225 lines
11 KiB
Plaintext
225 lines
11 KiB
Plaintext
BUILDING A RED BOX
|
||
by JR "Bob" Dobbs
|
||
|
||
Essentially,the red box is a device used to fool the phone company into thinking
|
||
you are depositing coins into a payphone. Every time you drop a coin into a
|
||
payphone, the phone signals the type of coin inserted with one or more bursts of
|
||
a combination of 1700hz and 2200hz. The tone bursts are coded as follows:
|
||
Nickel:One 60 millisecond pulse
|
||
Dime :Two 60 millisecond pulses separated by 60 milliseconds
|
||
Quarter:Five 35 millisecond pulses separated by 35 milliseconds
|
||
|
||
HOW TO USE IT
|
||
-------------
|
||
Operation is simple. Simply dial a long distance number (some areas require you
|
||
to stick in a genuine nickel first), wait for the ACTS computer to demand your
|
||
cash, and press the "deposit" button on the red box for each coin you want to
|
||
simulate. The coin signals are coupled from the red box into the phone with a
|
||
small speaker held to the mouthpiece. For local calls, either you must first
|
||
deposit a genuine nickel before "simulating" more coins or place your call
|
||
through the operator with 0 + 7d. Use some care when the operator is on the
|
||
line--sometimes they catch on to your beeper ploy.
|
||
|
||
CIRCUIT OPERATION
|
||
-----------------
|
||
Each time the pushbutton is pressed, it triggers half of IC1, configured as a
|
||
monostable multivibrator to energize the rest of the circuit for a length of
|
||
time determined by the setting of the coin selector switch. This in turn starts
|
||
the other half of IC1, configured as an astable multivibrator, pulsing on and
|
||
off at regular intervals at a rate determined by the 50k pot between pins 12 and
|
||
13. The output of the astable thus alternately powers of IC2, configured as a
|
||
square wave oscillator, providing the required 1700hz and 2200hz to the op amp
|
||
which acts as a buffer to drive the speaker.
|
||
|
||
CONSTRUCTION
|
||
------------
|
||
Assemble the circuit as you wish. Component placement is not critical. I found
|
||
the easiest method was to use point-to-point wiring on a "universal" PC grid
|
||
board with solder ringed holes. Use sockets if you aren't a whiz with a
|
||
soldering iron. Be sure to leave easy access to the potentiometers for alignment
|
||
|
||
ALIGNMENT AND TESTING
|
||
---------------------
|
||
For alignment, a frequency counter and tiggered sweep oscilloscope are extremely
|
||
handy (but not absolutely necessary.) Install a temporary jumper from +9v
|
||
supply to pin 14 of IC2 and temporarily disconnect the 0.01uF capacitors from
|
||
pins 5 and 9 of IC2. Power up the circuit. Measuring the output from pin 5 of
|
||
IC2 with the frequency counter, adjust the 20k pot between pins 1 and 6 for an
|
||
output of 1700hz. Now adjust the 20k pot between pins 8 and 13 for an output of
|
||
2200hz from pin 9 of IC2. Remove the temporary jumper and re-attach the
|
||
capacitors to pins 5 and 9. (Note: if no frequency counter is available, the
|
||
outputs can be adjusted by ear one at a time by zero-beating the output tone
|
||
with a computer generated tone of known precision.) Next, temporarily disconnect
|
||
the wire between pins 5 and 10 of IC1. Set coin selector switch in the "N"
|
||
(nickel) position. With the oscilloscope measuring the output from pin 9 of IC1,
|
||
adjust the 50k pot between pins 12 and 13 of IC1 for output pulses of 60
|
||
millisecond duration. Reconnect the wire between pins 5 and 10. (Note: If no
|
||
scope is available, adjust the pulse rate by ear using computer generated tones
|
||
for comparison.) The remaining adjustments are made by ear. Leave the selector
|
||
switch in the "N" position. Adjust the 50k pot labelled "Dime" for a quick
|
||
double beep each time the pushbutton is pressed. Finally, set the selector to
|
||
"Quarter". Adjust the 50k pot labelled "Quarter" until exactly 5 very quick
|
||
beeps are heard for each button press. Don't worry if the quarter beeps sound
|
||
shorter and faster than the nickel and dime ones. They should be.
|
||
|
||
CONCLUSION
|
||
----------
|
||
If all went well to this point, your red box should be completely aligned and
|
||
functional. A final test should now be conducted from a payphone using the DATL
|
||
(dial access test line) coin test. Dial 09591230 and follow the computer
|
||
instructions using the red box at the proper prompts. The computer should
|
||
correctly identify all coins "simulated" and flag any anomalies. With a little
|
||
discretion, your red box should bring you many years of use. Remember, there's
|
||
no such thing as spare change.!
|
||
|
||
Parts list for Red Box
|
||
----------------------
|
||
Semiconductors
|
||
--------------
|
||
(2)556 dual timer
|
||
(1)741 Op Amp
|
||
(1)1N914 Switching Diode
|
||
|
||
Resistors
|
||
---------
|
||
(6)10k
|
||
(1)4.7k
|
||
(2)100k
|
||
(4)50k PC Mount Potentiometer
|
||
(2)20k Multi-Turn Potentiometer
|
||
|
||
Capacitors
|
||
----------
|
||
(10)0.01uF
|
||
(1)1.0uF
|
||
(2)10.0uF Electrolytic
|
||
|
||
Miscellaneous
|
||
-------------
|
||
(2)14 Pin Dip Socket
|
||
(1)8 Pin Dip Socket
|
||
(1)3-position Rotary Switch
|
||
(1)Momentary Push-Button Switch(normally open)
|
||
(1)SPST Toggle Switch
|
||
(1)Speaker or Telephone Earpiece Circuit Board
|
||
(1) Box
|
||
(1) 9v Battery Clip Mounting Hardware
|
||
|
||
SCHEMATIC DRAWING
|
||
-----------------
|
||
|
||
/ <20><><EFBFBD>S1<53><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ
|
||
+9v R1 R2 <20> <20> <20> <20>
|
||
<20><><EFBFBD><EFBFBD>C1<43><31><EFBFBD>Ĵ <20> R3 <20> <20>
|
||
<20> <20> <20><><EFBFBD>Ĵ <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>C2<43>@q S3 @n <20>
|
||
o <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ <20> R5 <20> @d <20> <20>
|
||
oĴ <20> 6 4 14 <20> R4 <20> <20> <20> <20><>Ŀ <20>
|
||
S2 o <20>Ĵ5 13<31><33><EFBFBD><EFBFBD>Ĵ g <20> <20><><EFBFBD>Ŀ <20> <20> <20>
|
||
<20> <20> <20> <20> <20> <20> <20> <20> R9<<3C><> <20>
|
||
g <20>Ĵ10 (IC1556) 8<>Ŀ R6<Ŀ <20> R8<<3C><><EFBFBD> <20> <20>
|
||
<20> <20> <20> <20> <20> <20> <20> <20> <20>
|
||
<20><><EFBFBD><EFBFBD>Ĵ9 12<31><32><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><>Ŀ <20> <20> <20>
|
||
<20> <20> 3 11 7 2 1 <20> C3 <20> <20> <20> <20> <20>
|
||
<20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> R7<<3C><> <20> <20> <20>
|
||
<20> <20> <20> <20> <20><>Ĵ g <20> <20> <20> <20>
|
||
<20> C4 C5 <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20>
|
||
<20> <20> <20> <20> C6 <20>
|
||
<20> <20> <20> <20> <20> <20>
|
||
<20> g g g g <20>
|
||
<20> <20>
|
||
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ <20>
|
||
R11 <20> R12 <20><><EFBFBD>Ŀ <20>
|
||
<20><>Ŀ <20> <20> <20> <20> v <20>
|
||
v <20> <20> <20><><EFBFBD><EFBFBD><EFBFBD>Ŀ <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>R13<31>Ŀ <20>
|
||
<20><><EFBFBD><EFBFBD>R10<31><30><EFBFBD>Ĵ <20> <20> <20> <20> <20> <20>
|
||
<20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ <20> <20>
|
||
<20> <20> 1 4 14 10 13 <20> <20> <20>
|
||
<20> <20> 8<><38><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ <20>
|
||
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ6 <20> <20> C12 <20>
|
||
<20> <20> <20> 12<31><32><EFBFBD><EFBFBD> <20> <20>
|
||
<20> <20>Ĵ2 IC2 556 <20> <20> <20>
|
||
C7 <20> <20> g <20>
|
||
<20> <20><>Ĵ3 11<31><31><EFBFBD><EFBFBD><EFBFBD>Ŀ <20>
|
||
<20> <20> <20> 7 5 9 <20> <20> <20>
|
||
g C8 <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> C11 <20>
|
||
<20> <20> C9 C10 <20> <20>
|
||
<20> <20> <20> <20> g <20>
|
||
g <20> <20><><EFBFBD><EFBFBD><EFBFBD> <20>
|
||
g <20> <20>
|
||
<20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||
<20> <20> <20>
|
||
<20> R14 <20>
|
||
<20> <20> <20>\ <20>
|
||
<20> <20> <20> \ <20>
|
||
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ij3 \<5C>
|
||
<20> <20> <20> 7 \
|
||
C13 R15 <20>IC3 \
|
||
<20> <20> <20>741 6/<2F><><EFBFBD><EFBFBD><EFBFBD>Ŀ
|
||
<20> <20> <20> 4 / <20>
|
||
<20> <20> <20> / <20>
|
||
g g <20><>Ĵ2 / <20> <20>
|
||
<20> <20>/ <20> <20>
|
||
<20> g <20>
|
||
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ
|
||
C14
|
||
<20>
|
||
Speaker
|
||
<20>
|
||
g
|
||
|
||
Schematic part variables list.
|
||
------------------------------
|
||
Resistors
|
||
---------
|
||
R1 - 10k
|
||
R2 - 10k
|
||
R3 - 4.7k
|
||
R4 - 10k
|
||
R5 - 10k
|
||
R6 - 50k
|
||
R7 - 50k
|
||
R8 - 50k
|
||
R9 - 50k
|
||
R10- 20k
|
||
R11- 10k
|
||
R12- 10k
|
||
R13- 20k
|
||
R14-100k
|
||
R15-100k
|
||
|
||
Capacitors
|
||
----------
|
||
C1 - 0.01uf
|
||
C2 - 1N914 switching Diode
|
||
C3 - 1.0uf
|
||
C4 - 0.01uf
|
||
C5 - 0.01uf
|
||
C6 - 10uf
|
||
C7 - 0.01uf
|
||
C8 - 0.01uf
|
||
C9 - 0.01uf
|
||
C10 - 0.01uf
|
||
C11 - 0.01uf
|
||
C12 - 0.01uf
|
||
C13 - 0.01uf
|
||
C14 - 10uf
|
||
|
||
Switches
|
||
--------
|
||
S1 - SPST toggle
|
||
S2 - Momentary push button N.O. labeled "Deposit"
|
||
S3 - 3-position rotary switch
|
||
|
||
Miscellaneous
|
||
-------------
|
||
g - Ground @q -
|
||
Label "quarter" @d -
|
||
Label "dime" @n -
|
||
Label "nickel"
|
||
|
||
Typed up by Sine Wave from an article which originally appeared in 2600 magazine.
|
||
The original contained several mistakes in the schematic drawing which I've
|
||
corrected. Hope this information enlightens you to new and exciting possibilities
|
||
via your local phone booth.
|
||
|