstar was more properly referred to as "Toll Test Unit," since, as Caming said, "Greenstar just sounds illegal."  :-)

I recently posted about a searchable archive of about 800 historical phone phreaking documents that I used as research material for Exploding The Phone.  Even if you're really into this stuff, that's a lot of documents and it's hard to know where to begin.  So as a new feature for this blog I thought I'd start highlighting a new document every week.

This week's gem is the June 1972 Ramparts magazine article, "Regulating The Phone Company In Your Home" written by phone phreak Ray Oklahoma (a pseudonym).

Oklahoma's article was significant for a couple of reasons.  First, because it explained how to construct a "black box" -- basically, a device that would allow people to call you without their being charged for the call -- in way that made it so simple that anyone could do it.  (Check out the beautiful and friendly illustration below, for example.  You can click on it to get a slightly larger version.)

The second reason the article was significant was that Pacific Telephone and AT&T forced Ramparts to recall some 90,000 copies of the issue. As Ramparts editors wrote later, "Within a week American Telephone and Telegraph had achieved what the CIA, Pentagon, FBI and other targets of Ramparts’ journalism over the last ten years hadn’t been able to bring about: the nationwide suppression of this magazine." 

The black box article wasn't the first time Ramparts had run stories advocating telephone fraud, by the way. A few years earlier it published an article on the San Francisco Mime Troup titled "Ripping Off Ma Bell."  It's sort of classic for its over-the-top tone, to say nothing of its 1970-inspired color choices.  :-)

You can see the entire black box article here.  If you're still not satisfied, here are some links to additional Ramparts-related documents in the archives:

• "How The Phone Company Interrupted Our Service", Ramparts' version of what happened when AT&T got wind of the article
• Los Angeles Times and New York Times coverage of the dust-up

You can also view the complete archive of articles related to Ramparts here.

Ok, this isn't exactlty phone phreaking, but it does involve telephones, telephone security, and history.  John Young's Cryptome site just posted a formerly classified 1955 FBI/DOD document concerning a pretty interesting thing: a technique for bugging a room using an on-hook telephone by sending ultrasonic frequencies down the telephone line.  From the document:

The entire thing was classified TOP SECRET.  Apparently more modern telephones, such as the 500-series phone, were not vulnerable to this technique.  You can read the full details here.

Speaking of "more modern" phones, makes me think of this.

One of the biggest challenges I had in Exploding The Phone was to try to give some sense of what the old telephone network sounded like -- its "sonic landscape," if you will.  I did the best I could, but it's hard to do it justice.

Fortunately, a couple of people have created a pair of lovely guided tours of the sounds of the old network, so you can experience them for yourself.

The first one is from ElmerCat and is titled "Sounds of Long Distance Calls."  As he notes, "Today, every phone call you make sounds basically the same. However, back in the days of electromechanical switching, calls sounded quite different, depending on where you were calling, the type of local central office you were calling from, and the sometimes complicated route to get from one place to another..."

ElmerCat's web page gives a nice quick overview of old network sounds.  Phone phreak Evan Doorbell has one that is a bit longer and more detailed: