296 lines
22 KiB
Plaintext
296 lines
22 KiB
Plaintext
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DTMF Generators, White Boxing, and Red Boxing
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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I've seen before me way too many fabrications of red boxes; the H/P
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community enjoys to talk about it a lot, and fantasize about its abilities.
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But seldom do I see an accurate example of any box construction. Perhaps
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I'm simply in the wrong circle? Nevertheless I did a little research on
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the actual structure of an DTMF Generator and on how to convert this into
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a red and white Box. 2600 Enterprises did have the BEST red box example to
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pass before me, however in Canada legislation differs quite a lot, and
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any kit or package that can be hacked is not tolerated; so therefore the
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famous Radio-Shack Pocket Dialer is not available here, and I would say
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many other places, such as Europe or Australia, where Radio Shack is not
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as widely established as in the USA. Our Radio Shacks are no bigger than a
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local corner candy store, and the only useful products they sell are
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calculators. Pathetic is the scene I run into everywhere I go in lovely
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Canada. So since the Radio-Shack Pocket Dialer WITH MEMORY is not available
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I guess we must build the actual device from scratch. It's fairly simple,
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and I've already succeeded in building the DTMF Generator. It's very
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easy -- it consists of one IC, a crystal to control the oscillator (in
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the IC) and a key-pad.
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The construction of the DTMF Tone Generator is perhaps the hardest part of
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this project, and yet that is quite fairly simple. Anyhow this project does
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require you to know the basics of kit building, and hopefully you know how
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to use a soldering iron, as you will need to solder the IC and Crystal onto
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a simple board. Now the DTMF tones are generated internally inside the IC,
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but the timing depends on an external crystal oscillator. And the only
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external component we have is the 3.579545 MHz crystal: right here we have
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a "white box," as a white box is suppose to generate the DTMF "Touch-Tone"
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tones. Now if we replaced the 3.579545 MHz crystal with an 6.5536 MHz one,
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our "*" key on the key-pad will actually be DARN close to 3900 Hertz, the
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EXACT frequency that a coin stimulates when being entered inside the pay-
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phone. So in reality instead of putting $0.25 you can put theses tones on
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the mouth piece and fool the Bell System.
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Brief Operation
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~~~~~~~~~~~~~~~
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When entering a $0.25 into a payphone the only way the phone company knows
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that you entered money by a tone which consists of a 700 Hz + 2200 Hz
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(3900 Hz) being flushed into the line. For quarter you will need 3900 Hz
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for 35ms in length and a pause for 35ms and then 3900hz for 35ms then a
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pause...etc. This must be produced exactly FIVE times, so you should have
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five tones of 3900hz of 35ms with pauses of 35ms between each.
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Our DTMF generator contains a ten-number memory. When we save a number into
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the DTMF memory and replay it, the redial timing will play the tone for
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72.3ms and pause for 72.3ms before going to the next tone and playing that
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for 72.3ms! Now the tones will be played at this speed ONLY with the
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3.579545 MHz crystal, as the crystal controls ALL LOGIC and TONE GENERATING
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TIMING! So when this is replaced with a 6.5535 Mhz crystal it naturally
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will be alot faster and the timing will be faster. As a matter of fact the
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timing is NOW 34.3ms! So anything redialled by the DTMF generator will come
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out at 34.3ms and a pause for 34.3ms. Our "*" key will also sound very
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close to the 700 + 2200 Hz, and therefore saving "*" 5 times in a memory
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and redialling it will result into sounding like a $0.25, all one has to do
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is put red box to the payphone mouth piece and the phone system will think
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you entered a valid $0.25.
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_____________________
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/ General Description \____________________________________________________
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Features
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~~~~~~~~
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<20> 2.5V-12V operation when generating tones, which is A LOT
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less voltage needed, compared to several white boxes I've
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seen which ask for 16V-24V.
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<20> Stores and auto-dials ten 16-digit numbers.
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<20> Last number redial.
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<20> Scratchpad, meaning number storage without dialling.
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<20> 14 Keys, separate storage and redial buttons.
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<20> 2-digit overwrite for PBX access codes.
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<20> Low harmonic distortion.
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<20> Single-contact or negative-common (2-of-8) key-pad inputs.
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Well, before we begin I must say that replacing the 3.57545 Mhz crystal
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with an 6.5536 will give us the 3900 Hertz tone ONLY by the "*" key. With
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this information the same is true for any key, on the keypad! In fact my
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calculations proved that in order to get an EXACT 3900 Hertz by the "*"
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key we would need a crystal of about 6.4857 Mhz. However chances of
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production of an 6.4857 Mhz crystal is asking for a little too much, so
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naturally we settle for the closest one possible to it; besides analog
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signals are quite difficult to simulate exactly, compared to digital,
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which is always exact!
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This IC is from "National Semiconductor Corporation" model number TP5660.
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Perhaps even the exact IC in the Radio-Shack Pocket Dialer with Memory,
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as the one without memory uses the TP5650 which is this exact IC but
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without memory! The Operating temperature is -30<33>C to +60<36>C. This IC
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looks like so:
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1<><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ16
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Vdd<64>Ĵ <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>TONE OUT
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2<> National <20>15
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Vm<56>Ĵ Semiconductor <20><><EFBFBD><EFBFBD>Row 5
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3<> (Linear <20>14
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Col 1<>Ĵ Databook) <20><><EFBFBD><EFBFBD>Row 1
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4<> <20>13
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Col 2<>Ĵ <20><><EFBFBD><EFBFBD>Row 2
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5<> TP5660 <20>12
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Col 3<>Ĵ <20><><EFBFBD><EFBFBD>Row 3
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6<> <20>11
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Vss<73>Ĵ <20><><EFBFBD><EFBFBD>Row 4
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7<> <20>10
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>OSC<53>IN<49>Ĵ <20><><EFBFBD><EFBFBD>MUTE OUT
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<EFBFBD><EFBFBD><EFBFBD> 3.579545 Mhz Crystal 8<> <20>9
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<EFBFBD><EFBFBD><EFBFBD> Control OSC. <20>OSC<53>OUT<55>Ĵ <20><><EFBFBD><EFBFBD>Col 4
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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Replace above with the below to have both Red & White Boxes in one.
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD> <20><><EFBFBD> 3.579545 Mhz
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<20><><EFBFBD> <20><><EFBFBD>
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<20> <20> <20> If you put a two-way switch you can switch from crystal,
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> to crystal, and you'll have a red and white (combo) box!
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Your new crystal should be 6.5536 for "*" Key
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Pin Description
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~~~~~~~~~~~~~~~
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Vdd (Pin 1): The positive supply to the device, referenced to
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Vss. A power-on reset circuit ensures correct operation
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following initial power-up.
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Vm (Pin 2): The negative terminal of the back-up battery for on-hook
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memory retention. A low-voltage detect circuit prevents
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missoperation of the circuit in the event of a reduction in
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the on-hook supply voltage below that required to retain
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stored data.
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COLUMN & ROW Scans (Pins 3, 4, 5, 9, 11, 12, 13, 14, 15): When no key is
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closed, pull-up resistors are active on COLUMN inputs and
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pull-down resistors are active on ROW inputs. Therefore
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after a key is pressed the ROW pull-down resistors cause a
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negative-true on COLUMN inputs (for standard telephone
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key-pads negative-common).
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Vss (pin 6): The negative supply to the device in the off-hook
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state.
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OSC IN, OSC OUT (pin 7, 8): All logic and tone generator timing is
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derived from the on-chip oscillator circuit.
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MUTE OUT (pin 10) This is a CMOS output which sinks current to
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Vss when no tones are being generated and sources current
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from Vdd when tones are being generated.
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TONE OUT (pin 16): This output is the open emitter of an NPN
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transistor. The other pin (collector) is connected with the
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Vdd.
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Well, this is the exact pin description according to the abilities and
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limitations of this IC. Now this Integrated Circuit (IC) was designed to
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be powered by the telephone line and a battery to keep the memory intact.
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Well, due to the fact that we are powering this circuit by battery you can
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feed both Vm and Vss to the same negative supply, the battery, of course.
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Now the MUTE OUT pin is perhaps also bothering you; well, this circuit was
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designed to drive a simple interface circuit to mute the receiver when any
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key is depressed. Again this is NOT needed as you will be connecting your
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DTMF generator to a small speaker rather than putting it directly into the
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line, as this circuit was designed for that, so all that MUTE does is when
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you start depressing keys it mutes of the receiver so that it will not
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interfere with other incoming sounds misstated as DTMF tones. However you
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can avoid adding a speaker by un-screwing the mouth piece and feed the
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TONE-OUT and Vdd supply directly into the conventional payphones, however
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this may attract unwanted glances, so you'll be better off with a
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speaker.
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The next part is about the key-pad, perhaps complex if you plan to design
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your own. Frankly, I found that time consuming; you can buy key-pads in
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several electronics stores, as Radio Shack, but I did find it in a local
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electronics store. Then again, if you have an old phone I guess you can
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take it from there. Now I must warn you there are TWO types of key-pads
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that are widely used, and both will work on this circuit, but you need
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to know which one you have in order to make corrections.
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The key-pad found in most telephones are what we call STANDARD KEYPADs.
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This has to do on the way the switch is connected inside.
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<20> Simply, when a key is depressed, it closes the
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row switch but also comes in contact with the
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<20>ٳ negative power supply. Thus we call this method
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<20>Ĵ <20> NEGATIVE-COMMON or/and standard key-pad.
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Vss<73>Ĵ
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Col
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<20> As you can see, this method consists of the row
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<20><>Ŀ and column coming to contact (a closing of a
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<20> switch). This type of keypad we call
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row SINGLE-CONTACT key-pad.
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<20>
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Col
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If you plan to build your key-pad certainly the single key-pad is the way
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to go, it's a lot simpler. So if your using a standard key-pad remember to
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connect the negative supply to the key-pad! All that's left now is to
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connect the key-pad to the circuit, very easy and fast; you just connect
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Col 1 to Col 1, Row 1 to Row 1, etc... You may notice that this is a
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military-style key-pad, as it includes the A, B, C, D keys which you don't
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find in your everyday phone key-pads. You really don't need them, so if
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you don't have them don't alarm yourself, just don't connect them!
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However you will need TWO extra keys, one for STORE command and the other
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for the REDIAL, so either add an extra key or switch or whatever you wish
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and connect it, like so.
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<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>Col 1
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<20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Col 2
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<20> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Col 3
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<20> <20> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Col 4
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŀ
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<20> 1 <20> 2 <20> 3 <20> A <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row 1
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ
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<20> 4 <20> 5 <20> 6 <20> B <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row 2
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ
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<20> 7 <20> 8 <20> 9 <20> C <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row 3
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ
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<20> * <20> 0 <20> # <20> D <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row 4
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ĵ
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<20>Store<72> <20>Redial<61> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Row 5
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<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>
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Ahh, congrads, your DTMF Generator is now completed! If you were like
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myself and added an extra switch to go from white box to red box mode,
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GREAT! The only difference is that a white box needs the 3.57545 Mhz
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crystal and the red box needs the corresponding crystal, so simply put a
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switch and move from mode to mode. Now for the red box to work we need five
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3900 hertz at 33 milliseconds apart and 33 milliseconds long, so you'll
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need to save your key five times in memory and then simply put the box to
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the mouthpiece end of the payphone and press the memory key, you have just
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enter $0.25 into the payphone.
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NOTE: I only have this working with the 6.5536 Mhz crystal. I cannot say
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that the timing interval will be exact with the other crystals; chances
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are that taking a crystal of 7.XXXXXX or 5.XXXXXX Mhz is simply too far
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from the 700 + 2200 hertz tone. Try to get the closest value to 6.50 Mhz.
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I didn't include the way to save the red box tone into the memory,
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as you get a nice little paper when you buy the IC, but in case you don't
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you first power up the unit, press "*" (or your valid red box tone key)
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five times and then you press STORE and a number in which to store it in.
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And to dial the stored key, press REDIAL and the number in which you
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stored the red box tone! Remember the NEW crystal should be installed at
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ALL times to generate the RED BOX tone! If you save the tone with your
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6.XXXX Mhz intact and redial it with the 3.57545 Mhz it will not work!
|
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|
|
|
|||
|
|
Lastly, I recommend an "A-Cut Crystal (NTSC TV color-burst)" for both the
|
|||
|
|
3.57545 and your red box crystal. Try local components stores. You should
|
|||
|
|
find the crystal, or else look around, ask around; I did leave you with a
|
|||
|
|
few references near here where I got most of my stuff so you can try them
|
|||
|
|
out if you can't find them on your own.
|
|||
|
|
|
|||
|
|
|
|||
|
|
REFERENCE
|
|||
|
|
Addison Ltd/Ltee
|
|||
|
|
8018 20th Avenue
|
|||
|
|
Montreal, Canada, H1Z-3S7
|
|||
|
|
tel: 1-514-376-1740
|
|||
|
|
|
|||
|
|
Active Electronic Components
|
|||
|
|
6080 Metropolitan East
|
|||
|
|
Montreal, Canada, H1S-1A9
|
|||
|
|
tel: 1-514-256-7538
|
|||
|
|
1-800-363-7601 (Outside Quebec)
|
|||
|
|
|
|||
|
|
Hamilton Avnet International Canada
|
|||
|
|
2570 Sabourin St., St-Laurent
|
|||
|
|
Montreal, Canada, H4S-1M2
|
|||
|
|
tel: 1-514-331-6443
|
|||
|
|
1-800-361-7129 (Outside Quebec)
|
|||
|
|
|
|||
|
|
National Semiconductors Corporation
|
|||
|
|
2900 Semiconductuctor Drive
|
|||
|
|
Santa Clara, California 95051, USA
|
|||
|
|
|
|||
|
|
ALSO: Try out Motorola and RCA dealers. They carry lots of
|
|||
|
|
crystals that go into TV decoders/scramblers, so there's a
|
|||
|
|
very good chance they should have it.
|
|||
|
|
|
|||
|
|
The crystals don't cost more than $1.00, kaypads can be bought for $0.75,
|
|||
|
|
PCBoard under $1.00, the IC goes for $2.00. The project should cost under
|
|||
|
|
$5 if you can find the supplies in local stores -- if I did in lonely
|
|||
|
|
Canada then you should have no trouble! If they don't have it, ask them to
|
|||
|
|
order it, if they ask "why?" tell them it's for a TV component, as TVs and
|
|||
|
|
related works like decoders and scramblers use NTSC TV color-burst
|
|||
|
|
crystals!
|
|||
|
|
|
|||
|
|
NOTE: For the next InfoJournal I should have a DTMF Generator for "Caller
|
|||
|
|
IDs" (yep, you can send your own DTMF Caller ID tones), and how the
|
|||
|
|
number/name is received. So call up your local BBS with Caller ID and make
|
|||
|
|
it display 666-6666 and logon as your favourite Death-Angel character name.
|
|||
|
|
Those interested in the actual project can contact myself anytime soon, of
|
|||
|
|
course you have must have a grasp of electronics!
|
|||
|
|
|