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QRSS DNA
June 6th, 2010

QRSS DNA

I'm still working on this project, and although progress is slow I'm learning a lot and the circuit is getting better with time. I'm still not yet ready to post the schematics, but you can get an idea of what's going on from the picture. It can handle 255 levels of frequency shift and has the ability to turn the tone on and off. 6 capacitors, 3 resistors, 4 transistors, a single inductor, and a micro-controller.

UPDATE I spotted myself on W4BHK's Grabber about 300 miles away...

#include <avr /io.h>
#include <util /delay.h>

char dotlen = 5;                              // ultimately the speeed of transmission
char call[] = {0, 1, 1, 1, 2, 0, 2, 1, 1, 0}; // 0 for space, 1 for dit, 2 for dah

void setfor(char freq, char ticks)
{
    OCR1A = freq;
    while (ticks > 0)
    {
        sleep();
        ticks--;
    }
}

void sleep()
{
    for (char i = 0; i < dotlen; i++)
    {
        _delay_loop_2(65000);
    }
}

void slideto(char freq, char ticks)
{
    freq = freq + 30;
    char step = 1;
    if (OCR1A > freq)
    {
        step = -1;
    }
    while (OCR1A != freq)
    {
        OCR1A += step;
        setfor(OCR1A, 1);
    }
    setfor(freq, ticks);
}

void DNA()
{
    char a[] = {4, 5, 5, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 8, 7, 7, 7, 7, 6, 6, 6, 5, 5, 4, 3, 3, 2, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 3, 3};
    char b[] = {1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 5, 5, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 8, 7, 7, 7, 7, 6, 6, 6, 5, 5, 4, 3, 3, 2, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0};
    for (char i = 0; i < sizeof(a); i++)
    {
        //slideto(a[i]*4,2);
        //slideto(b[i]*4,2);
        setfor(a[i] * 2 + 5, 10);
        setfor(b[i] * 2 + 5, 10);
    }
}

void ID()
{
    for (char i = 0; i < sizeof(call); i++)
    {
        setfor(10, 50);
        if (call[i] == 0)
        {
            setfor(10, 100);
        }
        if (call[i] == 1)
        {
            setfor(15, 100);
        }
        if (call[i] == 2)
        {
            setfor(15, 250);
        }
        setfor(10, 50);
    }
}

void ID2()
{
    for (char i = 0; i < sizeof(call); i++)
    {
        if (call[i] == 0)
        {
            ampOFF();
            setfor(10, 50);
        }
        if (call[i] == 1)
        {
            ampON();
            setfor(10, 100);
        }
        if (call[i] == 2)
        {
            ampON();
            setfor(13, 100);
        }
        ampOFF();
        setfor(OCR1A, 30);
    }
    ampON();
}

void ampON()
{
    PORTA |= (1 << PA7);
    PORTA |= (1 << PA0);
    PORTA &= ~(1 << PA1);
    _delay_loop_2(10000);
}
void ampOFF()
{
    PORTA &= ~(1 << PA7);
    PORTA |= (1 << PA1);
    PORTA &= ~(1 << PA0);
    _delay_loop_2(10000);
}

int main(void)
{
    DDRA = 255;
    OCR1A = 75;
    TCCR1A = 0x81;
    TCCR1B = 1;
    while (1)
    {
        ID2();
        ID();
        for (char i = 0; i < 3; i++)
        {
            DNA();
        }
    }
}
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