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*** Solid State Silver Boxes *** Ma Bell is not the only one with standards! Just about every manufacturer of IC's that generate touch tones has also gone by the 16 key (8 tone) standard for Touch Tone pads. And it is even easier to convert a tone pad that uses an integrated circuit to generate the tones than converting a Ma Bell pad! It will help immensely if you have the schematic for the pad in question, or at least the pin-out diagram of the chip being used. Pin-outs can usually be obtained from the manufacturer or from an ECG, SK, GE or similiar semiconducter handbook (provided that manufacturer makes an equivalent for the chip in your pad). I'll use the Radio Shack CEX-4000 tone pad module for an example, even though it is probably almost the lousiest one you can buy, it is fairly typical and easily available. Take a look at the diagram or the pin-out of the chip. You should see two groups of pins, the rows tone pins and the column tone pins. These will be marked as R1,R2,R3,R4 and C1,C2,C3 (Radio Shack) or or X1,X2,X3 and Y1,Y2,Y3 etc. on others. At any rate, you should be able to distinguish which three pins control the columns and which four control the rows. If you're lucky, each group of rows and columns will be contiguous. Now look at the column pins, and you'll probably see an empty pin right next to them. This is the column pin for the 1633 hz tones. These chips usually achieve their switching by connecting a row pin with a column pin (that way they can use a very simple keyboard pad, unlike Ma Bell's complicated one). So all you have to do is take a SPDT switch and a few pieces of wire, cut the trace going the column 3 pin of the chip, attach a wire from the chip side of that cut to one end of the SPDT switch, a wire from the other side of the cut to the center of the SPDT switch, and finally, from the remaining contact on the SPDT switch, hook a wire to the previously identified pin C4 (Column 4). Now you have a "bank switching arrangement exactly like the one described in the previous bulletin for modifying a Ma Bell pad. If you can't get the schematics or the pin outs for your chip, don't despair. There is still hope for you! You just have to track the connections going from the pad's keys to the chip. Chances are you'll find that each row has a common trace, and so does each column (for those non-technical folks, a trace is a connection etched out on a circuit board). Just follow these to the chip, and make your own schematic up. Now take a look for that extra pin-- there should be one floating around right next to the column pins. It will be not be hooked up to anything else, that is, "hanging free". Drill a hole in the side of tonepad's case, and mount your switch. Radio Shack sells a nice microminiature switch that works excellently! (almost the only good thing I can say about Radio Shack in this article) Happy Phreaking..... Phincerely yours, Number Six. This bulletin describes how to take a standard touch tone keypad and convert it to a portable unit. In addition, I give the touch tone frequencies. First of all, the tones generated by a standard touch tone keypad (like one on a standard telephone) are not single tones, but a combination of two tones for each key pressed. Standard keypads normally generate 12 tone combinations [NOTE: actually, they are capable of generating 16 combinations, but normally do not have the extra 4 keys required. For more info on this, see the bulletin on silver boxes]. The power required by a keypad is about 25 volts, but they will work with as little as 15, thereby allowing the use of two 9-volt radio batteries. As you may have guessed, they are also designed to operate with a telephone type speaker (and phone line), and not the standard 8-ohm speaker which needs to be used for adequate volume. To accompolish this, we use a matching transformer, this is one of those miniature ones available at Radio Shack. Enough of the theory, now for the circuit. You will need: A touch tone keypad, A miniature 1000 to 8 ohm transformer (Radio Shack # 273-1380), A standard 8-ohm speaker, Two 9-volt radio batteries, Two 9-volt battery clips, A case to put it all in (optional) A few construction notes, I suggest that you solder and tape all connections. It is also important to read this entire bulletin before attempting to construct this. First, connect the RED wire of the transformer to either terminal on the speaker. Now connect the WHITE wire from the transformer to the other terminal on the speaker. Next, connect the RED (positive) wire of one battery clip to the black wire of the other battery clip. Now connect the the remaining RED wire on the second battery clip to the GREEN wire from the touch tone pad. Connect the BLUE wire from the touch tone pad to the ORANGE-and-BLACK striped wire from the touch tone pad. To these two wires, now connect the remaining black lead from first battery clip. You have now finished the power connection to the keypad. Connect the BLACK wire from the keypad to the BLUE wire on the transformer. Next connect the RED-and-GREEN striped wire from the keypad to the GREEN wire on the transformer. The BLACK wire on the transformer should not be connected to anything, along with quite a few wires from the keypad. The connection of the keypad is now complete. All you have to do is connect two nine volt batteries to the battery clips, and you'll be ready to go. You may want to mount it in a case of or easy portability. Note that the silver box modification CAN be made to this unit, allowing complete remote phreaking. When none of the buttons are pressed, this unit uses NO power, thereby eliminating the need for a power switch, and extending the life of the batteries. The following are the frequency combinations generated by each button on the keypad. KEY FREQ. #1 FREQ. #2 --- -------- -------- # 941 1477 * 941 1209 0 941 1336 1 697 1209 2 697 1336 3 697 1477 4 770 1209 5 770 1336 6 770 1477 7 852 1209 8 852 1336 9 852 1477 A 697 1633 B 770 1633 C 852 1633 D 941 1633 All frequencies are measured in Hertz Note that A,B,C and D are not normally present (except for silver boxes) That's all for now, leave all questions, comments, etc. in a message to me. DATA PHONE **********