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TUCoPS :: Phreaking Technical System Info :: mabell2.dox

How Ma Bell Works 2

Disclaimer notice:

This file is presented as an Informational text file only.
Do not try any of the things mentioned as some are illegal
to try. The bbs operator takes no liabilty.

                   How Ma Bell Works - Part II

              "CANS" - Telephone Distribution Boxes

Basically, two types:

1> Large, rectangular silver box at the end of each street.

2> Black, round, or rectangular thing at every telephone pole.

Type 1 -   This is the case that takes the underground cable from 
the  bridge and runs it to the telephone pole cable (The  lowest, 
largest  one  on the telephone pole.)  The box is always  on  the 
pole nearest the briging head, where the line comes up.  Look for 
the 'Call before you Dig - Underground cable' stickers..

     The  case box is hinged,  so if you want to climb the  pole, 
you  can open it with no problems.   These usually have 2 rows of 
terminal sets. 

     You  could try to impersonate a Telco technician and  report 
the  number as 'new active' (giving a fake name and fake  report, 
etc.)   I  dont recommend this,  and it  probably  won't  (almost 
positively won't) work,  but this is basically what Telco linemen 

Type  2 - This is the splitter box for the group of houses around 
the  pole  (Usually  4 or 5 houses).   Use it  like  I  mentioned 
before.   The terminals (8 or so) will be in 2 horizontal rows of 
sets.   The  extra  wires  that  are  just  'hanging  there'  are 
provisions for extra lines to residences (1 extra line per house, 
thats  why  the insane charge for line #3!)  If its the  box  for 
your  house  also,  have fun and swap lines with  your  neighbor!  
'Piggyback'  them  and  wreak havoc  on  the  neighborhood  (It's 
eavesdropping  time...)  Again,  I don't recommend this,  and its 
difficult to do it correctly.  Moving right along...

                       DISTRIBUTION BOXES

     Found  outside the buliding (most often on the  right  side, 
but not always...   Just follow the wire from the telephone pole) 
or  in the basement.   It has a terminal for all the lines in the 
building.   Use it just like any other termination box as before. 
Usually says 'Bell system' or similar.  Has up to 20 terminals on 
it (usually.) the middle ones are grounds (forget   these).   The 
wires come from the cable to one row (usually the left one), with 
the other row of terminals for the other row of terminals for the 
building  fone wire pairs.   The ring (-) wire is usually the top 
terminal if the set in the row (1 of 10 or more),  and the tip is 
in the clamp/screw below it.  This can be reversed, but the cable 
pair is always terminated one-on-top-of-each- other,  not on  the 
one  next  to  it.  (I'm  not sure why the other  one  is  there, 
probably as aprovision for extra lines) Don't use it  though,  it 
is usually to close to the other terminals, and in my experiences 
you get a noisy connection.

Final note:  Almost every apartment, business, hotel, or anywhere 
there   is  more  than  2  lines  this  termination  lines   this 
termination method is used.  If you can master this type, you can 
be  in control of many things...   Look around in your area for a 
building  that  uses this type,  and practice hooking up  to  the 
line, etc.

As  an  added  help,here is the basic  'standard'  color-code  fo 
multiline terminals/wiring/etc...

Single line:  Red = Ring
            Green = Tip
           Yellow = Ground *

 *  (Connected  to  the ringer coil  in  individual  and  bridged 
    ringer   phones (Bell only)  Usually  connected to the  green 

Ring (-) = Red
           White/Red Stripe
           White/Orange Stripe
           Black/Yellow Stripe

Tip (+) =  Green (Sometimes
            yellow, see above.)
           White/Green Stripe
           White/Blue Stripe
           Black/White Stripe

Ground =   Black

                     RESIDENCE TERMINAL BOX

Small,  gray (can be either a rubber (Pacific Telephone) or  hard 
plastic  (AT & T) housing deal that connects the cable pair  from 
the  splitter box (See type 2,  above) on the pole to your  house 
wiring.  Only 2 (or 4, the 2 top terminals are hooked in parallel 
with the same line) terminals, and is very easy to use.  This can 
be  used to add more lines to your house or add an external  line 
outside the house.

                            TEST SETS

Well,  now  you  can  consider  yourself a minor  expert  on  the 
terminals and wiring of the local telephone network.  Now you can 
apply  it  to whatever you want to do..  Here's  another  helpful 

How  to  make  a Basic Test-Set and how to use it  to  dial  out, 
eavsdrop, or seriously tap and record line activity.

These  are  the  (usually) orange hand set fones  used  by  Telco 
technicians to test lines.   To make a very simple one,  take any 
Bell (or other,  but I recommend a good Bell fone like a princess 
or a trimline. gte flip fones work excllently, though..) fone and 
follow the instructions below.

Note:    A 'black box' type fone mod will let you tap into  their 
line,  and with the box o,  it's as if you werent there. they can 
recieve  calls and dial out,  and you can be listening the  whole 
time! very useful.  With the box off, you have a normal fone test 


A  basic black box works well with good results.   Take the cover 
off  the fone to expose the network box (Bell type  fones  only).  
The <RR> terminal should have a green wire going to it (orange or 
different  if  touch tone - doesnt matter,  its the same  thing). 
Disconnect the wire and connect it to one pole of an SPST switch.  
Connect  a  piece  of wire to the other pole of  the  switch  and 
connect it to the <RR> terminal.   Now take a 10k hm 1/2 watt 10% 
resistor  and  put  it  between the  <RR>  terminal  ad  the  <F> 
terminal,  which  should have a blue and a white wire going to it 
(different for touch tone).  It should look like this:

-----Blue wire----------<F>
----White wire-----!
              10k Resistor
--Green wire--     !----<RR>
              !    !

What  this  does in effect is keep the hookswitch  /  dial  pulse 
switch  (F to RR loop) open while holding the line high with  the 
resistor.   This gives the same voltage effect as if the fone was 
'on-hook',  while  the 10k ohms holds the voltage right above the 
'off hook' threshold (around 22 volts or so, as compared to 15-17  
or normal off hook 48 volts for normal 'on-hook'), giving

Continued In: Ma Bell Part II

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