/*
 * Program: Global Communicator II - scanner signals converter
 * Programmer: Robert John Morton UK-YE572246C
 * Date:  Tue 22 Sep 2020

From the directory in which 15.c resides: 
to compile: gcc 20.c -o 20 */

#include <stdio.h>   // input output to/from the console and keyboard
#include <stdlib.h>  // standard functions for the 'C' language

int S[301] = {  // signal strength per pseudochannel
    2, 30, 50, 30, 20, 40, 20, 35, 50, 35,
   40, 25, 20, 30, 20, 30, 45, 30, 43, 50,
   32, 38, 28, 31, 43, 31, 43, 50, 41, 37,
   74, 71,100, 71, 67, 95, 67, 28, 39, 36,
   49, 35, 24, 21, 30, 43, 30, 21, 26, 38,
   52, 38, 26, 24, 34, 48, 34, 24,  2, 30,
   35, 50, 35, 25, 22, 30, 43, 30, 22, 24,
   27, 19, 39, 55, 78,110, 78, 55, 39, 71,
   62, 15 };

void main() {
  FILE *HS = fopen("scope.dat","rb+");  // open the output file for writing
  fseek(HS,14000,SEEK_SET);              // seek start byte for Top Band
  int i, c;

/* For the CW part of the band from 14000 to 14070 kHz
   there are 35 'channels' of 2 kHz each. The 1st 1kHz
   slot is noise and the 2nd 1kHz slot is a CW signal. */

  for(i = 0; i < 35; i++) {  // for each CW channel
    fputc(3,HS);     // put the inter-channel noise level
    fputc(S[i],HS);  // put the peak-held signal strength
  }
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level

/* For the USB part of the band from 14070 to 14100 kHz
   there are 7 channels of 4 kHz each. The 1st 1kHz
   slot is noise and the following 3 contain 3 1kHz
   sideband signal slots. */

  for(i = 35; i < 42; i++) {  // for each LSB channel
    int c = S[i];        // get the required sample
    fputc(3,HS);         // put the inter-channel noise level
    fputc(c * 0.82,HS);  // peak-held outer sideband signal strength
    fputc(c * 0.95,HS);  // peak-held middle sideband signal strength
    fputc(c,HS);         // peak-held inner signal strength
  }
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level

/* For the AM part of the band from 7045 to 7099.9 kHz
   there are 12 channels of 8 kHz each. The 1st 1kHz
   slot is noise and the following 7 contain 6 1kHz
   sideband slots + a central carrier signal slot. */

  for(i = 42; i < 82; i++) {  // for each AM channel
    int c = S[i];        // get the required sample
    fputc(3,HS);         // put the inter-channel noise level
    fputc(c * 0.82,HS);  // peak-held middle sideband signal strength
    fputc(c * 0.95,HS);  // peak-held inner sideband signal strength
    fputc(c,HS);         // peak-held full signal strength
    fputc(c * 0.95,HS);  // peak-held inner sideband signal strength
    fputc(c * 0.82,HS);  // peak-held middle sideband signal strength
  }
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fputc(3,HS);         // put the inter-channel noise level
  fclose(HS);  // close the output file
}