This bulletin has been taken from the OSUNY files from 82/83 PLEASE NOTE THAT THIS BULLETIN IS FOR INFORMATION PURPOSES ONLY AND YOU SHOULD NOT ATTEMPT TO BUILD THIS DEVICE FOR USE IN ANY FRAUDULENT OR ILLEGAL ACT. M R. AMERICA KEY === First a few KEYS to the diagram: Cx is capacitor #x Denoted by: ---| |--- Px is Pot or Variable resistor #x Denoted by :/ \ /<-- \ Rx is resistor #x Denoted by /\/\/\/\ SCHEMATICS ========== The XR-2207 chip is a Voltage-Contr olled Oscillator and a 14 pin device thu s you must be very careful when soldering the parts to this device. It is a little dificult to actually draw a schematic on a 80 character scren using limited gra phics but will give it a try. TO GND_____________ | ___ C2 C3 ___ _||_ | | | _____|__9v+ | | | | ` ` ` ` ` ` ` | ---------------- --------------- | |7 6 5 4 3 2 1 | | | < | |8 9 10 11 12 13 14| | ---------------- --------------- | ` ` ` ` ` ` ` | | | | --| |--------| | | |C1 R2 | R1 | GND ______|___/\/\/\/\______|_ ____/\/\/\/\______| This is a diagram of how to locate the different pins on the chip please no tice that pin one is the closest to the n otch on top of the chip. The first thing we'll do is to connect power to the chip (remember that you need to build two of these to get a complete system) this is accomplished by connecting the positive wire of the battery lead to pin 1 one leg of R1 and R2 is solder to pin 11 the other leg of R1 goes to pin 1 or to the positive of the battery. The other leg of R2 goes to ground, C1 goes between pin 10 and ground. The timing capacitor or C2 goes between pins 2 and 3 of the chip pins 8 and 9 should be grounded to ground. Pin 14 is the output and this is where one leg of C4 (C3 goes on the other VCO) in series with R3(the same goes for the other VCO) and to one lead of the speaker. The trimmer pots P1 to P10 should be grouped in groups of 5 pots each . the way you group it is by soldering one end of the pot to each other leaving the wiper and the other end free. | This end goes to pin 6 of the chip | _____________|_____________ / / / / / \ \ \ \ \ /<- /<- /<- /<- /<- \ | \ | \ | \ | \ | / | / | / | / | / | | | | | | | | | | | P1 P2 P3 P4 P5 And finally this is the way each key should be wired. diode to Px ------>|-----| This is the contact of the |--------- \------ key to Px ------>|-----| | diode | ----- --- Ground - This may not be the best way to show the schematics but at least it is something. MR. AMERICA NOTE: This is for information ONLY please do not break any laws. Please direct any questions to the SYSOP or to Mr. America.