PLL (phase locked loop) board. A 9 volt transistor battery has its negative end grounded. The positive end goes through a switch to a point labeled plus 9 volts. This point goes through a 0.1 microfarad capacitor to ground. The plus 9 volt point also goes to the input terminal of a 78L05 three terminal regulator. The center terminal is grounded and the output goes to plus 5 volts. The output also goes through a 0.1 mike cap to ground. These two 0.1 caps must be as close to the regulator as physically possible. Pin 1 of an MC145170 IC goes to one side of a 10 Mc quartz crystal. The other side of the crystal goes to pin 2. A 470 k ohm resistor connects from pin 1 to pin 2. pins 1 and 2 each go through its own 27 pf cap to ground. Pin 3 is not connected, and pin 4 will be described later. Pin 5 of the IC goes to pin 5 of the diskey board plug. Pin 6 goes to pin 4 and pin 7 to pin 3. Pins 8, 9, 10, and 11 of the IC, are not connected. Pin 12 connects to ground. Pin 16 connects to plus 5 and there is a 0.1 mike cap physically close to the IC going from plus 5 to ground. Pin 13 goes through a 100 k ohm resistor than a 0.1 mike cap to ground. The junction of the resistor and cap goes to one end of another 100 k ohm resistor. The other end goes through a 68 k ohm resistor then a 1 mike cap to ground. The junction of the two resistors goes to pin 9 of the 74HC4046 IC. Pins 8 and 5 of this IC are grounded. Pin 16 connects to plus 5 volts. There is another 0.1 mike cap physically close to the IC going from plus 5 to ground. Pins 1, 2, 3, 10, 13, 14, and 15 are not connected. There is a 560 pf cap connected between pins 6 and 7. There is a 10 k ohm resistor from pin 11 to ground and a 47 k ohm resistor from pin 12 to ground. Pin 4 connects through a 0.1 mike cap then a 1 k ohm res back to pin 4 of the MC145170 IC. Pin 4 also connects through a 1 k ohm res to the base of a 2N3904 NPN transistor. The base also connects through a 390 ohm res to ground. The emitter goes through a 100 ohm res to ground. The collector goes through a 1 k ohm res to plus 9 volts. There is a 0.1 mike cap from plus 9 volts to ground which is physically close to the transistor. The collector goes through a 0.1 mike cap to the output. Pin 2 of the diskey plug is grounded and pin 1 goes to plus 5 volts. This plug is shown mating to a socket that is connected to the other end of the wires described on the diskey board schematic. The wire colors are, pin 1 red, 2 black, 3 yellow, 4 green, and 5 white. End verbal description.
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