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+The scanner should be able to scan about 20 frequencies per second, as it requires about 50ms to stabilize after re-tuning. 
+
+The scanner will stop into any frequency carrying a signal strong enough. You can adjust the signal power threshold with the SQUELCH.
+
+For better scanning precision, once a frequency with a powerful enough signal is found, the scanner will analyze it for some extra milliseconds, in order to confirm that the signal is still present (and not a spurious peak).
+
+# Big Numbers Frequency
+The big numbers display will show the frequency value currently being scanned, using the following color code criteria:
+
+* GREY scanning
+* YELLOW analyzing possible signal
+* GREEN found a strong enough signal
+
+
 # Frequencies to scan
 
 The application parses `FREQMAN\SCANNER.TXT`  by default. You can use the Frequency manager app (Tools -> **Freq managern**) to add more entries to that list.