1512 lines
77 KiB
Plaintext
1512 lines
77 KiB
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PRIVATE LINE: A JOURNAL OF INQUIRY INTO THE
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TELEPHONE SYSTEM
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JUNE 1994: VOLUME 1, NUMBER 1
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-----------------------------------------------------
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TABLE OF CONTENTS
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1. General Information on private line
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2. The Front Cover and The Inside Front Cover
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3. The Editorial Page
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4. Telco Payphone Basics, Part 1
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5. The Post Pay Coin Line
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6. A Conversation With Motorola
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7. The GTE RTSS Phone
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8. California Toll Fraud Law
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9. Ad rates and Miscellaneous Information
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----------------------------------------------------
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1. General Info on private line: ISSN No. 1077-3487
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A. private line is published six times a year by Tom Farley. Copyright
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(c) 1994 FACTSHEET5 calls it "A great companion to 2600."
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B. Subscriptions: $24 a year for subscriber's in the U.S. $31 to Mexico
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and Canada. $44 overseas. Mailed first class or air rate .
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(1) Make checks or money orders payable to private line
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(2) A sample is four dollars. Back issues are five dollars apiece.
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The magazine is black and white. Double columns. Largely footnoted.
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(3) The mailing list is not available to anyone but me.
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C. Mailing address: 5150 Fair Oaks Blvd. #101-348, Carmichael, CA
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95608
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D. e-mail address: privateline@delphi.com
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E. Phone numbers: (916) 488-4231 (Voice) (916) 978-0810 (FAX)
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F. You may put this file up at any internet site or bulletin board that you
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wish. All I ask is that you reproduce the file it in its entirety and that
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you not sell a hardcopy version of the output.
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G. Comments and corrections are always welcome. I welcome
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submissions and I pay with subscriptions. You don't have to write in
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my style.
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NB: I am now accepting electronic related advertisements for the
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January, 1995 issue. This will be the first newsstand edition of private
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line. Distributed by Fine Print Distributors, Austin Texas. Ads are $75
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for a full page, $37.50 for a half page and $18.75 for a quarter page.
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No subscription required. Subscribers get free classifieds of 25 words
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or less.
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-------------------------------------------------------
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2. THE FRONT COVER AND THE INSIDE COVER
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The front cover artwork of this issue is from a 1965 Western Electric
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advertisement. It is an edge on photograph of five circuit boards that
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were used in the Number 1 ESS. I included the text of that ad in the
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inside cover page. It reads:
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"Electronic components by the thousands arrayed on circuit boards.
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These are at the heart of the Bell System's highly complex new
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Electronic Switching System. Now being built at Western Electric, a
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typical electronic system uses 160,000 diodes, 55,000 transistors,
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226,000 resistors, capacitors and similar components. Over the next
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few years, millions of American telephone users will benefit from the
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new services ESS will offer. But for Western Electric the coming of
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ESS presents a technical challenge equal to any we have faced in the 83
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years we have been a member of the Bell System. Not only do we stand
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behind the quality of the thousands of components, but we also make
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sure that each of these precision parts is assembled exactly. For the end
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requirement is that they work perfectly, each with each, and with every
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other of the billions of components in the nationwide Bell System
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communications network. We are able to do this job because, as
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members of the Bell System, we share its goals. Working together with
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people at Bell Telephone Laboratories, where ESS was developed,
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Western Electric people strive for perfection that enables your Bell
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telephone company to bring you the finest communications service in
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the world."
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-- Western Electric, Manufacturing & Supply Unit of the Bell System
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---------------------------------------------------------
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3. THE EDITORIAL PAGE
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private line
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a journal of inquiry into the telephone system
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Setting the Agenda; A Rambling Mission Statement From Your Editor
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The magazine 2600, The Hacker Quarterly, rekindled an interest in
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telephones that had laid dormant with me for over fifteen years. private
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line is an outlet for my interest in one the most marvelous, mysterious
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and elaborate inventions that man has ever invented: the telephone
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system. I hope that you find it a creative outlet for yourself as well. Let
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me tell you what I think are important goals for this magazine.
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1. This magazine will write for the beginner. There is a lack of good,
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clear information for the beginner in telephony. Most texts and articles
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assume a working knowledge of the fundamentals. That won't be the
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case here. Books and magazines about telephony often read as though
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one electrical engineer was writing to another. That's because they
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usually are. But who writes for the beginner? This magazine will.
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2. This magazine will turn articles into brochures. I want the
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information developed here to do more than sit in back issues. This
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material will go toward a series of beginner brochures on telephony.
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The magazine itself will be consecutively paged and indexed yearly.
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References will be given whenever possible.
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3. This magazine will encourage questions about the information
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presented. I want to be corrected if I make a mistake. I want people to
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feel free to contribute and to question and to challenge anything that
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appears here. The articles that I write are not the Last Word, rather, they
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are my best attempt to explain some difficult subjects. They are a
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starting point for a discussion of the topics involved. I have an ego as
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far as presentation and layout go. But I have no ego as far as being
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corrected.
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I hope you contribute. I welcome the comments of hackers, futurists,
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telecom people and technology buffs. Anyone who is interested in the
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telephone system is welcome to participate. I am really a beginner to
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telephony myself; let's learn together.
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Tom Farley
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privateline@delphi.com
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p.s. my handle is 'Sherman' and my callsign is KD6NSP
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------------------------------------------------------
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4. Telco Payphone Basics, Part 1
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A. Telephone Company Payphone Basics, Part 1
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1. A telco payphone is one that is owned and operated by the phone
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company that provides local telephone service: a former Bell company,
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GTE, General Telephone or another independent. Ownership aside,
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however, the one thing that makes a telco payphone a telco payphone is
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the fact that the machine's decision making ability resides in the phone
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system and not in the machine itself. This is different than a COCOT
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(customer owned, coin operated telephone) which makes most decisions
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on its own. When people can choose their local carrier, the so called
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alternate dial tone, ownership will be a less important criteria. You
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might have MCI as your telco, for example, instead of Pacific Bell.
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Let's start at the beginning.
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B. The Different Coin Lines
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2. There are two classes of coin phone service and three kinds of coin
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lines. The first class is post-pay, in which coins are deposited after a
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connection is made. Post-pay provides a dial tone without a deposit.
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The second class is pre pay in which a deposit is needed before a
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connection is set up. The three kinds of coin lines are called post-pay,
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for its operating method; coin first, which means that a deposit is needed
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to get a dial tone; and dial tone first, the pre-pay service that provides a
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dial tone without a deposit. Coin first is probably a defunct operating
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system. Dial tone first is by far the most common
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kind of coin line.
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C. What Is a Line?
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3. A line can be two things in telephony: a wire that carries a phone call
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or a channel in a wire or cable that carries a call. In either case, a line
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connects a coin phone or a customer phone to the switching office that
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provides local service. It is distinguished from a trunk which connects
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switching offices to each other or switching equipment within an office
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to each other. A line is almost always used in conjunction with local
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service, whereas trunks are thought of as providing long distance or toll
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service.
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4. In addition, a line can pass different voltages to signal different
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things. A trunk cannot. For example, a line can carry +48V DC to
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signal keypad inhibit, +130VDC to signal coin collect, and 75VAC to
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ring the phone. A trunk's voltage, however, remains the same. It must
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since the cable containing the trunk is usually carrying many calls at
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once; it is impossible to selectively control voltage within a channel in a
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common wire. Thus, lines and trunks often use different kinds of
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signals.
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5. A coin line is the circuit that connects a payphone to a central office or
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an end office. The line uses two copper wires, collectively called the
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twisted pair. There is nothing special about the wires themselves. There
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is no set
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of common wires that runs to all the payphones served by a central
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office. The phrase coin line is a designation. It indicates that the line
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needs special equipment at the central office to work. And since the
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equipment at the CO can vary, so can the kind of coin line.
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6. In addition, most telco coin lines are somewhat permanently
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connected to their switch. That is, the coin phone line is known to the
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central office to be a coin line. You would not, for example, have an
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unrestricted dial tone if you connected your lineman's handset to the
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wires. Instead, you would still be prompted for an initial deposit and
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you would still be asked by ACTS (1) to pay for long distance. At the
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very least, polarity would be reversed and long distance calling would
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be intercepted by an operator.
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7. Post-pay, coin first and dial tone first refer to the kind of coin line
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service that exists at a particular central office. The switching equipment
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and its accessories determine the kind of coin line service. Let's look at
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the two classes of lines more closely.
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D. The Metallic Line
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8. A line was originally defined as a "(w)ire or wires connecting stations
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in a telephone or telegraph system."(2) It often used as shorthand for
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transmission line. It is also called a VF or voice frequency line. And
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sometimes it's called an analog line. Two wires called a twisted pair or
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paired cable connect most phones to an end office or a connecting point
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to the end office. This is 19 to 26 gauge insulated wire. Look inside a
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service terminal to see twisted pair. The terminal is the point where your
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house or office phone line and the telco wiring connects, usually on an
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outside wall.(3) The phrase trunk line is often heard. That's not a
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combination of trunk and line, but, again, a reference to the trunk as a
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transmission line.
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9. A metallic line exists if there is a direct, physical connection with the
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end office and each subscriber's phone. Step by step offices, for
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example, may have each customer's twisted pair directly wired to a
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particular place in the switching frame. This metallic connection also
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exists with open wire, which uses copper wires strung from utility
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poles. In this case, twisted pair runs from the house or business to an
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aerial service terminal. Two uninsulated wires then go toward the end
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office, or more probably, a connecting point to the office. A metallic
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line, therefore, may change from one kind of wire to another. But it
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always keeps a copper connection of some sort for each subscriber
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phone or payphone.
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10. Both twisted pair or open wire help complete an electrical
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connection or circuit between the phone and the office. Circuit is often
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used interchangeably with line, creating more confusion than it should.
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Since this pair forms a circuit in the shape of a loop, it is often called the
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loop. The wires are also occasionally called conductors. That's because
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they conduct the electricity that operates the phone as well as carrying
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the conversation itself. The wires themselves are called tip and ring.
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Some assume that one wire is negatively charged and the other
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positively charged. Not so. Tip and ring do not refer to a pre-designated
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electrical state. As mentioned before, both tip and ring will have
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negative or positive voltages placed on them to signal different things.
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11. Not all lines, however, are based on a physical, metallic contact
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with their local switch. This is especially true with long distances
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between a phone and its end office. Resistance builds in a line as length
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increases. Signal strength goes down at the same time. Many means
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have been used to extend the length of the coin line or the subscriber line
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beyond, say, six miles.(4) At some point though, the conventional
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metallic line becomes unfeasible. Amplifiers or repeaters are needed to
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take the signal further. And a different operating system is needed to go
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along with this equipment. In these cases, the metallic pair may
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terminate at a connecting point to the central office. Special equipment
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then puts many, many subscriber lines on a single cable or a group of
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wires. The CO then provides a channel within the transmission line only
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when it detects that a phone has gone off hook. There is no longer a
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physical connection between each customer's twisted pair and the
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central office equipment. Let's look at the non-metallic line.
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E. The Non-Metallic Line
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12. The second definition of a line is that it is the communication
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channel connecting the subscriber to the local office. A line in this case
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represents an individual radio frequency that a phone call is placed on.
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These are called carrier frequencies. This differs from the voice
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frequency that carries the call in a normal line. This kind of line is also
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called carrier. Many, many conversations can be placed on a single
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wire through a process called multiplexing. (5)The most familiar
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example of multiplexing might be a cable TV line. A single wire or
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coaxial cable can carry dozens of television channels. The simplest form
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of multiplexing in telephony is called split carrier.
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Split carrier
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13. Split carrier uses a single twisted pair to carry more than one phone
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call. It is also called subscriber carrier. Some include this in a larger
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category called pair gain systems. It is not usually used to overcome
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long distances but rather to provide another line when there is no free
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twisted pair. In older buildings, for example, spare lines are frequently
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not available. In fact, you may be using split carrier now and not know
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it. "Whining sounds, echoes and slow dial tone response"(6) may
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indicate that your telephone line is being split and that your line is on the
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carrier side. Another sign might be if your modem does not work on
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your telephone line but does on your neighbor's. That's because the
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modem is using a carrier of its own to transmit information. The two are
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rarely compatible. A line on the carrier side is only a voice grade line.
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14. The voice frequency or VF channel is the normal, background
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path that carries a conversation on a twisted pair. You'll also hear the
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terms base band, voice channel and voice path. This is the first channel
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of two on split carrier. The second channel is created by transmitting a
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radio frequency at, say, a constant 100 kilohertz. That's a hundred
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thousand cycles per second. By comparison, the AM radio band begins
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at about 540 kilohertz. The signal of the second line is impressed on the
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steady carrier frequency. This causes the carrier signal to move up and
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down or modulate according to the changes in speech. So, two
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channels are now on one line. One conversation doesn't affect the other
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because you can't hear radio frequencies unaided. You now have a
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carrier line and not a voice frequency line. Subscriber carrier needs
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special equipment. I doubt that any coin phone uses this technique
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because of the number of voltage driven signals that must pass down the
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line. Never-the-less, some telcos may use split carrier for a public
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phone instead of a party line in rural areas. Perhaps. Let's look at more
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complicated multiplexing schemes. Again, these are examples of non-
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metallic lines.
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Analog multiplexing
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15. Both split carrier and voice frequency lines use analog signals.
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That's because normal speech, music and tones are all analog signals,
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once they're on the phone line. They are analogs, electrical
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representations of speech.(7) They are not altered or converted to a
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digital form. In other words, routine traffic in the local loop. Analog
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multiplex systems are used primarily for trunk traffic, that is, handling
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calls between switching offices. Analog carrier or N carrier is rarely
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used in the local loop. So, I'll discuss it more in the section on trunks.
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Some multi-channel analog systems do tie a customer's phone to its
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local switch but I have not found much information on them.
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Specialized equipment would be needed for coin phones; installed at the
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point where the multiplexer connects to the twisted pairs. This is needed
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to translate payphone signals from the central office to the voltages that
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control the phone. As I mentioned before, a channel in a cable cannot
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handle different kinds of direct current signaling. But twisted pair can.
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Hence, a need for an interface.
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16. It seems that most telcos decided that if they were going to install a
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carrier system for the local loop, they were going to use digital
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techniques. Both digital and analog multiplex systems use amplifiers or
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repeaters to keep signal strength up over long distances. Even so,
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analog signals degrade with distance. But digital signals remain stable
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for the length of their trip. That's because they are not an electrical
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representation of speech but a mathematical or numerical
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representation.
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Digital multiplexing
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17. You've probably seen a sine wave of an analog signal. It's a rise
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and fall pattern. By plotting its coordinates on graph paper, you know,
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C-3, B-4, A-2 and so on, we can record its shape in a numerical or
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digital form. And the more points we plot the more accurate the record
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becomes. Digitizing produces its plots by instantaneously measuring
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the ups and downs of signal strength. In T1, a signal's strength is
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measured or sampled two things: 1), the strength level itself and 2), the
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time at which it occurs. These two measurements or electrical plots are
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converted to binary numbers or bits. An eight bit group makes up a
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byte. Blocks and blocks of these fast moving digits then represent
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speech.
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18. Sampling takes a lot of measurements. But it is not continuous,
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even at eight thousand times a second. There are always small gaps.
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These breaks and blocks differ an analog signal from a digital one. A
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digital signal is made up of discrete units whereas an analog signal is a
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continuous unit. Built in error checking and uniform rules for encoding
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and decoding enables digitizing to faithfully reproduce a signal over
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thousands of miles. Fike gives some good examples in "Understanding
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Telephone Electronics." A digital carrier system makes the most sense
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when it ties into a digital central office. This saves the step of converting
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digital signals back to the analog ones that a simple end office can deal
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with.
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19. T1 or T carrier is the most common form of digital transmission
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used in the local loop. T1 is used primarily for trunks but it also
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provides tens of thousands of local lines to central offices and remote
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switches. This system converts the normal analog signal of a subscriber
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pair into a digital signal The signal is abbreviated as DS. A typical digital
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multiplex system might be Western Electric's SLC-96. (Subscriber loop
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carrier, version 96) It can accept 96 local subscriber lines. But only five
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wires may run to the distant office since the signals are multiplexed.
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We'll look at how it interfaces with the twisted pairs of the local loop in
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||
|
the discussion of the local switch.
|
||
|
|
||
|
F. The Local Switch
|
||
|
|
||
|
20. The kind of coin line service provided usually depends on the
|
||
|
equipment installed at the local switch. The type of switch itself is often
|
||
|
less of a concern than the options that go with it. Post-pay operation, for
|
||
|
example, usually depends on an end office with step by step switching
|
||
|
equipment. But step by step can be converted to pre-pay. On the other
|
||
|
hand, most crossbar switches and all electronic switches have been
|
||
|
configured for pre-pay service already.
|
||
|
|
||
|
21. Most central offices controlling payphones need the hardware that
|
||
|
enables automated coin toll service (ACTS).This is a system wide
|
||
|
program that handles most long distance calls from payphones. It's
|
||
|
what you get when you dial a 1+ call from most of the country. The Bell
|
||
|
System designed this program in the late 1970's for use by all the
|
||
|
regional Bell companies as well as subscribing independents.(9) Calling
|
||
|
card service was developed a few years later.(10) This required
|
||
|
additional equipment. Not having this equipment means that a particular
|
||
|
CO may not provide coin line service. This is why you'll often see
|
||
|
payphones in a town grouped to a certain prefix. It's a sign that that
|
||
|
exchange has had certain hardware installed. In addition, the kind of
|
||
|
trunk lines and local lines that the CO connects to will also influence the
|
||
|
way that an office is configured.
|
||
|
|
||
|
22. I'm not sure if it's profitable for me to spend much time discussing
|
||
|
individual switches. Many, many books have been written on them and
|
||
|
their variants.(11) Comparatively little has been spent on discussing step
|
||
|
by step offices or switches below
|
||
|
the central office. So, I'll do that. The discussion of the individual coin
|
||
|
line may give more information an a particular switch. The post-pay
|
||
|
section, for example, deals with the community dial office in detail.
|
||
|
We'll look at it in general here and then mention other end offices.
|
||
|
|
||
|
|
||
|
G. The End Office
|
||
|
|
||
|
23. The end office is your local switch, the one that your subscriber line
|
||
|
or coin line is first tied to. It is at the bottom of the switching hierarchy,
|
||
|
a so called class five office. This is usually a central office but not
|
||
|
always. Many, many rural communities are served instead by a
|
||
|
community dial office or CDO. These are mostly step by switches,
|
||
|
serving far fewer lines than a normal central office handles. Slightly
|
||
|
closer communities may be served by a digital switch called a remote.
|
||
|
The CDO depends on a central office that can be quite a distance away.
|
||
|
They are usually connected by an analog carrier or T1 to the central
|
||
|
office. Most CDO's don't have trunks to the outside world. Long
|
||
|
distance service needs to go out through the central office. A CDO may
|
||
|
not generate its own dial tone. But it does generate the power necessary
|
||
|
for the local phones to work. Some CDO's are called package offices.
|
||
|
|
||
|
24. Package offices seem to refer to a particular switching arrangement,
|
||
|
particularly the No.5 Crossbar package community dial office.(12) This
|
||
|
was a system of trunks and hardware that retrofitted certain CDO's. The
|
||
|
dial office had to use the Number 5 crossbar as its central office switch.
|
||
|
This package brought many features of the number 5 to rural areas.
|
||
|
This was an expensive arrangement. These offices had to have enough
|
||
|
traffic and revenue to justify it. I expect that they have probably been
|
||
|
replaced in former Bell System country, since greater revenue drives
|
||
|
quicker upgrading. I would welcome hearing about any crossbars that
|
||
|
are still in operation. So, what kind of CDO took its place?
|
||
|
|
||
|
H. The remote switching system
|
||
|
|
||
|
25. The RSS No. 10 or Remote Switching System was the Bell
|
||
|
System's answer to improve rural service in about 10% of their outstate
|
||
|
CDO's.(13) A subscriber' s line connected to the RSS. The RSS uses
|
||
|
T1 to connect with an electronic office or ESS as far as 175 miles away.
|
||
|
They were originally configured to work with the No.1ESS and then the
|
||
|
1AESS. Most but not all of these older CO's have been retired. An
|
||
|
electronic switch, the RSS No.10 shares much of the same architecture
|
||
|
as its bigger brothers. Even, so, the CO controlling the switch has to
|
||
|
have certain hardware installed in order to work with it.
|
||
|
|
||
|
26. Wire pairs from the local loop would terminate inside a small
|
||
|
building containing a remote switch and the T1 carrier facility. The RSS
|
||
|
provides power to the loop and the T1 equipment sends the subscriber
|
||
|
traffic to the ESS office. A payphone would be enabled by a special
|
||
|
circuit board inside the T1 service cabinet. This plug in module
|
||
|
provides the proper interface to the switch.(14) The RSS would provide
|
||
|
the power necessary to implement all the voltages needed for signaling
|
||
|
the coin phone. One interesting aspect is that a TSPS operator could
|
||
|
handle a coin call from as much as thousand miles away, since it is the
|
||
|
distance from the CO to the operator that is now a controlling factor, and
|
||
|
not the distance from the payphone to the central office. Another remote
|
||
|
switch seems to be the DMS-10.
|
||
|
|
||
|
27. The DMS-10 switching system is a Northern Telecom product
|
||
|
designed to Bell System standards. It handles 200 to 6000 lines. Why
|
||
|
did Bell use an NT product? Cost. The DMS-10 is a small digital
|
||
|
switch. It can provide some custom calling services that may generate a
|
||
|
little more revenue than a normal rural switch. This may help the telco
|
||
|
generate a faster return on its money in a low traffic area. The ultimate
|
||
|
remote switch is probably the No. 5A Remote Switching Module.
|
||
|
|
||
|
28. The No. 5A Remote Switching Module or RSM, is, as you've
|
||
|
guessed, the specific remote switch for the No.5ESS. T-1 or fiber optic
|
||
|
takes the local traffic to the No. 5. The big difference here is that this
|
||
|
switch can pass long distance calls to the network without going
|
||
|
through the central office first. A CDO doesn't normally have trunks to
|
||
|
the outside world. With this CDO, however, the trunks are so arranged
|
||
|
that long distance traffic may go directly to a toll office and not first to
|
||
|
the CO. The term CDO is applied less and less as the years go on.
|
||
|
People often just call these switches remotes or modules.
|
||
|
|
||
|
29. It's impossible in an introduction to cover all the possible
|
||
|
configurations of the end office. There are many, many kinds of
|
||
|
arrangements. The most important thing to remember is the dependence
|
||
|
of the CDO or remote switch on the central office. Microwave radio
|
||
|
may be used in some areas to connect to a central office. A cellular
|
||
|
phone site is also an end office. It provides dial tone. I know that
|
||
|
Ericksson digital switches have been installed in many Motorola built
|
||
|
cell sites.
|
||
|
|
||
|
I. A few thoughts on step by step
|
||
|
|
||
|
30. Step by step switching is still with us. And probably for a little
|
||
|
longer. In fact, step by step may outlast crossbar, a different kind of
|
||
|
switching system deemed superior to step by step, or SXS as it's
|
||
|
sometimes abbreviated. Apparently, the Bell System choice for SXS
|
||
|
was Western Electric's No.355A. In 1974, step by step was used by the
|
||
|
Bell System for 22 million phone lines, one half million of which were
|
||
|
coin lines.(15) By 1980, 15 million lines were still in service. Step by
|
||
|
step was to be phased out by 1990.(16) That would have eliminated the
|
||
|
800 central offices with SXS in ten years. Does anyone have an updated
|
||
|
census of the regional holding companies, the former baby bells? The
|
||
|
story outside of the former Bell System is very different.
|
||
|
|
||
|
31. Telephony magazine used to publish a directory and buyers' guide
|
||
|
that was invaluable. It was a roster of the non-Bell operating
|
||
|
companies, a state by state guide to the independents, including GTE. It
|
||
|
list thousands and thousands of exchanges with step by step. The last
|
||
|
one I have is from 1987. Very few crossbars are noted in the West. I
|
||
|
understand that Automatic Electric did not make a crossbar. GTE
|
||
|
supposedly relied on makers like International Telephone and Telegraph
|
||
|
(ITT) to supply one when needed. It would have made sense for A.E.
|
||
|
to concentrate making step by step equipment. It's well suited to the
|
||
|
small towns that independent phone companies catered to. Step by step
|
||
|
offices probably have more add on equipment than any other. They need
|
||
|
it to fit in with the increasingly digital world.
|
||
|
|
||
|
32. A good example are touch tones. An SXS office couldn't process
|
||
|
them before, say, the mid 1960's. Now each office must. But step by
|
||
|
step manufactured after this time would have the right circuitry built in.
|
||
|
Coin service is another problem. Converting an office to dial tone first
|
||
|
was costly. And as coin phone signaling changes so must the CO. More
|
||
|
add on equipment needed. Want to implement ACTS? 911? Getting an
|
||
|
electro-mechanical office to implement these features is quite a task. And
|
||
|
while the telcos may want to put in custom calling everywhere, they
|
||
|
have many problems with step by step. Trunking is another matter, too.
|
||
|
Common channel signaling is seemingly bypassed, ignored or badly
|
||
|
implemented throughout thousands of miles of step by step country.
|
||
|
Not all exchanges, after all, have the enabling hardware to do System 7.
|
||
|
I'll cover this more in the next issue.
|
||
|
|
||
|
It's my experience that the most fun with the phone system comes at the
|
||
|
outer edges of it. There are as many hidden doors and gates there as
|
||
|
there are in Alice's Wonderland. But where do they lead? In the next
|
||
|
issue I will continue this discussion on basics. I'll try to cover trunks in
|
||
|
general, some terms on signaling, and the role of the operator and
|
||
|
TSPS.
|
||
|
|
||
|
J. References
|
||
|
|
||
|
(1) Automated coin toll service, or a derivative thereof, is the automated
|
||
|
operator that you get when dialing a 1+ call from most telco payphones.
|
||
|
For instance, if you dial, say, 1+(916) 213-9999 (an imaginary
|
||
|
number), a computer generated voice will come on the line to tell you
|
||
|
how much to deposit. You then hang up. You'll get a good insight into
|
||
|
the rates charged and the kind of coin service an area provides by dialing
|
||
|
the same number from different payphones in different areas. Do the
|
||
|
same with COCOTs. Listen for switch sounds in the background. You
|
||
|
may even be connected to a billable, long distance number without being
|
||
|
charged. That shouldn't happen. But it does sometimes. As Goldstein
|
||
|
says, "Anything is possible." My advice? Go rural. And go GTE.
|
||
|
|
||
|
(2) Douglas-Young, John. "Illustrated Encyclopedic Dictionary of
|
||
|
Electronics. "West Nyak, Parker. 1981. 335 Out of print but worth
|
||
|
looking for. This hardback is a good, one volume dictionary of
|
||
|
electronics. The section on electro-acoustics is great. His wife is Carol
|
||
|
Young who is the author of the readily available "New Penguin
|
||
|
Dictionary." This book, unfortunately, is much harder to understand
|
||
|
and less complete.
|
||
|
|
||
|
(3) Martin, John T."Chilton's Guide to Telephone Installation and
|
||
|
Repair." Radnor, Chilton Book Company. 1985. 5 A great how-to
|
||
|
book. I'm not sure if this edition is still in print but a revised version
|
||
|
should be.
|
||
|
|
||
|
(4) Among others, Schillio, Robert F. 'A Circuit That Stretches Coin
|
||
|
Telephone Service' Bell Laboratories Record. 51:4 (April 1973) 120.
|
||
|
Don't write off these early articles. They provide many clues as to why
|
||
|
things were done in a certain way, even if a particular piece of
|
||
|
equipment is no longer in service or a practice discontinued.
|
||
|
|
||
|
(5) Fike, John L. and George E. Friend. "Understanding Telephone
|
||
|
Electronics". 2d ed. Carmel, SAMS. 1990 16. Now in its third edition,
|
||
|
this book is widely available. You should buy this book. It assumes a
|
||
|
working knowledge of electronics. A beginner can push through most
|
||
|
of it with dedication. The second edition, however, has only a two page
|
||
|
index for a 284 page technical work.
|
||
|
|
||
|
(6) Martin, 53
|
||
|
|
||
|
(7) Strangely, I've seen a normal analog signal referred to as an AC
|
||
|
signal. And tones are often called AC signals. Yet, the only true AC
|
||
|
signal used is the voltage that rings the phone. How can a DTMF pad
|
||
|
use AC signaling when only DC voltage is present? Does AC really
|
||
|
refer, instead, to the shape of an alternating current waveform? An
|
||
|
alternating current is in the shape of a sine wave. Does this explain AC
|
||
|
signaling?
|
||
|
|
||
|
(8) Rey, R.F., ed. "Engineering and Operations in the Bell System". 2d
|
||
|
ed. Murray Hills, N.J. AT&T Bell Laboratories. 1983 373
|
||
|
|
||
|
(9) Staehler, R.E. and W.S. Hayward. Jr. 'Traffic Service Position
|
||
|
System No. 1, Recent Developments: An Overview' The Bell System
|
||
|
Technical Journal. 58:6 (July --August 1979) 111 Tough article but lots
|
||
|
of interesting details. Find a place you can check this out for a week; it's
|
||
|
really too long for photocopying but too essential to let go.
|
||
|
|
||
|
(10) Confalone, B.E., B.W. Rogers and R.J. Thornberry, Jr. 'Calling
|
||
|
Card Service--TSPS Hardware, Software, and Signaling
|
||
|
Implementation' The Bell System Technical Journal. 61:7 (September,
|
||
|
1982) 1676 Another essential. Find a corresponding article in the Bell
|
||
|
System Record if you find the B.S.T.J. too intimidating.
|
||
|
|
||
|
(11) Fike gives a good, basic description of switches. If you want to
|
||
|
bury yourself in the subject then check out G.E Schindler,ed.
|
||
|
"Engineering and Operations in the Bell System: Switching Technology:
|
||
|
1925 -- 1975." Murray Hills, Bell Laboratories. 1982. Or, if you want
|
||
|
something practical, read Agent Steal 'Central Office Operations' 2600:
|
||
|
The Hacker Quarterly. 7:4 (Winter, 1990) 12--21
|
||
|
|
||
|
(12) Schluttenhofer, R.A.'Two-Way Trunks For Package Offices' Bell
|
||
|
Laboratories Record (November, 1965) 402
|
||
|
|
||
|
(13) Sevcik, Richard W. and D. Paul Smith. 'Custom calling comes to
|
||
|
Clarksville (upstate New York)' Bell Laboratories Record. 58:2
|
||
|
(February, 1980) 63. Fascinating article about a little known subject, the
|
||
|
Remote Switching System.
|
||
|
|
||
|
(14) Some may contend that the T1 line is a trunk in this situation and
|
||
|
not a collection of subscriber lines. A trunk, after all, is a circuit
|
||
|
between switches. They are partially correct. A remote unit is not a fully
|
||
|
functional switch. It cannot operate without the central office. It may not
|
||
|
generate its own dial tone. It can be viewed as an extension of the CO
|
||
|
and not as an independent office. A PBX is also a switch. But its lines
|
||
|
to the CO are treated as lines and not trunks. The PBX is not functional
|
||
|
without certain central office features. It is not able , for example, to
|
||
|
pass long distance traffic to the world without the CO. Line and trunk
|
||
|
are often used interchangeably in a discussion of traffic between the
|
||
|
CDO and the central office.
|
||
|
|
||
|
(15) Peterson, Gerald H. "Improving Coin Service For Step-by-Step".
|
||
|
Bell Laboratories Record (February 1974) 41
|
||
|
|
||
|
(16)Rey, 735
|
||
|
|
||
|
-------------------------------------------
|
||
|
|
||
|
|
||
|
5. THE POST PAY COIN LINE
|
||
|
|
||
|
A. Introduction to Post-pay
|
||
|
|
||
|
1. Post-pay coin phones still exist in many rural communities. Little
|
||
|
towns like Jordan Valley, Oregon or Buhl, Idaho are typical. These
|
||
|
phones quite often still take a dime for a local call. Their operation is
|
||
|
simple. You lift the handset. The central office returns a dial tone. You
|
||
|
dial your number. The payphone shorts out the transmitter and the
|
||
|
keypad when your party answers. You now have a few seconds to put
|
||
|
in your dime. This frees up the transmitter so that you can talk. Coins
|
||
|
are not returned unless rejected. A lack of coin return isn't a problem
|
||
|
since you don't put in any money unless your call goes through. You
|
||
|
are often timed out after ten seconds or so if no money is deposited.
|
||
|
You can call the operator without a dime and in most cases 911.
|
||
|
Pranking is supposed to be a problem. Most of the towns I have been in
|
||
|
with post pay, however, have only one or two public phones to begin
|
||
|
with. You would probably be spotted easily if pranking was your
|
||
|
hobby. Post-pay is a nice system. Let's look at it further.
|
||
|
|
||
|
B. History of post-pay
|
||
|
|
||
|
2. The debate over providing post-pay or pre-pay coin service began
|
||
|
after the first installation of a non-attended coin phone in 1899.(1) Coin
|
||
|
first operation was more complex since it had to allow for coin return in
|
||
|
case a call did not go through. The coin phone and the central office
|
||
|
would also need more equipment. Post-pay was simpler but it took up
|
||
|
more of the operator's time. She frequently had to wait until the caller
|
||
|
found the right change so that she could then connect the call. With coin
|
||
|
first, however, the initial deposit was made before the operator came on
|
||
|
the line. The argument against coin first was more serious than
|
||
|
monetary: an operator could not be raised in an emergency without a
|
||
|
deposit. The debate did not last long. Operator time was too valuable to
|
||
|
waste. "(T)raffic holding-time savings"(2) pushed public safety
|
||
|
concerns aside. Fagen contends that from 1906 the Bell System
|
||
|
concentrated on providing coin first, pre-pay operation. Schindler,
|
||
|
however, points out that panel switching systems in the twenties
|
||
|
allowed for dial tone first and coin less calls to "operators, service
|
||
|
codes, and selected 'official numbers'." In any case, coin first or pre-
|
||
|
pay became the rule and the simpler, slower post-pay became the
|
||
|
exception.(3)
|
||
|
|
||
|
C. Post-pay today
|
||
|
|
||
|
3. Post-pay has survived at the outer edges of the phone system, in
|
||
|
little towns and distant villages. It has been that way for a long time.
|
||
|
Rey contends that post-pay operation was chosen for rural service
|
||
|
because of the "long distance between the local community dial office
|
||
|
and the resultant large cost of returning coins on unreturned calls."(4)
|
||
|
This is confusing. Returning coins is not terribly expensive by itself.
|
||
|
Post pay coin phones, for example, do return coins if a coin is invalid.
|
||
|
But pre-pay equipment is more costly than pre-pay. Post-pay is cheap to
|
||
|
install and maintain. It is compatible with the switching equipment at the
|
||
|
end office. As stated before, a payphone is dependent on the equipment
|
||
|
it is tied to. Most post-pay phones are not directly wired to a full
|
||
|
featured central office with a modern switch. They are instead first
|
||
|
connected to a simple CDO.
|
||
|
|
||
|
D. The community dial office
|
||
|
|
||
|
4. A community dial office is an end office that serves a few dozen lines
|
||
|
to perhaps 2000 lines. The last census of the Bell System in 1983
|
||
|
revealed 3,700 of these offices, more than any other kind of switch.(5)
|
||
|
A CDO is a step below the central office in rank and relies on the CO for
|
||
|
many things. It may not, for example, generate its own dial tone. In
|
||
|
many ways the end office acts as a remotely controlled switch. The
|
||
|
switching equipment itself is often the simple but reliable step by step.
|
||
|
Rey predicted that the now defunct Bell System would replace all
|
||
|
CDO's serving under step by step control by 1990. Perhaps the regional
|
||
|
companies did. GTE and other independent phone companies certainly
|
||
|
have not.
|
||
|
|
||
|
5. Community dial offices were first installed in the late 1920's when
|
||
|
direct dialing began replacing operator connected calls. CDO's were
|
||
|
widely deployed over the next forty years. They provided the backbone
|
||
|
of local switching in rural America, or outstate as Bell System lingo
|
||
|
used to put it. We'll look at post-pay in the context of a CDO. But not
|
||
|
all CDO's have post-pay. Many, many of the newer CDO's have pre-
|
||
|
pay service, especially the ones owned by the former bell companies.
|
||
|
Post-pay coin service was a part of CDO design since the beginning.(6)
|
||
|
But the real definition of a CDO is that it relies on a central office for
|
||
|
many functions, not that it provides post-pay. The reason that a CDO
|
||
|
has post-pay is because, usually, the low volume of calls. Such light
|
||
|
traffic might never justify the more expensive pre-pay. And coin
|
||
|
service, like regular subscriber service, is always more expensive in
|
||
|
rural America.
|
||
|
|
||
|
E. The subscriber loop network
|
||
|
|
||
|
6. A post-pay coin phone might be three to eight miles from the dial
|
||
|
office, however, the central office might be dozens and dozens of miles
|
||
|
away and the operator several hundred miles away. Some CDO's and
|
||
|
remotes handle local calls without first going to a central office. But
|
||
|
some may route a call out to the central office and then back through the
|
||
|
CDO. Once the connection is set up the call may be dropped back to the
|
||
|
local switch, freeing up the channel to the central office. This service
|
||
|
requires repeaters, line extenders, extra cable, miles of additional poles
|
||
|
and increased maintenance. Remote payphone lines need additional
|
||
|
equipment on top of that required for routine service. The small number
|
||
|
of coin calls near a community dial office might never justify pre-pay
|
||
|
service. As we will see, a relay to place reverse polarity may be all that's
|
||
|
needed at the CDO. A post-pay line presents nothing special to the dial
|
||
|
office. It is wired to the switching frame along with the other flat rate
|
||
|
phone lines. There are, however, trunking arrangements that have or
|
||
|
had to do with post-pay.
|
||
|
|
||
|
F. Post-pay trunks
|
||
|
|
||
|
7. Much of what is written about CDO's continues the uncertainty over
|
||
|
what is a trunk. Different writers at different times use both terms. This
|
||
|
is unfortunate but not surprising; the line from a CO to a CDO is a
|
||
|
hybrid. Let's use the word trunk for now. So, when talking about the
|
||
|
CDO we have the following: 1) a trunk from the CDO to the central
|
||
|
office, 2) a trunk from the CO to the a non TSPS operator, or, 3) a very
|
||
|
long trunk to a TSPS operator. Signals may be passed on the voice path
|
||
|
or on a data circuit. The thousands of CDO's and the dozens of possible
|
||
|
trunk configurations in rural America result in the greatest hope for the
|
||
|
trunk hopping telephone enthusiast; many of these trunks are still
|
||
|
controlled by tones and not digital signals. I'll introduce trunks in the
|
||
|
next issue when I finish up the discussion on basics. For now, let's
|
||
|
look at what you might find in former Bell System territory. I do not
|
||
|
know enough to comment on a GTE system, although the last two post
|
||
|
pay phones I used were both in independent areas.(7)
|
||
|
|
||
|
Post-pay and RTA
|
||
|
|
||
|
8. Coin trunks are usually provided between the CDO and the central
|
||
|
office to handle coin traffic. A trunking arrangement must also handle
|
||
|
the coin traffic between the CDO and the operator position. This
|
||
|
enables the operator in most cases to know that they are handling a
|
||
|
post-pay call. The traffic service position system (TSPS) was given
|
||
|
many new features in 1979. One important feature was the remote
|
||
|
trunking arrangement or RTA.(8) This was an expensive and
|
||
|
complicated system of trunks designed to bring the benefits of TSPS to
|
||
|
rural areas. A full service operator could now handle rural calls a
|
||
|
thousand miles away. Enabling hardware was installed in dozens of
|
||
|
rural or outstate central offices in the years after. Still, that does not
|
||
|
mean full service. Not for post-pay. You can't make a 1+ call for
|
||
|
instance. That's a limitation of the simple post-pay phone and the
|
||
|
equipment at the CO. Three kinds of trunks were set up for post-pay
|
||
|
calls. Which kind a CO uses depends on what kind of hardware was
|
||
|
purchased for the central office.
|
||
|
|
||
|
(a) Dedicated post-pay trunks. Self explanatory. These channels
|
||
|
are used only for post-pay calls. Might be necessary where the serving
|
||
|
central office does not pass automatic number identification or (ANI) to
|
||
|
the operator. This would be for very simple central offices. Most CO's
|
||
|
put their long distance traffic in digital form. The caller's number is
|
||
|
encoded as well. This data stream is decoded at the operator position.
|
||
|
They then know what number you are calling from. Not passing ANI
|
||
|
means a lack of equipment at the CO or that the trunk can't handle in. In
|
||
|
any case, all long distance calls from the post-pay phone go directly to
|
||
|
the operator. If the calls weren't intercepted then someone could clip
|
||
|
into the lines.
|
||
|
|
||
|
(b) Combined post-pay trunks. These handle regular traffic and
|
||
|
coin traffic. A more efficient use of the trunk. A dedicated channel isn't
|
||
|
left unused all the time, waiting for a call. The central office must have
|
||
|
ANI. This allows TSPS to automatically check a data base of all
|
||
|
American payphone numbers. The operator is then alerted that they are
|
||
|
dealing with a post-pay call by a lamp that is lit on the TSPS console.
|
||
|
The operator must handle the rest of the call. I am unsure of how they
|
||
|
do this. I do know that non-TSPS operators place a 1+ call. If the
|
||
|
connection is made then they tell you to deposit your money.
|
||
|
|
||
|
(c) Combined post-pay trunks with service tone identification.
|
||
|
Signals the operator with a tone. Alerts the operator to a post-pay call.
|
||
|
The central office generates this instead of passing ANI. It seems that
|
||
|
this would be less costly for the local office than providing the
|
||
|
equipment to encode ANI.
|
||
|
|
||
|
9. Not all remote areas can be economically served by the remote
|
||
|
trunking arrangement. Much of independent phone company traffic
|
||
|
goes to a non TSPS operator. Let me know if you know more. Or if
|
||
|
you know whether any of these trunking arrangements still remains.
|
||
|
There have been many changes now that most long distance traffic is on
|
||
|
fiber optic cable. Let's end this introduction to post pay by discussing
|
||
|
its signaling.
|
||
|
|
||
|
G. Post-pay signaling
|
||
|
|
||
|
10. Post-pay signaling is basic, reflecting the simplicity of the
|
||
|
community dial office equipment. There are two essential kinds of
|
||
|
signaling: answer supervision and coin deposit tones. Let's look at
|
||
|
supervision generally and then answer supervision in particular.
|
||
|
|
||
|
Supervision
|
||
|
|
||
|
11. Supervision is a mostly automatic activity of the phone system. It is
|
||
|
a process. Supervision is the way that phone equipment looks for and
|
||
|
responds to, phones going on hook and off hook. It's sometimes called
|
||
|
switch hook supervision. Supervision has also been described as "the
|
||
|
constant monitoring and controlling of the status of a call."(9)This
|
||
|
implies a great deal. Perhaps too much.(10) Since supervision is a
|
||
|
process rather than one simple signal it is a little more difficult to
|
||
|
understand. The language of signaling, in addition, makes this even
|
||
|
harder. You'll read such cryptic phrases as "supervision is passed
|
||
|
through the switching network" or "the call was suped." Let's look at
|
||
|
answer supervision in general.
|
||
|
|
||
|
Answer supervision
|
||
|
|
||
|
12. This happens when we answer the telephone. It is quite a process:
|
||
|
|
||
|
(a) Lifting the handset off the phone causes the switch hook buttons to
|
||
|
rise. This trips a relay inside the set that closes the contacts with the
|
||
|
phone line. This, in turn, connects the phone with the central office;
|
||
|
|
||
|
(b) Voltage now flows in the loop. The phone is now consuming power
|
||
|
like any electrical appliance. This flow is then detected by the switching
|
||
|
equipment;
|
||
|
|
||
|
(c) The central office now stops the ringing voltage. After all, you've
|
||
|
just answered the phone;
|
||
|
|
||
|
(d) The CO then cancels ringback for the calling party. This is the
|
||
|
"ringing" sound that you hear when you call a number. It's
|
||
|
produced and canceled by the CO;
|
||
|
|
||
|
(e) Switching equipment then sets up a connection between both parties
|
||
|
so that conversation can take place.
|
||
|
|
||
|
13. Answer supervision involves many things. The only real signal,
|
||
|
though, is the one made by the phone going off hook. The rest is
|
||
|
automatic. The chief requirement for the central office is to quickly
|
||
|
detect a request for service. This is the "constant monitoring" part of
|
||
|
supervision that we noted earlier. The other part, "the controlling of the
|
||
|
status of the call" should be obvious now; a number of things happen
|
||
|
when we pick up the phone. To repeat, by answering the phone the call
|
||
|
is supervised. Let's look at a variant.
|
||
|
|
||
|
Reverse battery answer supervision
|
||
|
|
||
|
15. Payphones use a type of answer supervision called reverse battery.
|
||
|
Post-pay depends on this almost exclusively. This signal is not peculiar
|
||
|
to coin phones but they do use it for special functions. Reverse battery
|
||
|
can prevent a call from taking place until a coin is deposited in the
|
||
|
payphone. The phone system changes the telephone line's electrical
|
||
|
status to do this. Sound confusing? The terminology is. But the actual
|
||
|
technique is simple, certainly well fitted to the CDO and a post-pay coin
|
||
|
line.
|
||
|
|
||
|
16. Reverse battery is a supervisory signal. It tells the payphone to
|
||
|
disable its transmitter and keypad until a coin is deposited. This prevents
|
||
|
a free call by not allowing any speech or any DTMF signal to be
|
||
|
transmitted until a coin is deposited. This prevents you, for instance,
|
||
|
from retrieving messages on your answering machine with the keypad
|
||
|
on a post pay coin phone. Reverse battery depends on receiving answer
|
||
|
supervision first. The end office detects that the called party has gone
|
||
|
off hook in the normal way. Instead of connecting the two parties,
|
||
|
however, a special relay is tripped at the switching office. This relay
|
||
|
changes the normal electrical condition of the line. Let's take this step by
|
||
|
step.
|
||
|
|
||
|
17. A post-pay coin line has the tip side wire grounded and the ring
|
||
|
side wire closed.(11) This is a little difficult to explain.(12) Both tip and
|
||
|
ring are closed when a normal phone is off hook. Closing the circuit
|
||
|
completes a connection with the central office. With post-pay, the tip is
|
||
|
grounded, usually to a chassis ground. That's just a screw or bolt inside
|
||
|
the payphone housing that a wire runs to. Tip is grounded or shorted
|
||
|
out when the handset is lifted. But the ring side wire is closed, allowing
|
||
|
a connection to the CO with one wire. You are able to dial your number
|
||
|
with this setup.
|
||
|
|
||
|
18. A connection is then made. Answer supervision is returned to the
|
||
|
central office by the called phone. It trips the special relay, the line
|
||
|
circuit relay, at the CO. This causes the tip and ring positions on the
|
||
|
coin phone line to be reversed. It closes the tip side and grounds the ring
|
||
|
side. This change of electrical status is the reverse battery signal. The
|
||
|
pay phone's coin relay senses this change. It's meant to. The relay is
|
||
|
polarity sensitive, engineered to short out the transmitter and keypad. In
|
||
|
other words, it works one way and not another. The line's status returns
|
||
|
to normal after a coin deposit. That's because a coin trips the rate relay .
|
||
|
That frees up the contacts and the line returns to normal.
|
||
|
|
||
|
19. Many electrical appliances won't work well or at all with the wrong
|
||
|
kind or quantity of electricity. Anything with transistors or integrated
|
||
|
circuits, such as a DTMF keypad, are especially vulnerable. Just
|
||
|
changing the voltage from a positive to a negative state is enough to
|
||
|
damage many things. This is fairly easy to understand. What is difficult
|
||
|
to understand, however, is that reverse battery does not mean reverse
|
||
|
voltage or reverse electrical polarity.
|
||
|
|
||
|
20. Freeman(13) and Reeve(14) state that a reverse battery signal uses
|
||
|
negative voltage and not positive. Yet Fike writes about "reversing the
|
||
|
polarity of the tip-ring pair."(15) Reeve further states that in post-pay
|
||
|
signaling "the line circuit reverses the battery polarity applied to the
|
||
|
loop."(16) How can this be? How can one talk about reversing polarity
|
||
|
when all the information shows that there is no change?
|
||
|
|
||
|
21. We usually think of polarity as a positive or negative state. In this
|
||
|
context, however, reverse polarity means that tip and ring have become
|
||
|
reversed, not voltage. Polarity is used in its broadest sense: the
|
||
|
condition of being polar or opposite. Tip and ring positions become
|
||
|
opposed in reverse battery, therefore, reverse polarity refers to a change
|
||
|
in position and not voltage. Reeve confirms this in his last footnote to
|
||
|
the chapter on coin line services. He explains that the keypad inhibit
|
||
|
signal should not be "confused with reverse battery, which is the
|
||
|
reversal of the battery and ground potentials on the tip and ring
|
||
|
leads."(17)
|
||
|
|
||
|
22. So, answer supervision causes reverse battery which prevents a call
|
||
|
until a coin is deposited. Depositing that coin resets the relay which puts
|
||
|
the line back to normal polarity. The only other important group of
|
||
|
signals for post-pay are coin deposit tones.
|
||
|
|
||
|
Coin Deposit Tones
|
||
|
|
||
|
23. A coin deposit tone is a signal that alerts an operator or a piece of
|
||
|
equipment that a certain coin has been put in. There are no specific post-
|
||
|
pay coin deposit tones. Since post pay is not compatible with automated
|
||
|
coin toll service, it could be assumed that dual tone frequency signaling
|
||
|
may not be necessary. But some post-pay phones are tied to TSPS
|
||
|
operators. Coin deposits total on their consoles while they watch and
|
||
|
listen to the tones. The central office probably sends the amount to
|
||
|
TSPS on a data circuit or a channel that connects the two. So, some
|
||
|
post-pay coin lines may demand the current models of telco payphones.
|
||
|
In addition, the newest phones, such as the D model, are far more
|
||
|
reliable than their predecessors. It might be risky to box to the operator
|
||
|
if you don't know which model you're dealing with. Bell System
|
||
|
practice was to systematically upgrade their coin phones over time. I
|
||
|
doubt that any older phones are left in service. Let's quickly look at
|
||
|
some payphone history, to give you an idea of the what might be
|
||
|
possible.
|
||
|
|
||
|
24. Western Electric came out with the 1A1 in 1965,(18) the product of
|
||
|
six years of research. It used a single frequency oscillator to produce a
|
||
|
2200 Hz tone for each coin. A nickel produced a single tone, a dime
|
||
|
two, and a quarter five. In 1968, the "C" type set was introduced. It had
|
||
|
a DTMF pad instead of a rotary dial. The single frequency oscillator
|
||
|
remained. It wasn't until 1979 that Bell Labs introduced a retrofit kit for
|
||
|
the A & C models.(19) This changed them from single frequency to
|
||
|
dual frequency They were now compatible with ACTS. The totalizer, or
|
||
|
coin counter, was changed from an electromechanical device to one
|
||
|
without any moving parts. This was done by using a piezoelectric
|
||
|
transducer, an electronic pad that each coin fell on when it was
|
||
|
deposited. There are three pads, one for each kind of coin. A nickel,
|
||
|
dime or quarter produces a certain amount of current when it falls on its
|
||
|
specific transducer. This current then triggers the oscillator to produce
|
||
|
a tone of 1700 Hz and 2200 Hz. I understand that the current model, the
|
||
|
"D" , is not a retrofit but simply a new phone with the new technology.
|
||
|
And then there was the Western Electric E.C.P.T., but that's another
|
||
|
story.
|
||
|
|
||
|
25. Automatic Electric should use similar coin signaling schemes in
|
||
|
order to be compatible with the rest of the telephone system. But even
|
||
|
the oldest of schemes can be used if the phone company operator places
|
||
|
your call. Three slot coin phones date from the 1920's, although they
|
||
|
were manufactured well into the 1960's. Some of these still exist,
|
||
|
although probably none in the former Bell System territory.(20) Most
|
||
|
three slot phones were modeled after a phone called the Gray pay
|
||
|
station.(21) These were produced by an independent company that
|
||
|
Western Electric later worked with. There were three coin chutes. They
|
||
|
could allow two tones at once if coins were put in at the same time, an
|
||
|
irritation to the operator. A nickel would strike a bronze gong,
|
||
|
confusingly called a bell. The tone was around 1100 Hz. A dime hit this
|
||
|
gong twice. A quarter would hit a helical flat wire, even more
|
||
|
confusingly called a cathedral gong and produce a lower tone of around
|
||
|
800 Hz. These tones were distinct enough for an operator to recognize.
|
||
|
They were not recognizable, however, to most automatic switching
|
||
|
equipment; ACTS, for example, never planned to incorporate the tones
|
||
|
of three slots.
|
||
|
|
||
|
|
||
|
(1) Fagen, M.D., ed. "A History of Engineering and Science in the Bell
|
||
|
System: The Early Years, 1875 -- 1925." New York: Bell Telephone
|
||
|
Laboratories, 1975. 156
|
||
|
|
||
|
(2) Fagen, 155
|
||
|
|
||
|
(3) Dial tone first operation began its reintroduction to the Bell System
|
||
|
in 1966. The reason? Public safety. The tests were in Hartford,
|
||
|
Massachusetts, the site of the first coin telephone. See A.E. Ruppel and
|
||
|
G. Spiro. 'No Dime Needed' Bell Laboratories Record (October, 1969)
|
||
|
296
|
||
|
|
||
|
(4) Rey, R.F., ed. "Engineering and Operations in the Bell System". 2d
|
||
|
ed. Murray Hills, N.J. AT&T Bell Laboratories. 1983. 473
|
||
|
|
||
|
(5) Rey, 461
|
||
|
|
||
|
(6) Schindler, 32
|
||
|
|
||
|
(7) Although the Bell System provided, perhaps, 75% of America's
|
||
|
population with service, they never covered more than half of the
|
||
|
geographical area of the country. This left a huge amount of the United
|
||
|
States, especially the West, with a welter of different operating systems.
|
||
|
Automatic Electric, the manufacturing arm of General Telephone and
|
||
|
Electronics, produced some fascinating and somewhat quirky equipment
|
||
|
over the years, both for wholly owned companies such as GTE of
|
||
|
California and for hundreds of independent telephone companies. Las
|
||
|
Vegas, Santa Barbara, Palm Springs and the Delta country of California
|
||
|
are good areas to investigate as well as much of the rural west. Some
|
||
|
eastern states still have party lines and rudimentary service as well. Feel
|
||
|
free to write to me about your favorite independent provider.
|
||
|
|
||
|
(8) S.M Bauman, R.S. DiPietro, and R.J. Jaeger Jr. "Remote Trunk
|
||
|
Arrangement: Overall Description and Operational Characteristics" Bell
|
||
|
System Technical Journal. 58.6 (July--August 1979) 1119
|
||
|
|
||
|
(9) Rey, 816
|
||
|
|
||
|
(10) Some maintain that addressing, or dialing, is part of supervision.
|
||
|
By dialing a number you control the status of a call. True enough.
|
||
|
Operators do too, however, by asking you to put in more money or to
|
||
|
dial a number again. ACTS controls a great deal of coin calls. Are these
|
||
|
supervisory signals?
|
||
|
|
||
|
(11) Reeve, Whitman D. "Subscriber Loop Signaling and Transmission
|
||
|
Handbook: Analog." New York: Institute of Electrical and Electronics
|
||
|
Engineers. IEEE Press. 1992. 217 A great book. The best, most current
|
||
|
explanation of the local loop. Excellent chapter named Coin Line
|
||
|
Services. Find this book. It's usually checked out. Do an inter-libary
|
||
|
loan if you have to.
|
||
|
|
||
|
(12) Nothing is more frustrating to explain than the various
|
||
|
combinations of tip, ring and ground. But nothing is more important to
|
||
|
understanding coin phone signaling. I put some illustrations in the
|
||
|
second issue that explain this better.
|
||
|
|
||
|
(13) Freeman, Roger. L. "Reference Manual for Telecommunications
|
||
|
Engineering." Wiley Interscience. New York. 1985. 81 Well worth
|
||
|
browsing though. Look for it in the reserve section. Freeman is a well
|
||
|
respected authority.
|
||
|
|
||
|
(14) Reeve, 217
|
||
|
|
||
|
(15) Fike, 193
|
||
|
|
||
|
(16) Reeve, 217
|
||
|
|
||
|
(17) Reeve, 223
|
||
|
|
||
|
(18) Stokes, R.R., 'A Single-Slot Coin Telephone' Bell Laboratories
|
||
|
Record (January, 1966) 20 Details the 1A1, the payphone that became a
|
||
|
standard.
|
||
|
|
||
|
(19) Habib 'Coin Handling Goes Electronic' Bell Laboratories Record
|
||
|
(April, 1979) 95
|
||
|
|
||
|
(20) I used a three slot last year in Jordan Valley, Oregon. It was a beat
|
||
|
up Automatic Electric, with half its armor missing. My 1+ call to Boise
|
||
|
was intercepted by an operator with the, I believe, Telephone Utilities of
|
||
|
Eastern Oregon. It was great, I felt like I was in Mayberry, trying to
|
||
|
place a call to Mount Pilot.
|
||
|
|
||
|
(21) Fagen. M.D. ed., "A History of Engineering and Science in the
|
||
|
Bell System: The Early Years (1875--1925)" 159 The picture of the
|
||
|
three slot phone is nearly identical to the ones that W.E. produced nearly
|
||
|
fifty years later. A.E. types are a little bulkier and rounded on the edges.
|
||
|
And, yes, you should look at Fagen's book, too. It's curiously
|
||
|
subtitled, this 1000 page monster actually covers many things past the
|
||
|
1950's.
|
||
|
|
||
|
More next issue . . . (August)
|
||
|
|
||
|
------------------------------------------------------
|
||
|
|
||
|
7. A CONVERSATION WITH MOTOROLA
|
||
|
|
||
|
In the hardcopy edition I reprinted a Motorola ad from earlier in the
|
||
|
year. The illustration depicts a group of grimly faced emergency
|
||
|
services people. Firefighters, EMTs, doctors and police stare out from
|
||
|
the gloomy looking page. The artwork seems to be done in pencil and
|
||
|
charcoal. I reprint the text of the ad first in quotation marks. My
|
||
|
comments follow.
|
||
|
|
||
|
"ATTENTION: PUBLIC SAFETY ANNOUNCEMENT
|
||
|
|
||
|
Tampering With Motorola's Communication Technology Is Nothing
|
||
|
Short of a Crime
|
||
|
|
||
|
Motorola has been at the forefront of communications technology for
|
||
|
more than 60 years. Today, we offer a greater array of communications
|
||
|
products than ever before. We are proud of our products and the vital
|
||
|
services that they bring to our customers which are of unparalleled
|
||
|
public importance.
|
||
|
|
||
|
Theft of communication services and so-called High-Tech piracy
|
||
|
threaten the entire communication industry's reputation for reliability.
|
||
|
This conduct not only damages the reputation of Motorola, Inc. and the
|
||
|
communication industry, but undermines the very integrity of America's
|
||
|
public and private communications services.
|
||
|
|
||
|
Motorola intends to combat this conduct by aggressively maintaining
|
||
|
and enforcing its rights to its hardware and software technology.
|
||
|
Anyone who has knowledge of illegal activities or has questions
|
||
|
concerning such activities is urged to contact Motorola Inc. immediately
|
||
|
at 1-800-325-4036. Contacts will be kept confidential and may be made
|
||
|
anonymously.
|
||
|
|
||
|
Motorola"
|
||
|
|
||
|
This curious ad has been placed for many months in the three
|
||
|
largest ham radio magazines: CQ, QST and 73 Amateur Radio Today.
|
||
|
I thought at first that Motorola was talking about cell fraud. But how can
|
||
|
a pirated call affect "the very integrity of America's "public and private
|
||
|
communication services"? And why are they advertising in amateur
|
||
|
radio magazines? Are the real hackers in radio? What's going on? The
|
||
|
ad said to call with questions. So I did.
|
||
|
|
||
|
I talked to a Mr. John England. He said the ad had nothing to
|
||
|
do with cell fraud. Instead, it had to do with pirating commercial radio
|
||
|
services, you know, car to car, car to dispatcher, that sort of thing.
|
||
|
England said that they knew about amateurs who, for a price, would set
|
||
|
up a commercial radio and its software to work on emergency services
|
||
|
frequencies. He said that Motorola is working with "all the appropriate
|
||
|
federal agencies" in their investigations. He admitted, however, that no
|
||
|
one had ever been convicted of doing what the ad was concerned with.
|
||
|
He mentioned, somewhat sheepishly, that there were other ways to stop
|
||
|
an activity without imposing a criminal penalty. Like having someone
|
||
|
pay a fine. Oh, really?
|
||
|
|
||
|
Hackers are rotting in jail for nothing more than a low-rent
|
||
|
economic crime or because they supposedly invaded, according to the
|
||
|
most crippled definition possible, someone's electronic privacy. And yet
|
||
|
Motorola and the Feds will negotiate with people who deliberately
|
||
|
interfere with emergency services? Someone who gets in the way of
|
||
|
fire, police or ambulance service should go to jail. But I know of no one
|
||
|
in the hacker community who has ever sought to do such a thing.
|
||
|
|
||
|
Radio amateurs take great pride in a good public image. They do
|
||
|
a great deal of self-policing. Some amateurs have done stupid, criminal
|
||
|
things, like making false distress calls. But rarely do they go to jail.
|
||
|
Licenses are pulled and fines imposed. I suppose that Motorola could be
|
||
|
trying to scare people off. England said that the "bad news bears know
|
||
|
exactly who they are." A proactive approach is always good, generally.
|
||
|
I think though, that you won't see a warning from Motorola about
|
||
|
experimenting with cellular phones. If there's trouble it seems more
|
||
|
likely that the Secret Service will be involved, that you will be arrested
|
||
|
and that you will go to jail. I doubt that much negotiating will go on,
|
||
|
even if you were just calling a mailbox. Sounds like you're safer
|
||
|
playing with the police. Go figure.
|
||
|
|
||
|
-----------------------------------------
|
||
|
|
||
|
7. THE GTE RTSS PHONE
|
||
|
|
||
|
In this article I reproduced an ad for a General Telephone and
|
||
|
Electronics Red Telephone Switching System phone. I asked for help in
|
||
|
identifying some of the strange acronyms and abbreviations. I ask for
|
||
|
comments from the readers of the electronic version as well. The ad is a
|
||
|
photograph of the phone with text. Yes, the phone is a nice red color.
|
||
|
My magazine is, unfortunately, in black and white. Still, you may find
|
||
|
the ad in 'Air Force' magazine and some other mainstream publications.
|
||
|
It looks similar to a generic ISDN phone but with the Autovon keys and
|
||
|
with some sort of LCD display. The display looks to be about 2" by 4".
|
||
|
Here's the text:
|
||
|
|
||
|
Look where you can go with One GTE RTSS phone
|
||
|
|
||
|
ANDVT
|
||
|
AUTOVON
|
||
|
CLASS A DIALLINE
|
||
|
DEFENSE SWITCHED NETWORK
|
||
|
JCSCAN
|
||
|
KG-81/94, TRUNKS & MULTIPLE REMOTE SUBSCRIBER UNIT
|
||
|
KY-3 AUTOSEVOCOM
|
||
|
LAND MOBILE RADIO
|
||
|
LONG-HAUL HOTLINES
|
||
|
ON-BASE HOTLINES
|
||
|
RED SWITCH NETWORK
|
||
|
SATCOM RADIO
|
||
|
STU-II KY-71/ PARKHILL KY-65/75
|
||
|
STU III
|
||
|
TACTICAL GATEWAY DSVT KY-68
|
||
|
TACTICAL SWITCH DROP
|
||
|
UHF RADIO
|
||
|
VHF RADIO
|
||
|
|
||
|
With GTE's Red Telephone Switching System (RTSS), a single
|
||
|
phone gives you total Red/Black voice communications access to all
|
||
|
these places . . . with unequalled security. It also provides robust
|
||
|
connectivity and interoperability with other existing and future secure
|
||
|
voice systems - - tactical, strategic, and commercial. A 20-year life-cycle
|
||
|
support program is backed by a proven GTE worldwide field support
|
||
|
and logistics system. You, too, can order RTSS under Contract No.
|
||
|
F34608-88-D0007 from the DoD through HQ EID, Tinker AFB,
|
||
|
Oklahoma.
|
||
|
|
||
|
If you use more than one phone for secure/non-secure
|
||
|
communications, you haven't been authorized RTSS. -----------------
|
||
|
GTE Government Systems"
|
||
|
|
||
|
This ad details an exciting looking phone. I know nothing about it. Let
|
||
|
me know if you can help by filling in the details. I'll get the guessing
|
||
|
game going. Much has been written about Autovon. It utilizes the four
|
||
|
right hand buttons: flash overide, flash, intercept and priority. These
|
||
|
correspond to the four extra tones that are built into most DTMF IC's.
|
||
|
These silver box tones are not often used by most telcos but they are
|
||
|
used by Autovon to prioritize phone calls when they are first placed.
|
||
|
|
||
|
Anyway, the Red Switch Network would have to piggyback onto
|
||
|
Autovon if it is being included in this phone. Wouldn't it? And what are
|
||
|
Red/Black voice communications? One of the colors probably stands for
|
||
|
secure voice communications. And I mean secure. It's likely that an
|
||
|
imbedded chip in the phone does the NSA certified encryption. So, you
|
||
|
have a secure line immediately with no need to interface with anything
|
||
|
else. As such, it is probably classified as a "controlled cryptographic
|
||
|
item." It probably allows only one person to speak at a time when it's in
|
||
|
the secure mode.
|
||
|
|
||
|
KY-3 AUTOSEVOCOM should stand for automatically secure voice
|
||
|
communications. Comsec stands for the obvious: secure
|
||
|
communication. There are, apparently, many forms of comsec. Some of
|
||
|
them are KY-57, ANDVT, and KG-84. The field radio receiving this
|
||
|
traffic is called, I think, a processor. Motorola makes a unit called the
|
||
|
Sunburst II processor.
|
||
|
|
||
|
---------------------
|
||
|
|
||
|
8. CALIFORNIA TOLL FRAUD LAW
|
||
|
|
||
|
Many laws relate to telephones. Here's the text of one along with my
|
||
|
comments. (This is far less confusing in the hard copy edition since I
|
||
|
am able to italicize my comments.) Broad ranging code sections give the
|
||
|
police the power to move against nearly any one at any time. In reality,
|
||
|
the law is mostly used against high profile criminals, gangs of
|
||
|
criminals, people who get caught red handed and people who can't
|
||
|
afford to challenge bad law.
|
||
|
|
||
|
California Penal Code Section 502.7 Obtaining telephone or telegraph
|
||
|
service by fraud
|
||
|
|
||
|
"(a) Any person who knowingly, willfully, and with intent to defraud a
|
||
|
person providing telephone or telegraph service, avoids or attempts to
|
||
|
avoid, or aids, abets or causes another to avoid the lawful charge, in
|
||
|
whole or in part, for telephone or telegraph service by any of the
|
||
|
following means is guilty of a misdemeanor or a felony, except as
|
||
|
provided in subdivision (g): . . ."
|
||
|
|
||
|
(The main clause. Rather generic on purpose. You may be charged with
|
||
|
this at first if you are arrested for something telephonic. The initial
|
||
|
charge is the booking charge. The DA decides the specific charges later,
|
||
|
often making it more detailed with the help of the rest of this code
|
||
|
section.)
|
||
|
|
||
|
"(1) By charging the service to an existing telephone number or
|
||
|
credit card number without the authority of the subscriber thereto or the
|
||
|
lawful holder thereof. . . ."
|
||
|
|
||
|
(Prohibits telephone theft by wrongful billing or credit card fraud.)
|
||
|
|
||
|
"(2) By charging the service to a non-existent telephone number
|
||
|
or credit card number, or to a number that associated with telephone
|
||
|
service which is suspended or terminated, or to a revoked or canceled
|
||
|
(as distinguished from expired) credit card number, notice of the
|
||
|
suspension, termination, revocation, or cancellation of the telephone
|
||
|
service or credit card having been given to the subscriber thereto or the
|
||
|
holder thereof. . ."
|
||
|
|
||
|
(Legitimate card holders can't be jailed for mistakenly using an expired
|
||
|
card. Or, at least, they're not supposed to be. There's not much risk of
|
||
|
this provision being abused since most cards are canceled automatically
|
||
|
upon expiration.)
|
||
|
|
||
|
"(3) By use of a code, prearranged scheme, or other similar
|
||
|
stratagem or device whereby the person, in effect, sends or receives
|
||
|
information. . ."
|
||
|
|
||
|
(I am not sure what this refers to. Can anyone give me an example of
|
||
|
what the legislature meant by this?)
|
||
|
|
||
|
"(4) By rearranging, tampering with, or making connection with
|
||
|
telephone or telegraph facilities or equipment, whether physically,
|
||
|
electrically, acoustically, inductively, or otherwise, or by using
|
||
|
telephone or telegraph service with knowledge or reason to believe that
|
||
|
the rearrangement, tampering, or connection existed at the time."
|
||
|
|
||
|
(Prohibits fraud by technical means. What's so unfortunate is that credit
|
||
|
card thieves are put into the same section as hackers. This might explain
|
||
|
some law enforcement paranoia, since the two groups of people fall
|
||
|
under the same section. Tone generators would probably be prohibited
|
||
|
by this subsection.)
|
||
|
|
||
|
"(5) By using any other deception, false pretense, trick, scheme,
|
||
|
device, conspiracy, or means, including the fraudulent use of altered or
|
||
|
stolen information."
|
||
|
|
||
|
(Legitimate means to us are probably tricks and schemes to the
|
||
|
uninformed. Does an Internet dialout mean anything to an assistant
|
||
|
district attorney who intends, someday, to log onto Prodigy?)
|
||
|
|
||
|
"(b) Any person who does either of the following is guilty of a
|
||
|
misdemeanor or a felony, except as provided in subdivision (g):
|
||
|
|
||
|
"(1) Makes, possesses, sells, gives, or otherwise transfers to
|
||
|
another, or offers or advertises any instrument, apparatus, or device
|
||
|
with intent to use it with knowledge or reason to believe it is intended to
|
||
|
be used to avoid any lawful telephone or telegraph charge or to conceal
|
||
|
the existence or place of origin or destination of any telephone or
|
||
|
telegraph message. . ."
|
||
|
|
||
|
(The first part of this paragraph prohibits the selling or distributing of
|
||
|
an assembled toll fraud device. The second part is a little cryptic. It
|
||
|
refers to a device that can mask a caller's location. Sounds like a call
|
||
|
forwarding device. I'll have to look into the committee reports to see
|
||
|
what tool so spooked the legislature that they made it illegal.)
|
||
|
|
||
|
"(2) Sells, gives, or otherwise transfers to another, or offers or
|
||
|
advertises plans or instructions for making or assembling an instrument,
|
||
|
apparatus, or device described in paragraph (1) of this subdivision with
|
||
|
knowledge or reason to believe that they may be used to make or
|
||
|
assemble the device."
|
||
|
|
||
|
(Prohibits distributing plans for a toll fraud device. You can't even give
|
||
|
them away. But it's selective. An issue of Harper's was pulled off
|
||
|
shelves in the early 1970's for an article on blue boxing. And yet 2600
|
||
|
did not get their summer 1993 edition pulled in California because of the
|
||
|
red box schematic. Tap was shut down, I believe, for printing articles
|
||
|
on toll fraud devices. And yes, you can buy books on how to make C-
|
||
|
4, modify an AR-15 to fire on full auto, or learn how to cut the brake
|
||
|
lines on a bus. Just look in the back of Soldier of Fortune or order a
|
||
|
catalog from Paladin Press. In fact, I could publish a magazine called
|
||
|
KILL!, containing articles on how to beat, torture and maim people in
|
||
|
dozens of ways. And it would be legal. So long as I didn't put in a red
|
||
|
box schematic. Do you think any telco executive would worry about my
|
||
|
new zine? Of course not, in fact, they'd probably try to sell me an 800
|
||
|
number for my new business. The concern of the legislature and the
|
||
|
telco is about profits and the control of technology. Don't believe
|
||
|
anything else.)
|
||
|
|
||
|
"(c) Any person who publishes the number or code of an existing,
|
||
|
canceled, revoked expired, or nonexistent (!) credit card, or the
|
||
|
numbering or coding which is employed in the issuing of credit cards
|
||
|
with the intent that it be used or with the knowledge or the reason that it
|
||
|
will be used to avoid the payment of any lawful telephone or telegraph
|
||
|
bill is guilty of a misdemeanor. Subdivision (g) shall not apply to this
|
||
|
subdivision. As used in this section publishes means the communication
|
||
|
of information to any one or more persons, either orally, in person or by
|
||
|
telephone, radio, or television, or electronic means, including, but not
|
||
|
limited to, a bulletin board system, or in a writing of any kind, including
|
||
|
without limitation, a letter or memorandum, circular or handbill,
|
||
|
newspaper, or magazine article, or book."
|
||
|
|
||
|
(Okay, we get it. It's illegal to talk about calling card numbers if you
|
||
|
intend to defraud a telephone company. It's even illegal to talk about
|
||
|
something that doesn't exist. But what if you are talking and writing
|
||
|
about numbering schemes because you are simply interested? Intent
|
||
|
must be proved by act. There has to be some overt evidence that you
|
||
|
intend to defraud. Usually. Nowadays, I think that mere possession of
|
||
|
such material will get you in trouble.)
|
||
|
|
||
|
"(d) Any person who is the issuee of a calling card, credit card, calling
|
||
|
code, or any other means or device for the legal use of
|
||
|
telecommunications services and who receives anything of value for
|
||
|
knowingly allowing another person to use the means or device in order
|
||
|
to fraudulently obtain telecommunications services is guilty of a
|
||
|
misdemeanor or a felony, except as provided in subdivision (g)."
|
||
|
|
||
|
(This makes it illegal for telco people to let someone else use their
|
||
|
equipment, codes or credit cards.)
|
||
|
|
||
|
"(e) Subdivision (a) applies when the telephone or telegraph
|
||
|
communication involved either originates or terminates, in this state, or
|
||
|
when the charges for services would have been billable, in normal
|
||
|
course, by a person providing telephone or telegraph service in this
|
||
|
state, but for the fact that the charge was avoided, or attempted to be
|
||
|
avoided, by one or more of the means set forth in subdivision (a)."
|
||
|
|
||
|
"(g) Theft of any telephone or telegraph services under this section by a
|
||
|
person who has a prior misdemeanor or felony conviction for theft of
|
||
|
services under this section within the past five years, is a felony."
|
||
|
|
||
|
(A felony if you have a prior under this law. You go to state prison for
|
||
|
at least a year. Misdemeanors can't be punished by more than a year in a
|
||
|
county jail.)
|
||
|
|
||
|
"(h) Any person or telephone company defrauded by any acts prohibited
|
||
|
under this section shall be entitled to restitution for the entire amount of
|
||
|
the charges avoided from any person or persons convicted under this
|
||
|
section."
|
||
|
|
||
|
"(i) Any instrument, apparatus, device, plans, instructions, or written
|
||
|
publication described in subdivision (b) or (c) may be seized under
|
||
|
warrant or incident to a lawful arrest, and, upon the conviction of a
|
||
|
person for violation of subdivision (a), (b), or (c), the instrument,
|
||
|
apparatus, device, plans, instructions, or written publication may be
|
||
|
destroyed as contraband by the sheriff of the county in which the person
|
||
|
was convicted or turned over to the person providing telephone or
|
||
|
telegraph service in the territory in which it was seized."
|
||
|
|
||
|
(The police can seize anything that might be used in a prosecution. They
|
||
|
can do it with a warrant or they can grab it if they take you in for, say,
|
||
|
loitering. You have no hope that the police will return contraband.
|
||
|
None. Material that may or may not be contraband will probably be
|
||
|
kept as the investigation moves forward. There is little hope that
|
||
|
anything suspicious will be returned until after trial. It's possible
|
||
|
evidence, after all. You could be waiting for many, many months or
|
||
|
more.)
|
||
|
|
||
|
"(j) Any computer, computer system, computer network, or any
|
||
|
software or data, owned by the defendant, which is used during the
|
||
|
commission of any public offense described in this section or any
|
||
|
computer, owned by the defendant, which is used as a repository for the
|
||
|
storage of software or data illegally obtained in violation of this section
|
||
|
shall be subject to forfeiture."
|
||
|
|
||
|
(Hope you can loose your computer while the Powers That Be decide
|
||
|
your fate. With the proper warrant they can confiscate everything. You
|
||
|
then chew your fingernails for months while they search your files and
|
||
|
decide on strategy. Maybe they'll move forward with your case. Maybe
|
||
|
not. Securely encrypting your most sensitive files would seem wise. A
|
||
|
case would have to be built on other things. But if they do issue a
|
||
|
warrant then you have probably been watched for some time. So, they
|
||
|
may have other evidence. And they'll be mad as hell about not breaking
|
||
|
a particular file. They may become more determined. It's up to you and
|
||
|
your lawyer to figure out how to proceed.
|
||
|
|
||
|
Some hackers are thieves but not all thieves are hackers. I understand
|
||
|
that the legislature wanted to have one code section just for toll fraud.
|
||
|
But experimenting with the phone system is a far different thing than
|
||
|
seeking to exploit it. Anyone who thinks that a red box tone can hurt the
|
||
|
security of the network or cause damage to a switch is a fool or a
|
||
|
corporate liar. In the next issue I'll reprint Penal Code Section 502.8,
|
||
|
the law prohibiting cellular phone fraud.)
|
||
|
--------------------------------------
|
||
|
|
||
|
9. PRIVATE LINE INFORMATION
|
||
|
|
||
|
The Rates
|
||
|
|
||
|
A full page ad costs $75.00. A half page costs $37.50. A quarter page
|
||
|
costs $18.75. This applies to the first newsstand edition which will
|
||
|
come out in January, 1995. There is no requirement to be a subscriber
|
||
|
in order to advertise. You can reserve this rate for all of 1995 by placing
|
||
|
an ad in January's edition. You don't need to pay in advance to reserve;
|
||
|
just tell me that you intend to do it. Payment and camera ready art work
|
||
|
for the first month's advertisements are due one month before each issue
|
||
|
comes out. A photocopy of the page that the ad is on will be sent out
|
||
|
once a particular issue is completed. Classified ads of 25 words or less
|
||
|
are free to subscribers. Comments? Corrections?
|
||
|
e-mail Tom Farley -- privateline@delphi.com THANK YOU!
|
||
|
|
||
|
|
||
|
|
||
|
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