Friday, 3 August 2018

Homebrew 80/40m SSB/CW Base Rig

Audio Amplifier


Another audio amplifier option.



Double Balanced Mixers





Plessey Bidirectional IF Amplifiers


Mic Amp



RF Power Amp



Low Pass Filters











Sunday, 17 June 2018

Portable 40m CW Transceiver



















#include <Wire.h>
#include <SPI.h>
#include <TM1637Display.h>
#include <si5351.h>
#include "LowPower.h"

const uint32_t bandStart = 7000000;     // start of 80m
const uint32_t bandEnd =   7400000;     // end of 80m
const uint32_t bandInit =  7025000;     // where to initially set the frequency
volatile long oldfreq = 0;
volatile long currentfreq = 0;
volatile int currentTime = 0;
volatile int previousTime = 0;
volatile int elapsed = 0;
volatile int QSK_Timer = 1000;
int PTT = 0;

volatile uint32_t freq = bandInit ;     // this is a variable (changes) - set it to the beginning of the band
volatile uint32_t radix = 1000;         // how much to change the frequency by, clicking the rotary encoder will change this.

volatile uint32_t LSB_IF_freq = 9011500;    // Crystal filter centre freq
volatile uint32_t LSB_BFO_freq = 9000000;   // Crystal filter centre freq

// Rotary encoder pins and other inputs
static const int rotBPin = 2;
static const int rotAPin = 3;
static const int pushPin = 4;
static const int KeyInput = 7;
static const int PTTOutput = 8;
static const int brightnessPin = A3;
static const int tunespeedLED = A2;
static const int gnd = 10;
static const int vcc = 11;
static const int DIO = 12;
static const int CLK = 13;

// Rotary encoder variables, used by interrupt routines
volatile int rotState = 0;
volatile int rotAval = 1;
volatile int rotBval = 1;


volatile long remainder = 0;
volatile long OnesHz = 0;
volatile long TensHz = 0;
volatile long HundredsHz = 0;
volatile long OneskHz = 0;
volatile long TenskHz = 0;
volatile long HundredskHz = 0;
volatile long OnesMHz = 0;
volatile long TensMHz = 0;
volatile int Brightness = 3;
volatile int batterySave = 0;

// Instantiate the Objects
TM1637Display display(CLK, DIO);    // CLK, DIO
Si5351 si5351;

void setup()
{
  // Set up frequency and radix switches
  pinMode(rotAPin, INPUT);
  pinMode(rotBPin, INPUT);
  pinMode(pushPin, INPUT);
  pinMode(brightnessPin, INPUT);
  pinMode(gnd, OUTPUT);
  pinMode(tunespeedLED, OUTPUT);
  pinMode(vcc, OUTPUT);
  pinMode(KeyInput, INPUT);
  pinMode(PTTOutput, OUTPUT);

  // Set up pull-up resistors on inputs
  digitalWrite(rotAPin, HIGH);
  digitalWrite(rotBPin, HIGH);
  digitalWrite(pushPin, HIGH);
  digitalWrite(brightnessPin, HIGH);
  digitalWrite(gnd, LOW);
  digitalWrite(vcc, HIGH);
  digitalWrite(tunespeedLED, LOW);
  digitalWrite(KeyInput, HIGH);
  digitalWrite(PTTOutput, LOW);

  // Set up interrupt pins
  attachInterrupt(digitalPinToInterrupt(rotAPin), ISRrotAChange, CHANGE);
  attachInterrupt(digitalPinToInterrupt(rotBPin), ISRrotBChange, CHANGE);

  // Initialize the display
  display.setBrightness(Brightness, true);
  UpdateDisplay();
  delay(1000);

  // Initialize the DDS
  si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0);
  si5351.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
  si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_8MA);
  si5351.drive_strength(SI5351_CLK1, SI5351_DRIVE_8MA);
  si5351.drive_strength(SI5351_CLK2, SI5351_DRIVE_8MA);
  si5351.set_freq(((8999300 + freq) * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);
  si5351.set_freq((LSB_BFO_freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK2);
}


void loop()
{
  //LowPower.idle(SLEEP_60MS, ADC_OFF, TIMER2_OFF, TIMER1_OFF, TIMER0_OFF, SPI_OFF, USART0_OFF, TWI_OFF);
  LowPower.idle(SLEEP_60MS, ADC_OFF, TIMER2_OFF, TIMER1_OFF, TIMER0_ON, SPI_OFF, USART0_OFF, TWI_OFF);

  if (digitalRead(KeyInput) == LOW)
  {
    si5351.output_enable(SI5351_CLK1, 1);
    SendFrequency();
  }

  if (digitalRead(KeyInput) == HIGH)
  {
    si5351.output_enable(SI5351_CLK1, 0);
  }

  currentfreq = getfreq();                // Interrupt safe method to get the current frequency

  if (currentfreq != oldfreq)
  {
    UpdateDisplay();
    SendFrequency();
    oldfreq = currentfreq;
  }

  if (digitalRead(brightnessPin) == LOW)
  {
    Brightness--;
    display.setBrightness(Brightness, true);
    if (Brightness == -1)
    {
      display.setBrightness(0, false);
      digitalWrite(tunespeedLED, LOW);
      batterySave = 1;
    }
    if (Brightness == -2)
    {
      Brightness = 3;
      batterySave = 0;
    }
    UpdateDisplay();
    delay(500);
  }

  if ((radix == 100) && (batterySave == 0))
    digitalWrite(tunespeedLED, HIGH);

  if (radix == 1000)
    digitalWrite(tunespeedLED, LOW);
}


void wakeUp()
{
  // Just a handler for the sleep pin interrupt.
}


long getfreq()
{
  long temp_freq;
  cli();
  temp_freq = freq;
  sei();
  return temp_freq;
}


// Interrupt routines
void ISRrotAChange()
{
  if (digitalRead(rotAPin))
  {
    rotAval = 1;
    UpdateRot();
  }
  else
  {
    rotAval = 0;
    UpdateRot();
  }
}


void ISRrotBChange()
{
  if (digitalRead(rotBPin))
  {
    rotBval = 1;
    UpdateRot();
  }
  else
  {
    rotBval = 0;
    UpdateRot();
  }
}


void UpdateRot()
{
  switch (rotState)
  {

    case 0:                                         // Idle state, look for direction
      if (!rotBval)
        rotState = 1;                               // CW 1
      if (!rotAval)
        rotState = 11;                              // CCW 1
      break;

    case 1:                                         // CW, wait for A low while B is low
      if (!rotBval)
      {
        if (!rotAval)
        {
          // either increment radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            if (radix == 1000)
              radix = 100;
            else if (radix == 100)
              radix = 1000;
          }
          else
          {
            freq = (freq + radix);
            if (freq > bandEnd)
              freq = bandEnd;
          }
          rotState = 2;                             // CW 2
        }
      }
      else if (rotAval)
        rotState = 0;                             // It was just a glitch on B, go back to start
      break;

    case 2:                                         // CW, wait for B high
      if (rotBval)
        rotState = 3;                               // CW 3
      break;

    case 3:                                         // CW, wait for A high
      if (rotAval)
        rotState = 0;                               // back to idle (detent) state
      break;

    case 11:                                        // CCW, wait for B low while A is low
      if (!rotAval)
      {
        if (!rotBval)
        {
          // either decrement radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            if (radix == 100)
              radix = 1000;
            else if (radix == 1000)
              radix = 100;
          }
          else
          {
            freq = (freq - radix);
            if (freq < bandStart)
              freq = bandStart;
          }
          rotState = 12;                            // CCW 2
        }
      }
      else if (rotBval)
        rotState = 0;                             // It was just a glitch on A, go back to start
      break;

    case 12:                                        // CCW, wait for A high
      if (rotAval)
        rotState = 13;                              // CCW 3
      break;

    case 13:                                        // CCW, wait for B high
      if (rotBval)
        rotState = 0;                               // back to idle (detent) state
      break;
  }
}


void UpdateDisplay()
{
  TensMHz = freq / 10000000;                                // TensMHz = 12345678 / 10000000 = 1
  remainder = freq - (TensMHz * 10000000);                  // remainder = 12345678 - 10000000 = 2345678
  OnesMHz = remainder / 1000000;                            // OnesMhz = 2345678 / 1000000 = 2
  remainder = remainder - (OnesMHz * 1000000);              // remainder = 2345678 - (2 * 1000000) = 345678
  HundredskHz = remainder / 100000;                         // HundredskHz = 345678 / 100000 = 3
  remainder = remainder - (HundredskHz * 100000);           // remainder = 345678 - (3 * 100000) = 45678
  TenskHz = remainder / 10000;                              // TenskHz = 45678 / 10000 = 4
  remainder = remainder - (TenskHz * 10000);                // remainder = 45678 - (4 * 10000) = 5678
  OneskHz = remainder / 1000;                               // OneskHz = 5678 / 1000 = 5
  remainder = remainder - (OneskHz * 1000);                 // remainder = 5678 - (5 * 1000) = 678
  HundredsHz = remainder / 100;                             // HundredsHz = 678 / 100 = 6
  remainder = remainder - (HundredsHz * 100);               // remainder = 678 - (6 * 100) = 78
  TensHz = remainder / 10;                                  // TensHz = 78 / 10 = 7
  remainder = remainder - (TensHz * 10);                    // remainder = 78 - (7 * 10) = 8
  OnesHz = remainder;                                       // OnesHz = 8

  display.showNumberDec(((1000 * HundredskHz) + ( 100 * TenskHz) + (10 * OneskHz) + HundredsHz), true);
}


void SendFrequency()
{
  // PA TX Drive
 si5351.set_freq((freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK1);

  // VFO
  //si5351.set_freq((freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);
  si5351.set_freq(((8999300 + freq) * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);


  // BFO
  si5351.set_freq((LSB_BFO_freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK2);
}









Tuesday, 20 March 2018

Homebrew SSB SDR Rig

Part 1. Quadrature Oscillator. See my ZL2CTM YouTube channel for accompanying video.



Code. This will be updated as additional SDR DSP functions are added.

#include <Wire.h>                          // I2C comms
#include <si5351.h>                        // Si5351 library
#include <LiquidCrystal_I2C.h>             // LCD library


// Define Constants and Vaviables
static const long bandStart = 1000000;     // start of HF band
static const long bandEnd =   30000000;    // end of HF band
static const long bandInit =  3690000;     // where to initially set the frequency
volatile long oldfreq = 0;
volatile long freq = bandInit ;
volatile long radix = 1000;                // how much to change the frequency by, clicking the rotary encoder will change this.
volatile int updatedisplay = 0;

// Rotary Encoder
static const int pushPin = 39;
static const int rotBPin = 36;
static const int rotAPin = 35;
volatile int rotState = 0;
volatile int rotAval = 1;
volatile int rotBval = 1;
volatile int rotAcc = 0;

// Instantiate the Objects
LiquidCrystal_I2C lcd(0x3F, 16, 2);       // set the LCD address to either 0x27 or 0x3F for a 16 chars and 2 line display
Si5351 si5351;


void setup()
{
  // Set up input switches
  pinMode(rotAPin, INPUT);
  pinMode(rotBPin, INPUT);
  pinMode(pushPin, INPUT);
  digitalWrite(rotAPin, HIGH);
  digitalWrite(rotBPin, HIGH);
  digitalWrite(pushPin, HIGH);

  // Set up interrupt pins
  attachInterrupt(digitalPinToInterrupt(rotAPin), ISRrotAChange, CHANGE);
  attachInterrupt(digitalPinToInterrupt(rotBPin), ISRrotBChange, CHANGE);

  // Initialise the lcd
  lcd.begin();
  lcd.backlight();

  // Initialise the DDS
  si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0);
  si5351.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
  si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_8MA);
  si5351.set_freq((freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);

  UpdateDisplay();
}


void loop()
{
  if (freq != oldfreq)
  {
    UpdateDisplay();
    SendFrequency();
    oldfreq = freq;
  }

  if (digitalRead(pushPin) == LOW)
  {
    delay(10);
    while (digitalRead(pushPin) == LOW)
    {
      if (updatedisplay == 1)
      {
        UpdateDisplay();
        updatedisplay = 0;
      }
    }
    delay(50);
  }
}


// Interrupt routines
void ISRrotAChange()
{
  if (digitalRead(rotAPin))
  {
    rotAval = 1;
    UpdateRot();
  }
  else
  {
    rotAval = 0;
    UpdateRot();
  }
}


void ISRrotBChange()
{
  if (digitalRead(rotBPin))
  {
    rotBval = 1;
    UpdateRot();
  }
  else
  {
    rotBval = 0;
    UpdateRot();
  }
}


void UpdateRot()
{
  switch (rotState)
  {

    case 0:                                         // Idle state, look for direction
      if (!rotBval)
        rotState = 1;                               // CW 1
      if (!rotAval)
        rotState = 11;                              // CCW 1
      break;

    case 1:                                         // CW, wait for A low while B is low
      if (!rotBval)
      {
        if (!rotAval)
        {
          // either increment radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1000000)
              radix = 100000;
            else if (radix == 100000)
              radix = 10000;
            else if (radix == 10000)
              radix = 1000;
            else if (radix == 1000)
              radix = 100;
            else if (radix == 100)
              radix = 10;
            else if (radix == 10)
              radix = 1;
            else
              radix = 1000000;
          }
          else
          {
            freq = (freq + radix);
            if (freq > bandEnd)
              freq = bandEnd;
          }
          rotState = 2;                             // CW 2
        }
      }
      else if (rotAval)
        rotState = 0;                               // It was just a glitch on B, go back to start
      break;

    case 2:                                         // CW, wait for B high
      if (rotBval)
        rotState = 3;                               // CW 3
      break;

    case 3:                                         // CW, wait for A high
      if (rotAval)
        rotState = 0;                               // back to idle (detent) state
      break;

    case 11:                                        // CCW, wait for B low while A is low
      if (!rotAval)
      {
        if (!rotBval)
        {
          // either decrement radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1)
              radix = 10;
            else if (radix == 10)
              radix = 100;
            else if (radix == 100)
              radix = 1000;
            else if (radix == 1000)
              radix = 10000;
            else if (radix == 10000)
              radix = 100000;
            else if (radix == 100000)
              radix = 1000000;
            else
              radix = 1;
          }
          else
          {
            freq = (freq - radix);
            if (freq < bandStart)
              freq = bandStart;
          }
          rotState = 12;                            // CCW 2
        }
      }
      else if (rotBval)
        rotState = 0;                               // It was just a glitch on A, go back to start
      break;

    case 12:                                        // CCW, wait for A high
      if (rotAval)
        rotState = 13;                              // CCW 3
      break;

    case 13:                                        // CCW, wait for B high
      if (rotBval)
        rotState = 0;                               // back to idle (detent) state
      break;
  }
}


void UpdateDisplay()
{
  lcd.cursor();                                     // Turn on the cursor
  lcd.setCursor(0, 0);
  lcd.print("        ");
  lcd.setCursor(0, 0);
  lcd.print(freq);
  lcd.setCursor(10, 0);
  lcd.print("ZL2CTM");

  lcd.setCursor(0, 1);
  lcd.print("        ");
  lcd.setCursor(0, 1);

  if (freq > 9999999)
  {
    if (radix == 1)
      lcd.setCursor(7, 0);
    if (radix == 10)
      lcd.setCursor(6, 0);
    if (radix == 100)
      lcd.setCursor(5, 0);
    if (radix == 1000)
      lcd.setCursor(4, 0);
    if (radix == 10000)
      lcd.setCursor(3, 0);
    if (radix == 100000)
      lcd.setCursor(2, 0);
    if (radix == 1000000)
      lcd.setCursor(1, 0);

  }
  if (freq <= 9999999)
  {
    if (radix == 1)
      lcd.setCursor(6, 0);
    if (radix == 10)
      lcd.setCursor(5, 0);
    if (radix == 100)
      lcd.setCursor(4, 0);
    if (radix == 1000)
      lcd.setCursor(3, 0);
    if (radix == 10000)
      lcd.setCursor(2, 0);
    if (radix == 100000)
      lcd.setCursor(1, 0);
    if (radix == 1000000)
      lcd.setCursor(0, 0);
  }
}



void SendFrequency()
{
  si5351.set_freq((freq * 4) * 100ULL, SI5351_PLL_FIXED, SI5351_CLK0);
}


*****************************************************************************

Dual Quadrature NE612 Direct Conversion Front End



Antenna RF Amplifier

Please note the collector inductor below is 1mH NOT 1uH




80m/20m Bandpass Filter



Audio Pass-through Test Code

#include <Wire.h>                          // I2C comms
#include <si5351.h>                        // Si5351 library
#include <LiquidCrystal_I2C.h>             // LCD library
#include <Audio.h>                         // Teensy audio library

// Define Constants and Vaviables
static const long bandStart = 1000000;     // start of HF band
static const long bandEnd =   30000000;    // end of HF band
static const long bandInit =  3690000;     // where to initially set the frequency
volatile long oldfreq = 0;
volatile long freq = bandInit ;
volatile long radix = 1000;                // how much to change the frequency by, clicking the rotary encoder will change this.
volatile int updatedisplay = 0;

// Rotary Encoder
static const int pushPin = 39;
static const int rotBPin = 36;
static const int rotAPin = 35;
volatile int rotState = 0;
volatile int rotAval = 1;
volatile int rotBval = 1;
volatile int rotAcc = 0;

// Instantiate the Objects
LiquidCrystal_I2C lcd(0x3F, 16, 2);       // Set the LCD address to either 0x27 or 0x3F for a 16 chars and 2 line display
Si5351 si5351;                            // The Si5351 DDS
AudioControlSGTL5000    audioShield;      // The Teensy audio CODEC on the audio shield


// Audio shield
AudioInputI2S           audioInput;                                   // What we call the input to the audio shield
AudioOutputI2S          audioOutput;                                  // What we call the output of the audio shield
AudioConnection         patchCord5(audioInput, 0, audioOutput, 0);    // Left channel in to left channel out
AudioConnection         patchCord10(audioInput, 1, audioOutput, 1);   // Right channel in to right channel out

void setup()
{
  // Setup input switches
  pinMode(rotAPin, INPUT);
  pinMode(rotBPin, INPUT);
  pinMode(pushPin, INPUT);
  digitalWrite(rotAPin, HIGH);
  digitalWrite(rotBPin, HIGH);
  digitalWrite(pushPin, HIGH);

  // Setup interrupt pins
  attachInterrupt(digitalPinToInterrupt(rotAPin), ISRrotAChange, CHANGE);
  attachInterrupt(digitalPinToInterrupt(rotBPin), ISRrotBChange, CHANGE);

  // Setup the lcd
  lcd.begin();
  lcd.backlight();

  // Setup the DDS
  si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0);
  si5351.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
  si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_8MA);
  si5351.set_freq((freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);

  // Setup the audio shield
  AudioNoInterrupts();
  AudioMemory(16);
  audioShield.enable();
  audioShield.inputSelect(AUDIO_INPUT_LINEIN);
  audioShield.volume(0.7);
  audioShield.unmuteLineout();
  AudioInterrupts();

  UpdateDisplay();
}


void loop()
{
  if (freq != oldfreq)
  {
    UpdateDisplay();
    SendFrequency();
    oldfreq = freq;
  }

  if (digitalRead(pushPin) == LOW)
  {
    delay(10);
    while (digitalRead(pushPin) == LOW)
    {
      if (updatedisplay == 1)
      {
        UpdateDisplay();
        updatedisplay = 0;
      }
    }
    delay(50);
  }
}


// Interrupt routines
void ISRrotAChange()
{
  if (digitalRead(rotAPin))
  {
    rotAval = 1;
    UpdateRot();
  }
  else
  {
    rotAval = 0;
    UpdateRot();
  }
}


void ISRrotBChange()
{
  if (digitalRead(rotBPin))
  {
    rotBval = 1;
    UpdateRot();
  }
  else
  {
    rotBval = 0;
    UpdateRot();
  }
}


void UpdateRot()
{
  switch (rotState)
  {

    case 0:                                         // Idle state, look for direction
      if (!rotBval)
        rotState = 1;                               // CW 1
      if (!rotAval)
        rotState = 11;                              // CCW 1
      break;

    case 1:                                         // CW, wait for A low while B is low
      if (!rotBval)
      {
        if (!rotAval)
        {
          // either increment radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1000000)
              radix = 100000;
            else if (radix == 100000)
              radix = 10000;
            else if (radix == 10000)
              radix = 1000;
            else if (radix == 1000)
              radix = 100;
            else if (radix == 100)
              radix = 10;
            else if (radix == 10)
              radix = 1;
            else
              radix = 1000000;
          }
          else
          {
            freq = (freq + radix);
            if (freq > bandEnd)
              freq = bandEnd;
          }
          rotState = 2;                             // CW 2
        }
      }
      else if (rotAval)
        rotState = 0;                               // It was just a glitch on B, go back to start
      break;

    case 2:                                         // CW, wait for B high
      if (rotBval)
        rotState = 3;                               // CW 3
      break;

    case 3:                                         // CW, wait for A high
      if (rotAval)
        rotState = 0;                               // back to idle (detent) state
      break;

    case 11:                                        // CCW, wait for B low while A is low
      if (!rotAval)
      {
        if (!rotBval)
        {
          // either decrement radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1)
              radix = 10;
            else if (radix == 10)
              radix = 100;
            else if (radix == 100)
              radix = 1000;
            else if (radix == 1000)
              radix = 10000;
            else if (radix == 10000)
              radix = 100000;
            else if (radix == 100000)
              radix = 1000000;
            else
              radix = 1;
          }
          else
          {
            freq = (freq - radix);
            if (freq < bandStart)
              freq = bandStart;
          }
          rotState = 12;                            // CCW 2
        }
      }
      else if (rotBval)
        rotState = 0;                               // It was just a glitch on A, go back to start
      break;

    case 12:                                        // CCW, wait for A high
      if (rotAval)
        rotState = 13;                              // CCW 3
      break;

    case 13:                                        // CCW, wait for B high
      if (rotBval)
        rotState = 0;                               // back to idle (detent) state
      break;
  }
}


void UpdateDisplay()
{
  lcd.cursor();                                     // Turn on the cursor
  lcd.setCursor(0, 0);
  lcd.print("        ");
  lcd.setCursor(0, 0);
  lcd.print(freq);
  lcd.setCursor(10, 0);
  lcd.print("ZL2CTM");

  lcd.setCursor(0, 1);
  lcd.print("        ");
  lcd.setCursor(0, 1);

  if (freq > 9999999)
  {
    if (radix == 1)
      lcd.setCursor(7, 0);
    if (radix == 10)
      lcd.setCursor(6, 0);
    if (radix == 100)
      lcd.setCursor(5, 0);
    if (radix == 1000)
      lcd.setCursor(4, 0);
    if (radix == 10000)
      lcd.setCursor(3, 0);
    if (radix == 100000)
      lcd.setCursor(2, 0);
    if (radix == 1000000)
      lcd.setCursor(1, 0);

  }
  if (freq <= 9999999)
  {
    if (radix == 1)
      lcd.setCursor(6, 0);
    if (radix == 10)
      lcd.setCursor(5, 0);
    if (radix == 100)
      lcd.setCursor(4, 0);
    if (radix == 1000)
      lcd.setCursor(3, 0);
    if (radix == 10000)
      lcd.setCursor(2, 0);
    if (radix == 100000)
      lcd.setCursor(1, 0);
    if (radix == 1000000)
      lcd.setCursor(0, 0);
  }
}



void SendFrequency()
{
  si5351.set_freq((freq * 4) * 100ULL, SI5351_PLL_FIXED, SI5351_CLK0);
}

************************************************************************

AF Amplifier




Receive Test Code

// Libraries
#include <Wire.h>                          // I2C comms library
#include <si5351.h>                        // Si5351Jason library
#include <LiquidCrystal_I2C.h>             // LCD library
#include <Audio.h>                         // Teensy audio library

// Number of Filter Coefficients
#define NO_HILBERT_COEFFS 70               // Used to define the Hilbert transform filter arrays. More typical than 'const int'.

// Define Constants and Vaviables
static const long bandStart = 1000000;     // start of HF band
static const long bandEnd =   30000000;    // end of HF band
static const long bandInit =  3690000;     // where to initially set the frequency
volatile long oldfreq = 0;
volatile long freq = bandInit ;
volatile long radix = 1000;                // how much to change the frequency by clicking the rotary encoder will change this.
volatile int updatedisplay = 0;

// Rotary Encoder
static const int pushPin = 39;
static const int rotBPin = 36;
static const int rotAPin = 35;
volatile int rotState = 0;
volatile int rotAval = 1;
volatile int rotBval = 1;
volatile int rotAcc = 0;


// Iowa Hills Hilbert transform filter coefficients
const short Hilbert_Plus_45_Coeffs[NO_HILBERT_COEFFS] = {
  (short)(32768 * -0.000287988910943357),
  (short)(32768 * -0.000383511439791303),
  (short)(32768 * -0.000468041804899774),
  (short)(32768 * -0.000529324432676899),
  (short)(32768 * -0.000569479602046985),
  (short)(32768 * -0.000616670267768531),
  (short)(32768 * -0.000731530748681977),
  (short)(32768 * -0.001002372095321225),
  (short)(32768 * -0.001525299390682192),
  (short)(32768 * -0.002370114347025230),
  (short)(32768 * -0.003539247773172147),
  (short)(32768 * -0.004932965382552984),
  (short)(32768 * -0.006337182914262393),
  (short)(32768 * -0.007448193692118567),
  (short)(32768 * -0.007940501940620482),
  (short)(32768 * -0.007570802072162988),
  (short)(32768 * -0.006296120449841751),
  (short)(32768 * -0.004371955618154949),
  (short)(32768 * -0.002391875073164555),
  (short)(32768 * -0.001236984700413469),
  (short)(32768 * -0.001922560128827416),
  (short)(32768 * -0.005356720327533458),
  (short)(32768 * -0.012055656297010635),
  (short)(32768 * -0.021882952959947619),
  (short)(32768 * -0.033888748300090733),
  (short)(32768 * -0.046312736456333638),
  (short)(32768 * -0.056783367797647665),
  (short)(32768 * -0.062699937453677912),
  (short)(32768 * -0.061735375084135742),
  (short)(32768 * -0.052358513976237808),
  (short)(32768 * -0.034257179158167443),
  (short)(32768 * -0.008554500746482946),
  (short)(32768 * 0.022249911747384360),
  (short)(32768 * 0.054622962942346594),
  (short)(32768 * 0.084568844473140448),
  (short)(32768 * 0.108316122839950818),
  (short)(32768 * 0.122979341462627859),
  (short)(32768 * 0.127056096658453188),
  (short)(32768 * 0.120656295327679283),
  (short)(32768 * 0.105420364259485699),
  (short)(32768 * 0.084152608145489444),
  (short)(32768 * 0.060257510644444748),
  (short)(32768 * 0.037105711921879434),
  (short)(32768 * 0.017464092086704748),
  (short)(32768 * 0.003100559033325746),
  (short)(32768 * -0.005373489802481697),
  (short)(32768 * -0.008418211280310166),
  (short)(32768 * -0.007286730644726664),
  (short)(32768 * -0.003638388931163832),
  (short)(32768 * 0.000858330713630433),
  (short)(32768 * 0.004847436504682235),
  (short)(32768 * 0.007476399317750315),
  (short)(32768 * 0.008440227567663121),
  (short)(32768 * 0.007898970420636600),
  (short)(32768 * 0.006314366257036837),
  (short)(32768 * 0.004261033495040515),
  (short)(32768 * 0.002261843500794377),
  (short)(32768 * 0.000680212977485724),
  (short)(32768 * -0.000319493110301691),
  (short)(32768 * -0.000751893569425181),
  (short)(32768 * -0.000752248417868501),
  (short)(32768 * -0.000505487955986662),
  (short)(32768 * -0.000184645628631330),
  (short)(32768 * 0.000087913008490067),
  (short)(32768 * 0.000253106348867209),
  (short)(32768 * 0.000306473486382603),
  (short)(32768 * 0.000277637042003169),
  (short)(32768 * 0.000207782317481292),
  (short)(32768 * 0.000132446796990356),
  (short)(32768 * 0.000072894261560354)
};

// Iowa Hills Hilbert transform filter coefficients
const short Hilbert_Minus_45_Coeffs[NO_HILBERT_COEFFS] = {
  (short)(32768 * -0.000072894261560345),
  (short)(32768 * -0.000132446796990344),
  (short)(32768 * -0.000207782317481281),
  (short)(32768 * -0.000277637042003168),
  (short)(32768 * -0.000306473486382623),
  (short)(32768 * -0.000253106348867259),
  (short)(32768 * -0.000087913008490148),
  (short)(32768 * 0.000184645628631233),
  (short)(32768 * 0.000505487955986583),
  (short)(32768 * 0.000752248417868491),
  (short)(32768 * 0.000751893569425298),
  (short)(32768 * 0.000319493110301983),
  (short)(32768 * -0.000680212977485245),
  (short)(32768 * -0.002261843500793748),
  (short)(32768 * -0.004261033495039842),
  (short)(32768 * -0.006314366257036280),
  (short)(32768 * -0.007898970420636345),
  (short)(32768 * -0.008440227567663343),
  (short)(32768 * -0.007476399317751102),
  (short)(32768 * -0.004847436504683540),
  (short)(32768 * -0.000858330713632029),
  (short)(32768 * 0.003638388931162351),
  (short)(32768 * 0.007286730644725833),
  (short)(32768 * 0.008418211280310565),
  (short)(32768 * 0.005373489802483816),
  (short)(32768 * -0.003100559033321630),
  (short)(32768 * -0.017464092086698697),
  (short)(32768 * -0.037105711921871905),
  (short)(32768 * -0.060257510644436532),
  (short)(32768 * -0.084152608145481672),
  (short)(32768 * -0.105420364259479538),
  (short)(32768 * -0.120656295327675800),
  (short)(32768 * -0.127056096658453216),
  (short)(32768 * -0.122979341462631633),
  (short)(32768 * -0.108316122839958146),
  (short)(32768 * -0.084568844473150454),
  (short)(32768 * -0.054622962942358168),
  (short)(32768 * -0.022249911747396132),
  (short)(32768 * 0.008554500746472333),
  (short)(32768 * 0.034257179158159054),
  (short)(32768 * 0.052358513976232306),
  (short)(32768 * 0.061735375084133286),
  (short)(32768 * 0.062699937453678217),
  (short)(32768 * 0.056783367797650072),
  (short)(32768 * 0.046312736456337288),
  (short)(32768 * 0.033888748300094730),
  (short)(32768 * 0.021882952959951244),
  (short)(32768 * 0.012055656297013388),
  (short)(32768 * 0.005356720327535105),
  (short)(32768 * 0.001922560128828006),
  (short)(32768 * 0.001236984700413229),
  (short)(32768 * 0.002391875073163812),
  (short)(32768 * 0.004371955618154038),
  (short)(32768 * 0.006296120449840938),
  (short)(32768 * 0.007570802072162439),
  (short)(32768 * 0.007940501940620253),
  (short)(32768 * 0.007448193692118624),
  (short)(32768 * 0.006337182914262643),
  (short)(32768 * 0.004932965382553323),
  (short)(32768 * 0.003539247773172483),
  (short)(32768 * 0.002370114347025498),
  (short)(32768 * 0.001525299390682370),
  (short)(32768 * 0.001002372095321316),
  (short)(32768 * 0.000731530748682004),
  (short)(32768 * 0.000616670267768521),
  (short)(32768 * 0.000569479602046963),
  (short)(32768 * 0.000529324432676881),
  (short)(32768 * 0.000468041804899765),
  (short)(32768 * 0.000383511439791304),
  (short)(32768 * 0.000287988910943362)
};


// Instantiate the Objects
LiquidCrystal_I2C lcd(0x3F, 16, 2);       // Name for the LCD. Set the LCD address to either 0x27 or 0x3F for a 16 chars and 2 line display
Si5351 si5351;                            // Name for the Si5351 DDS
AudioControlSGTL5000    audioShield;      // Name for the Teensy audio CODEC on the audio shield

// Audio shield
AudioInputI2S           audioInput;                                           // Name for the input to the audio shield
AudioOutputI2S          audioOutput;                                          // Name for the output of the audio shield
// Receiver
AudioFilterFIR          RX_Hilbert_Plus_45;                                   // Name for the RX +45 Hilbert transform
AudioFilterFIR          RX_Hilbert_Minus_45;                                  // Name for the RX +45 Hilbert transform
AudioMixer4             RX_Summer;                                            // Name for the RX summer

// Audio connections
AudioConnection         patchCord5(audioInput, 0, RX_Hilbert_Plus_45, 0);     // Left channel in Hilbert transform +45
AudioConnection         patchCord10(audioInput, 1, RX_Hilbert_Minus_45, 0);   // Right channel in Hilbert transform -45
AudioConnection         patchCord15(RX_Hilbert_Plus_45, 0, RX_Summer, 0);     // Hilbert transform +45 to receiver summer
AudioConnection         patchCord20(RX_Hilbert_Minus_45, 0, RX_Summer, 1);    // Hilbert transform -45 to receiver summer
AudioConnection         patchCord25(RX_Summer, 0, audioOutput, 0);            // Receiver summer to receiver LPF


void setup()
{
  // Setup input switches
  pinMode(rotAPin, INPUT);
  pinMode(rotBPin, INPUT);
  pinMode(pushPin, INPUT);
  digitalWrite(rotAPin, HIGH);
  digitalWrite(rotBPin, HIGH);
  digitalWrite(pushPin, HIGH);

  // Setup interrupt pins
  attachInterrupt(digitalPinToInterrupt(rotAPin), ISRrotAChange, CHANGE);
  attachInterrupt(digitalPinToInterrupt(rotBPin), ISRrotBChange, CHANGE);

  // Setup the lcd
  lcd.begin();
  lcd.backlight();

  // Setup the DDS
  si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0);
  si5351.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
  si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_8MA);
  si5351.set_freq((freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);

  // Setup the audio shield
  AudioNoInterrupts();
  AudioMemory(16);
  audioShield.enable();
  audioShield.volume(0.7);            // Constant. Use external volume control on the audio amp
  AudioInterrupts();

  // Setup transceiver mode
  Turn_On_Receiver();
  UpdateDisplay();
}

void loop()
{
  if (freq != oldfreq)                // Check to see if the frequency has changed. If so, update everything.
  {
    UpdateDisplay();
    SendFrequency();
    oldfreq = freq;
  }

  if (digitalRead(pushPin) == LOW)    // Update cursor, but also stop it from flickering
  {
    delay(10);
    while (digitalRead(pushPin) == LOW)
    {
      if (updatedisplay == 1)
      {
        UpdateDisplay();
        updatedisplay = 0;
      }
    }
    delay(50);
  }
}


void Turn_On_Receiver()
{
  AudioNoInterrupts();
  audioShield.inputSelect(AUDIO_INPUT_LINEIN);
  audioShield.lineInLevel(5);                                               // Default is 5
  audioShield.unmuteHeadphone();
  RX_Hilbert_Plus_45.begin(Hilbert_Plus_45_Coeffs, NO_HILBERT_COEFFS);
  RX_Hilbert_Minus_45.begin(Hilbert_Minus_45_Coeffs, NO_HILBERT_COEFFS);

  if (freq <= 9999999)          // LSB
  {
    RX_Summer.gain(0, 1);
    RX_Summer.gain(1, -1);
  }
  if (freq > 9999999)           // USB
  {
    RX_Summer.gain(0, 1);
    RX_Summer.gain(1, 1);
  }

  AudioInterrupts();
}


// Interrupt routines
void ISRrotAChange()
{
  if (digitalRead(rotAPin))
  {
    rotAval = 1;
    UpdateRot();
  }
  else
  {
    rotAval = 0;
    UpdateRot();
  }
}


void ISRrotBChange()
{
  if (digitalRead(rotBPin))
  {
    rotBval = 1;
    UpdateRot();
  }
  else
  {
    rotBval = 0;
    UpdateRot();
  }
}


void UpdateRot()
{
  switch (rotState)
  {

    case 0:                                         // Idle state, look for direction
      if (!rotBval)
        rotState = 1;                               // CW 1
      if (!rotAval)
        rotState = 11;                              // CCW 1
      break;

    case 1:                                         // CW, wait for A low while B is low
      if (!rotBval)
      {
        if (!rotAval)
        {
          // either increment radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1000000)
              radix = 100000;
            else if (radix == 100000)
              radix = 10000;
            else if (radix == 10000)
              radix = 1000;
            else if (radix == 1000)
              radix = 100;
            else if (radix == 100)
              radix = 10;
            else if (radix == 10)
              radix = 1;
            else
              radix = 1000000;
          }
          else
          {
            freq = (freq + radix);
            if (freq > bandEnd)
              freq = bandEnd;
          }
          rotState = 2;                             // CW 2
        }
      }
      else if (rotAval)
        rotState = 0;                               // It was just a glitch on B, go back to start
      break;

    case 2:                                         // CW, wait for B high
      if (rotBval)
        rotState = 3;                               // CW 3
      break;

    case 3:                                         // CW, wait for A high
      if (rotAval)
        rotState = 0;                               // back to idle (detent) state
      break;

    case 11:                                        // CCW, wait for B low while A is low
      if (!rotAval)
      {
        if (!rotBval)
        {
          // either decrement radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1)
              radix = 10;
            else if (radix == 10)
              radix = 100;
            else if (radix == 100)
              radix = 1000;
            else if (radix == 1000)
              radix = 10000;
            else if (radix == 10000)
              radix = 100000;
            else if (radix == 100000)
              radix = 1000000;
            else
              radix = 1;
          }
          else
          {
            freq = (freq - radix);
            if (freq < bandStart)
              freq = bandStart;
          }
          rotState = 12;                            // CCW 2
        }
      }
      else if (rotBval)
        rotState = 0;                               // It was just a glitch on A, go back to start
      break;

    case 12:                                        // CCW, wait for A high
      if (rotAval)
        rotState = 13;                              // CCW 3
      break;

    case 13:                                        // CCW, wait for B high
      if (rotBval)
        rotState = 0;                               // back to idle (detent) state
      break;
  }
}


void UpdateDisplay()
{
  lcd.cursor();                                     // Turn on the cursor
  lcd.setCursor(0, 0);
  lcd.print("        ");
  lcd.setCursor(0, 0);
  lcd.print(freq);
  lcd.setCursor(10, 0);
  lcd.print("ZL2CTM");

  lcd.setCursor(0, 1);
  lcd.print("        ");
  lcd.setCursor(0, 1);

  if (freq > 9999999)
  {
    if (radix == 1)
      lcd.setCursor(7, 0);
    if (radix == 10)
      lcd.setCursor(6, 0);
    if (radix == 100)
      lcd.setCursor(5, 0);
    if (radix == 1000)
      lcd.setCursor(4, 0);
    if (radix == 10000)
      lcd.setCursor(3, 0);
    if (radix == 100000)
      lcd.setCursor(2, 0);
    if (radix == 1000000)
      lcd.setCursor(1, 0);

  }
  if (freq <= 9999999)
  {
    if (radix == 1)
      lcd.setCursor(6, 0);
    if (radix == 10)
      lcd.setCursor(5, 0);
    if (radix == 100)
      lcd.setCursor(4, 0);
    if (radix == 1000)
      lcd.setCursor(3, 0);
    if (radix == 10000)
      lcd.setCursor(2, 0);
    if (radix == 100000)
      lcd.setCursor(1, 0);
    if (radix == 1000000)
      lcd.setCursor(0, 0);
  }
}


void SendFrequency()
{
  si5351.set_freq((freq * 4) * 100ULL, SI5351_PLL_FIXED, SI5351_CLK0);

}

***************************************************************

Transmit Test Configuration








Transmit Test Code 

Note, the formatting has been messed up from cutting and pasting. Use auto format after pasting into the Arduino IDE) 


// Libraries
#include <Wire.h>                          // I2C comms library
#include <si5351.h>                        // Si5351Jason library
#include <LiquidCrystal_I2C.h>             // LCD library
#include <Audio.h>                         // Teensy audio library

// Number of Filter Coefficients
#define NO_HILBERT_COEFFS 70               // Used to define the Hilbert transform filter arrays. More typical than 'const int'.

// Define Constants and Vaviables
static const long bandStart = 1000000;     // start of HF band
static const long bandEnd =   30000000;    // end of HF band
static const long bandInit =  3690000;     // where to initially set the frequency
//static const long bandInit =  14190000;  // where to initially set the frequency
volatile long oldfreq = 0;
volatile long freq = bandInit ;
volatile long radix = 1000;                // how much to change the frequency by clicking the rotary encoder will change this.
volatile int updatedisplay = 0;

static const int Mic_Gain = 0;            // Range is 0-63dB.
static const int Lineout_Gain = 20;        // Range is 13-31. 13 = 3.16 Vp-p, 31 = 1.16 Vp-p

// Rotary Encoder
static const int pushPin = 39;
static const int rotBPin = 36;
static const int rotAPin = 35;
volatile int rotState = 0;
volatile int rotAval = 1;
volatile int rotBval = 1;
volatile int rotAcc = 0;


// Iowa Hills Hilbert transform filter coefficients
const short Hilbert_Plus_45_Coeffs[NO_HILBERT_COEFFS] = {
  (short)(32768 * -0.000287988910943357),
  (short)(32768 * -0.000383511439791303),
  (short)(32768 * -0.000468041804899774),
  (short)(32768 * -0.000529324432676899),
  (short)(32768 * -0.000569479602046985),
  (short)(32768 * -0.000616670267768531),
  (short)(32768 * -0.000731530748681977),
  (short)(32768 * -0.001002372095321225),
  (short)(32768 * -0.001525299390682192),
  (short)(32768 * -0.002370114347025230),
  (short)(32768 * -0.003539247773172147),
  (short)(32768 * -0.004932965382552984),
  (short)(32768 * -0.006337182914262393),
  (short)(32768 * -0.007448193692118567),
  (short)(32768 * -0.007940501940620482),
  (short)(32768 * -0.007570802072162988),
  (short)(32768 * -0.006296120449841751),
  (short)(32768 * -0.004371955618154949),
  (short)(32768 * -0.002391875073164555),
  (short)(32768 * -0.001236984700413469),
  (short)(32768 * -0.001922560128827416),
  (short)(32768 * -0.005356720327533458),
  (short)(32768 * -0.012055656297010635),
  (short)(32768 * -0.021882952959947619),
  (short)(32768 * -0.033888748300090733),
  (short)(32768 * -0.046312736456333638),
  (short)(32768 * -0.056783367797647665),
  (short)(32768 * -0.062699937453677912),
  (short)(32768 * -0.061735375084135742),
  (short)(32768 * -0.052358513976237808),
  (short)(32768 * -0.034257179158167443),
  (short)(32768 * -0.008554500746482946),
  (short)(32768 * 0.022249911747384360),
  (short)(32768 * 0.054622962942346594),
  (short)(32768 * 0.084568844473140448),
  (short)(32768 * 0.108316122839950818),
  (short)(32768 * 0.122979341462627859),
  (short)(32768 * 0.127056096658453188),
  (short)(32768 * 0.120656295327679283),
  (short)(32768 * 0.105420364259485699),
  (short)(32768 * 0.084152608145489444),
  (short)(32768 * 0.060257510644444748),
  (short)(32768 * 0.037105711921879434),
  (short)(32768 * 0.017464092086704748),
  (short)(32768 * 0.003100559033325746),
  (short)(32768 * -0.005373489802481697),
  (short)(32768 * -0.008418211280310166),
  (short)(32768 * -0.007286730644726664),
  (short)(32768 * -0.003638388931163832),
  (short)(32768 * 0.000858330713630433),
  (short)(32768 * 0.004847436504682235),
  (short)(32768 * 0.007476399317750315),
  (short)(32768 * 0.008440227567663121),
  (short)(32768 * 0.007898970420636600),
  (short)(32768 * 0.006314366257036837),
  (short)(32768 * 0.004261033495040515),
  (short)(32768 * 0.002261843500794377),
  (short)(32768 * 0.000680212977485724),
  (short)(32768 * -0.000319493110301691),
  (short)(32768 * -0.000751893569425181),
  (short)(32768 * -0.000752248417868501),
  (short)(32768 * -0.000505487955986662),
  (short)(32768 * -0.000184645628631330),
  (short)(32768 * 0.000087913008490067),
  (short)(32768 * 0.000253106348867209),
  (short)(32768 * 0.000306473486382603),
  (short)(32768 * 0.000277637042003169),
  (short)(32768 * 0.000207782317481292),
  (short)(32768 * 0.000132446796990356),
  (short)(32768 * 0.000072894261560354)
};

// Iowa Hills Hilbert transform filter coefficients
const short Hilbert_Minus_45_Coeffs[NO_HILBERT_COEFFS] = {
  (short)(32768 * -0.000072894261560345),
  (short)(32768 * -0.000132446796990344),
  (short)(32768 * -0.000207782317481281),
  (short)(32768 * -0.000277637042003168),
  (short)(32768 * -0.000306473486382623),
  (short)(32768 * -0.000253106348867259),
  (short)(32768 * -0.000087913008490148),
  (short)(32768 * 0.000184645628631233),
  (short)(32768 * 0.000505487955986583),
  (short)(32768 * 0.000752248417868491),
  (short)(32768 * 0.000751893569425298),
  (short)(32768 * 0.000319493110301983),
  (short)(32768 * -0.000680212977485245),
  (short)(32768 * -0.002261843500793748),
  (short)(32768 * -0.004261033495039842),
  (short)(32768 * -0.006314366257036280),
  (short)(32768 * -0.007898970420636345),
  (short)(32768 * -0.008440227567663343),
  (short)(32768 * -0.007476399317751102),
  (short)(32768 * -0.004847436504683540),
  (short)(32768 * -0.000858330713632029),
  (short)(32768 * 0.003638388931162351),
  (short)(32768 * 0.007286730644725833),
  (short)(32768 * 0.008418211280310565),
  (short)(32768 * 0.005373489802483816),
  (short)(32768 * -0.003100559033321630),
  (short)(32768 * -0.017464092086698697),
  (short)(32768 * -0.037105711921871905),
  (short)(32768 * -0.060257510644436532),
  (short)(32768 * -0.084152608145481672),
  (short)(32768 * -0.105420364259479538),
  (short)(32768 * -0.120656295327675800),
  (short)(32768 * -0.127056096658453216),
  (short)(32768 * -0.122979341462631633),
  (short)(32768 * -0.108316122839958146),
  (short)(32768 * -0.084568844473150454),
  (short)(32768 * -0.054622962942358168),
  (short)(32768 * -0.022249911747396132),
  (short)(32768 * 0.008554500746472333),
  (short)(32768 * 0.034257179158159054),
  (short)(32768 * 0.052358513976232306),
  (short)(32768 * 0.061735375084133286),
  (short)(32768 * 0.062699937453678217),
  (short)(32768 * 0.056783367797650072),
  (short)(32768 * 0.046312736456337288),
  (short)(32768 * 0.033888748300094730),
  (short)(32768 * 0.021882952959951244),
  (short)(32768 * 0.012055656297013388),
  (short)(32768 * 0.005356720327535105),
  (short)(32768 * 0.001922560128828006),
  (short)(32768 * 0.001236984700413229),
  (short)(32768 * 0.002391875073163812),
  (short)(32768 * 0.004371955618154038),
  (short)(32768 * 0.006296120449840938),
  (short)(32768 * 0.007570802072162439),
  (short)(32768 * 0.007940501940620253),
  (short)(32768 * 0.007448193692118624),
  (short)(32768 * 0.006337182914262643),
  (short)(32768 * 0.004932965382553323),
  (short)(32768 * 0.003539247773172483),
  (short)(32768 * 0.002370114347025498),
  (short)(32768 * 0.001525299390682370),
  (short)(32768 * 0.001002372095321316),
  (short)(32768 * 0.000731530748682004),
  (short)(32768 * 0.000616670267768521),
  (short)(32768 * 0.000569479602046963),
  (short)(32768 * 0.000529324432676881),
  (short)(32768 * 0.000468041804899765),
  (short)(32768 * 0.000383511439791304),
  (short)(32768 * 0.000287988910943362)
};


// Instantiate the Objects
LiquidCrystal_I2C lcd(0x3F, 16, 2);       // Name for the LCD. Set the LCD address to either 0x27 or 0x3F for a 16 chars and 2 line display
Si5351 si5351;                            // Name for the Si5351 DDS
AudioControlSGTL5000    audioShield;      // Name for the Teensy audio CODEC on the audio shield

// Audio shield
AudioInputI2S           audioInput;                                           // Name for the input to the audio shield (either line-in or mic)
AudioOutputI2S          audioOutput;                                          // Name for the output of the audio shield (either headphones or line-out)
// Transmitter
AudioFilterFIR          TX_Hilbert_Plus_45;                                   // Name for the TX +45 Hilbert transform
AudioFilterFIR          TX_Hilbert_Minus_45;                                  // Name for the TX +45 Hilbert transform
AudioMixer4             TX_I_Sideband_Switch;                                 // Name for the sideband switching summer for the I channel

// Audio connections
AudioConnection         patchCord50(audioInput, 0, TX_Hilbert_Plus_45, 0);              // Mic audio to Hilbert transform +45
AudioConnection         patchCord55(audioInput, 0, TX_Hilbert_Minus_45, 0);             // Mic audio to  Hilbert transform -45
AudioConnection         patchCord60(TX_Hilbert_Plus_45, 0, TX_I_Sideband_Switch, 0);    // Hilbert transform +45 to receiver summer
AudioConnection         patchCord65(TX_I_Sideband_Switch, 0, audioOutput, 0);           // Output to the NE612
AudioConnection         patchCord70(TX_Hilbert_Minus_45, 0, audioOutput, 1);            // Output to the NE612


void setup()
{
  // Setup input switches
  pinMode(rotAPin, INPUT);
  pinMode(rotBPin, INPUT);
  pinMode(pushPin, INPUT);
  digitalWrite(rotAPin, HIGH);
  digitalWrite(rotBPin, HIGH);
  digitalWrite(pushPin, HIGH);

  // Setup interrupt pins
  attachInterrupt(digitalPinToInterrupt(rotAPin), ISRrotAChange, CHANGE);
  attachInterrupt(digitalPinToInterrupt(rotBPin), ISRrotBChange, CHANGE);

  // Setup the lcd
  lcd.begin();
  lcd.backlight();

  // Setup the DDS
  si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0);
  si5351.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
  si5351.drive_strength(SI5351_CLK0, SI5351_DRIVE_8MA);
  si5351.set_freq((freq * 100ULL), SI5351_PLL_FIXED, SI5351_CLK0);

  // Setup the audio shield
  AudioNoInterrupts();
  AudioMemory(16);
  audioShield.enable();
  AudioInterrupts();

  // Setup transceiver mode
  Turn_On_Transmitter();
  UpdateDisplay();
}

void loop()
{
  if (freq != oldfreq)                // Check to see if the frequency has changed. If so, update everything.
  {
    UpdateDisplay();
    SendFrequency();
    oldfreq = freq;
  }

  if (digitalRead(pushPin) == LOW)    // Update cursor, but also stop it from flickering
  {
    delay(10);
    while (digitalRead(pushPin) == LOW)
    {
      if (updatedisplay == 1)
      {
        UpdateDisplay();
        updatedisplay = 0;
      }
    }
    delay(50);
  }
}


void Turn_On_Transmitter()
{
  AudioNoInterrupts();
  audioShield.inputSelect(AUDIO_INPUT_MIC);
  audioShield.micGain(Mic_Gain);                                         
  audioShield.unmuteLineout();                                        // Output to the NE612s
  audioShield.lineOutLevel(Lineout_Gain);                         
  TX_Hilbert_Plus_45.begin(Hilbert_Plus_45_Coeffs, NO_HILBERT_COEFFS);
  TX_Hilbert_Minus_45.begin(Hilbert_Minus_45_Coeffs, NO_HILBERT_COEFFS);

  if (freq <= 9999999)          // LSB
  {
    TX_I_Sideband_Switch.gain(0, 1);
  }
  if (freq > 9999999)           // USB
  {
    TX_I_Sideband_Switch.gain(0, -1);
  }

  AudioInterrupts();
}


// Interrupt routines
void ISRrotAChange()
{
  if (digitalRead(rotAPin))
  {
    rotAval = 1;
    UpdateRot();
  }
  else
  {
    rotAval = 0;
    UpdateRot();
  }
}


void ISRrotBChange()
{
  if (digitalRead(rotBPin))
  {
    rotBval = 1;
    UpdateRot();
  }
  else
  {
    rotBval = 0;
    UpdateRot();
  }
}


void UpdateRot()
{
  switch (rotState)
  {

    case 0:                                         // Idle state, look for direction
      if (!rotBval)
        rotState = 1;                               // CW 1
      if (!rotAval)
        rotState = 11;                              // CCW 1
      break;

    case 1:                                         // CW, wait for A low while B is low
      if (!rotBval)
      {
        if (!rotAval)
        {
          // either increment radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1000000)
              radix = 100000;
            else if (radix == 100000)
              radix = 10000;
            else if (radix == 10000)
              radix = 1000;
            else if (radix == 1000)
              radix = 100;
            else if (radix == 100)
              radix = 10;
            else if (radix == 10)
              radix = 1;
            else
              radix = 1000000;
          }
          else
          {
            freq = (freq + radix);
            if (freq > bandEnd)
              freq = bandEnd;
          }
          rotState = 2;                             // CW 2
        }
      }
      else if (rotAval)
        rotState = 0;                               // It was just a glitch on B, go back to start
      break;

    case 2:                                         // CW, wait for B high
      if (rotBval)
        rotState = 3;                               // CW 3
      break;

    case 3:                                         // CW, wait for A high
      if (rotAval)
        rotState = 0;                               // back to idle (detent) state
      break;

    case 11:                                        // CCW, wait for B low while A is low
      if (!rotAval)
      {
        if (!rotBval)
        {
          // either decrement radixindex or freq
          if (digitalRead(pushPin) == LOW)
          {
            updatedisplay = 1;
            if (radix == 1)
              radix = 10;
            else if (radix == 10)
              radix = 100;
            else if (radix == 100)
              radix = 1000;
            else if (radix == 1000)
              radix = 10000;
            else if (radix == 10000)
              radix = 100000;
            else if (radix == 100000)
              radix = 1000000;
            else
              radix = 1;
          }
          else
          {
            freq = (freq - radix);
            if (freq < bandStart)
              freq = bandStart;
          }
          rotState = 12;                            // CCW 2
        }
      }
      else if (rotBval)
        rotState = 0;                               // It was just a glitch on A, go back to start
      break;

    case 12:                                        // CCW, wait for A high
      if (rotAval)
        rotState = 13;                              // CCW 3
      break;

    case 13:                                        // CCW, wait for B high
      if (rotBval)
        rotState = 0;                               // back to idle (detent) state
      break;
  }
}


void UpdateDisplay()
{
  lcd.cursor();                                     // Turn on the cursor
  lcd.setCursor(0, 0);
  lcd.print("        ");
  lcd.setCursor(0, 0);
  lcd.print(freq);
  lcd.setCursor(10, 0);
  lcd.print("ZL2CTM");

  lcd.setCursor(0, 1);
  lcd.print("        ");
  lcd.setCursor(0, 1);

  if (freq > 9999999)
  {
    if (radix == 1)
      lcd.setCursor(7, 0);
    if (radix == 10)
      lcd.setCursor(6, 0);
    if (radix == 100)
      lcd.setCursor(5, 0);
    if (radix == 1000)
      lcd.setCursor(4, 0);
    if (radix == 10000)
      lcd.setCursor(3, 0);
    if (radix == 100000)
      lcd.setCursor(2, 0);
    if (radix == 1000000)
      lcd.setCursor(1, 0);

  }
  if (freq <= 9999999)
  {
    if (radix == 1)
      lcd.setCursor(6, 0);
    if (radix == 10)
      lcd.setCursor(5, 0);
    if (radix == 100)
      lcd.setCursor(4, 0);
    if (radix == 1000)
      lcd.setCursor(3, 0);
    if (radix == 10000)
      lcd.setCursor(2, 0);
    if (radix == 100000)
      lcd.setCursor(1, 0);
    if (radix == 1000000)
      lcd.setCursor(0, 0);
  }
}


void SendFrequency()
{
  si5351.set_freq((freq * 4) * 100ULL, SI5351_PLL_FIXED, SI5351_CLK0);

}

****************************************************************