******BIOC Agent 003's course in*******
                     *                                     *
                     *     ==========================      *
                     *     =BASIC TELECOMMUNICATIONS=      *
                     *     ==========================      *
                     *               Part VI               *
                     ***************************************
REVISED:  27-OCT-84
Preface:
This article will focus primarily on the standard Western Electric single- slot
coin telephone (aka fortress fone) which can be divided into 3 types:
- Dial-Tone First (DTF)
- Coin-First (CF):  (ie, it wants your $ before you receive a dial tone)
- Dial Post-Pay Service (PP):  you pay after the party answers
Depositing Coins (Slugs):
-------------------------
Once you have deposited your slug into a fortress, it is subjected to a gamut
of tests.
The first obstacal for a slug is the magnetic trap.  This will stop any
light-weight magnetic slugs and coins.  If it passes this, the slug is then
classified as a nickel, dime, or quarter.  Each slug is then checked for
appropriate size and weight.  If these tests are passed, it will then travel
through a nickel, dime, or quarter magnet as appropriate.  These magnets set up
an eddy current effect which causes coins of the appropriate characteristics to
slow down so they will follow the correct trajectory.  If all goes well, the
coin will follow the correct path (such as bouncing off of the nickel anvil)
where it will hopefully fall into the narrow accepted coin channel.
The rather elaborate tests that are performed as the coin travels down the coin
chute will stop most slugs and other undesirable coins, such as pennies, which
must then be retrieved using the coin release lever.
If the slug miraculously survives the gamut, it will then strike the
appropriate totalizer arm causing a ratchet wheel to rotate once for every
5-cent increment (eg, a quarter will cause it to rotate 5 times).
The totalizer then causes the coin signal oscillator to readout a dual-
frequency signal indicating the value deposited to ACTS (a computer) or the
TSPS operator.  These are the same tones used by phreaks in the infamous red
boxes.
For a quarter, 5 beep tones are outpulsed at 12-17 pulses per second (PPS).  A
dime causes 2 beep tones at 5 - 8.5 PPS while a nickel causes one beep tone at
5 - 8.5 PPS.  A beep consists of 2 tones:  2200 + 1700 Hz.
A relay in the fortress called the "B relay" (yes, there is also an 'A relay')
places a capacitor across the speech circuit during totalizer read- out to
prevent the "customer" from hearing the red box tones.
In older 3 slot phones:  one bell (1050-1100 Hz) for a nickel, two bells for a
dime, and one gong (800 Hz) for a quarter are used instead of the modern
dual-frequency tones.
=============
=TSPS & ACTS=
=============
While fortresses are connected to the CO of the area, all transactions are
handled via the Traffic Service Position System (TSPS).  In areas that do not
have ACTS, all calls that require operator assistance, such as calling card and
collect, are automatically routed to a TSPS operator position.
In an effort to automate fortress service, a computer system known as Automated
Coin Toll Service (ACTS) has been implemented in many areas.  ACTS listens to
the red box signals from the fones and takes appropriate action.  It is ACTS
which says, "Two dollars please (pause) Please deposit two dollars for the next
ten seconds" (and other variations).  Also, if you talk for more than three
minutes and then hang-up, ACTS will call back and demand your money.  ACTS is
also responsible for Automated Calling Card Service.
ACTS also provide trouble diagnosis for craftspeople (repairmen specializing in
fortresses).  For example, there is a coin test which is great for tuning up
red boxes.  In many areas this test can be activated by dialing 09591230 at a
fortress (thanks to Karl Marx for this information).  Once activated it will
request that you deposit various coins.  It will then identify the coin and
outpulse the appropriate red box signal.  The coins are usually returned when
you hang up.
To make sure that there is actually money in the fone, the CO initiates a
"ground test" at various times to determine if a coin is actually in the fone.
This is why you must deposit at least a nickel in order to use a red box!
Green Boxes:
------------
Paying the initial rate in order to use a red box (on certain fortresses) left
a sour taste in many red boxer's mouths thus the GREEN BOX was invented.  The
green box generates useful tones such as COIN COLLECT, COIN RETURN, and
RINGBACK.  These are the tones that ACTS or the TSPS operator would send to the
CO when appropriate.  Unfortunately, the green box cannot be used at a fortress
station but it must be used by the CALLED party.
Here are the tones:
     COIN COLLECT       700 + 1100 Hz
     COIN RETURN       1100 + 1700 Hz
     RINGBACK           700 + 1700 Hz
Before the called party sends any of these tones, an operator released signal
should be sent to alert the MF detectors at the CO.  This can be accomplished
by sending 900 + 1500 Hz or a single 2600 Hz wink (90 ms) followed by a 60 ms
gap and then the appropriate signal for at least 900 ms.
Also, do not forget that the initial rate is collected shortly before the 3
minute period is up.
Incidentally, once the above MF tones for collecting and returning coins reach
the CO, they are converted into an appropriate DC pulse (-130 volts for return
& +130 volts for collect).  This pulse is then sent down the tip to the
fortress.  This causes the coin relay to either return or collect the coins.
The alleged "T-Network" takes advantage of this information.  When a pulse for
COIN COLLECT (+130 VDC) is sent down the line, it must be grounded somewhere.
This is usually either the yellow or black wire.  Thus, if the wires are
exposed, these wires can be cut to prevent the pulse from being grounded.  When
the three minute initial period is almost up, make sure that the black & yellow
wires are severed; then hang up, wait about 15 seconds in case of a second
pulse, reconnect the wires, pick up the fone, hang up again, and if all goes
well it should be "JACKPOT" time.
Physical Attack:
----------------
A typical fortress weighs roughly 50 lbs.  with an empty coin box.  Most of
this is accounted for in the armor plating.  Why all the security?  Well, Bell
contributes it to the following:
"Social changes during the 1960's made the multislot coin station a prime
target for:  vandalism, strong arm robbery, fraud, and theft of service.  This
brought about the introduction of the more rugged single slot coin station and
a new environment for coin service."
As for picking the lock, I will quote Mr.  Phelps:  "We often fantasize about
'picking the lock' or 'getting a master key.' Well, you can forget about it.  I
don't like to discourage people, but it will save you from wasting alot of your
time--time which can be put to better use (heh, heh)."
As for physical attack, the coin plate is secured on all four side by hardened
steel bolts which pass through two slots each.  These bolts are in turn
interlocked by the main lock.
One phreak I know did manage to take one of the 'mothers' home (which was
attached to a piece of plywood at a construction site; otherwise, the permanent
ones are a bitch to detach from the wall!).  It took him almost ten hours to
open the coin box using a power drill, sledge hammers, and crow bars (which was
empty -- perhaps next time, he will deposit a coin first to hear if it slushes
down nicely or hits the empty bottom with a clunk.)
Taking the fone offers a higher margin of success.  Although this may be
difficult often requiring brute force and there has been several cases of back
axles being lost trying to take down a fone!  A quick and dirty way to open the
coin box is by using a shotgun.  In Detroit, after ecologists cleaned out a
municipal pond, they found 168 coin phone rifled.
In colder areas, such as Canada, some shrewd people tape up the fones using
duct tape, pour in water, and come back the next day when the water will have
froze thus expanding and cracking the fone open.
In one case, "unauthorized coin collectors" where caught when they brought
$6,000 in change to a bank and the bank became suspicious...
At any rate, the main lock is an eight level tumbler located on the right side
of the coin box.  This lock has 390,625 possible positions (5 ^ 8, since there
are 8 tumblers each with 5 possible positions) thus it is highly pick
resistant!  The lock is held in place by 4 screws.  If there is sufficient
clearance to the right of the fone, it is conceivable to punch out the screws
using the drilling pattern below (provided by Alexander Mundy in TAP #32):
   ====================================
                       !!        ^
                       !!        !
           ! 1- 3/16 " !!        !
           !<---   --->!!      1-1/2"
       --------------------      !
       !   !           !! !      !
       !  (+)         (+)-! -----------
    ---!               !! !      ^
    !  !               !! !      !
    !  !        (Z)    !! !      !
    !  !               !! !   2-3/16"
    ---!               !! !      !
       !  (+)         (+) !      !
       !               !! !      !
       -------------------- -----------
                       !!
                       !!
        (Z) Keyhole   (+) Screws
                       !!
    ===================================
After this is accomplished, the lock can be pushed backwards disengaging the
lock from the cover plate.  The four bolts of the cover plate can then be
retracted by turning the boltworks with a simple key in the shape of the hole
on the coin plate (see diagram below).  Of course, there are other methods and
drilling patterns.
:-------------------------------------:
                   _
                  ! !
                  ( )
                  !_!
               [roughly]
    Diagram of cover plate keyhole
:-------------------------------------:
The top cover uses a similar (but not as strong) locking method with the
keyhole depicted above on the top left side and a regular lock (probably
tumbler also) on the top right-hand side.  It is interesting to experiment with
the coin shute and the fortresses own "red box" (which Bell didn't have the
'balls' to color red).
Miscellaneous:
--------------
In a few areas (rural & Canada), post- pay service exists.  With this type of
service, the mouthpiece is cut off until the caller deposits money when the
called party answers.  This also allows for free calls to weather and other
DIAL-IT services!  Recently, 2600 magazine announced the CLEAR BOX which
consists of a telephone pickup coil and a small amp.  It is based on the
principal that the receiver is also a weak transmitter and that by amplifying
your signal you can talk via the transmitter thus avoiding costly telephone
charges!
Most fortresses are found in the 9xxx area.  Under former Bell areas, they
usually start at 98xx (right below the 99xx official series) and move downward.
Since the line, not the fone, determines whether or not a deposit must be made,
DTF & Charge-A-Call fones make great extensions!
Finally, fortress fones allow for a new hobby--instruction plate collecting.
All that is required is a flat-head screwdriver and a pair of needle-nose
pliers.  Simply use the screwdriver to lift underneath the plate so that you
can grab it with the pliers and yank downwards.  I would suggest covering the
tips of the pliers with electrical tape to prevent scratching.  Ten cent plates
are definitely becoming a "rarity!"
Fortress Security:
------------------
While a lonely fortress may seem the perfect target, beware!  The Gestapo has
been known to stake out fortresses for as long as 6 years according to the
Grass Roots Quarterly.  To avoid any problems, do not use the same fones
repeatedly for boxing, calling cards, & other experiments.  The telco knows how
much money should be in the coin box and when its not there they tend to get
perturbed (read:  pissed off).
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Disclaimer:
-----------
The preceding is intended for "information purposes only" and I do not advocate
that you participate in any subversive activities...
Coming sooner or later:
-----------------------
Part VII will deal with blue boxing.
References/Suggested Reading:
-----------------------------
Various hard-to-find Bell System publications.
"Alternate Method of Opening the Fortress Phone Coin Box," Alexander Mundy, TAP
#32.
"Build a T-Network for Fun & Profit," TAP #15.
"Coiners & Other Thieves," The Phone Book, J.  Edgar Hyde, pp 88-91.
"Fortress Fun-ding," TAP #66.
"The Green & Brown Box," Ted Veil & Nick Haflinger, TAP #68.
"Introducing the Clear Box!," 2600, July 1984.
"More Fortress Fun," TAP #49
"Notes on the Network," AT&T, 1980, [The definitive technical reference
guide!].
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
2600:
Box 752
Middle Island, NY 11953
Subscriptions:  $10/year (published monthly)
Last Issue (as of 10/27/84):  October 1984
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
TAP:
Room 603
147 W 42 Street
New York, NY 10036
Subscriptions:  $10/10 issues or so (published sporadically since 1971)
Last Issue (as of 10/27/84):  January/February 1984 [#90]
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
*****BIOC           (p) 1984 BIOC
*=$=*Agent          International, Ltd.
*****003
October 6, 1984
           <<=-FARGO 4A-=>>
 [Sherwood Forest ][ - (xxx) xxx-xxxx]
           [20 Megs On-Line]
PS Sysops of BBS's are welcome to use this material providing that nothing is
altered.
PPS Any and all threats, comments, corrections, suggestions, & subpoenas are
welcome.