Sangean ATS-606A - Manual (Page 45)

3.After the whole scanning is completed, a beep
tone will be heard. Display will show M [1] and
the frequency which is the strongest signal in
your area will be heard.
4.If no stations are found, display will show '----'
for 2 seconds and return to last tuning
frequency.
44
FW
M 1 2 3 4 5 6 7 8 9
FW
9