THE XR-2207 CHIP IS A VOLTAGE-CONTROLLED OSCILLATOR AND A
14 PIN DEVICE THUS YOU MUST BE VERY CAREFUL WHEN SOLDERING
THE PARTS TO THIS DEVICE. IT IS A LITTLE DIFFICULT TO
ACTUALLY DRAW A SCHEMATIC ON AN 80 CHARACTER SCREEN USING
LIMITED GRAPHICS, BUT I WILL GIVE IT A TRY.
THIS IS A DIAGRAM OF HOW TO LOCATE THE DIFFERENT PINS ON
THE CHIP. PLEASE NOTICE THAT PIN ONE (1) IS THE CLOSET TO THE
NOTCH 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 (2) 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 SOLDERED TO PIN #11.
THE OTHER LEG OF R1 GOES TO PIN 1 OR TO THE D. 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
GROUND TO GROUND. PIN 14 IS THE OUTPUT AND THIS IS WHERE ONE
LEG C4 (C3 GOES TO THE OTHER VCO) IN SERIES WITH R3 (THE SAME
GOES FOR THE OTHER VCO) AND TO THE 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.
