Canon FAX-B820 Service Manual page 31

#3 NUMERIC PARAM.
The relationship between the settings and the detection levels is as follows:
Parameter 23
0: -26 dBm 1: -30 dBm 2: -32 dBm 3: -35 dBm 4: -38 dBm
5: -41 dBm 6: -43 dBm 7: -45 dBm 8: -47 dBm 9: -51 dBm
Parameter 24
0: Not used 1: Not used 2: Not used 3: Not used 4: Not used
Parameter 26
0: -30 dBm 1:-34.5 dBm 2:-36.5 dBm 3: -40 dBm 4: -42 dBm
5: -46 dBm 6: -48 dBm 7: -50 dBm 8: -51 dBm 9: -54 dBm
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