Ricoh M160 Service Manual page 751

No Function
PSTN cable equalizer
(V.8/V.17 rx mode: External)
4
0: Disabled
1: Enabled
5 Not used
Parameter selection for dial tone
detection
6
0: Normal parameter
1: Specific parameter
G3 Switch 08 - Not used (Do not change the factory settings.)
G3 Switch 09 - Not used (Do not change the factory settings.)
M160/M161 Fax Option
G3 Switch 07 (SP No. 1-105-008)
Modem rate fallback occurs frequently.

Keep this bit at "1".
Do not change this setting.
0: This uses the fixed table in the ROM
for dial tone detection.
1: This uses the specific parameter
adjusted with SRAM (69ECBEH -
69ECDEH). Select this if the dial tone
cannot be detected when the "Normal
parameter: 0" is selected.
95
Comments
This setting is not effective in
V.34 communications.
Bit Switches - 4
SM