added modulo test for c mode

demo.sh

@@ -22,13 +22,13 @@ else
     echo $y
     echo $(($y % 4))
     
-      if [ $(($y % 4)) = "0" ]; then
+      if [ $(($y % 4)) = 0 ]; then
    	   echo "Mode is continuous AFSK"
     	   /home/pi/CubeSatSim/radioafsk afsk
-      elif [ "$1" = "b" ]; then
+      elif [ $(($y % 4)) = 1 ]; then
    	   echo "Mode is continuous BPSK"  
     	   /home/pi/CubeSatSim/radioafsk bpsk
-      elif [ "$1" = "s" ]; then
+      elif [ $(($y % 4)) = 2 ]; then
    	   echo "Mode is continuous SSTV"  
     	   while true; do sleep 5; done
       else