Ricoh MP C307 Field Service Manual page 1173

the end of communication
0: Disabled
1: Enabled
2- Not used
3
4 Sidaa manual calibration setting
0: Off
1: On
5- Not used
7
at the end of fax communication, change this bit to "1".
Do not change these settings.
1: manually calibrates for communication with a line whose
current change occurs such as an optical fiber line.
Do not change the settings.
4.Service Tables
91