Ricoh D072 Service Manual page 628

Cable equalizer
Bit 7: 0, Bit 6: 0, Bit 5: 0 = None
Bit 7: 0, Bit 6: 0, Bit 5: 1 = Low
5-7
Bit 7: 0, Bit 6: 1, Bit 5: 0 = Medium
Bit 7: 0, Bit 6: 1, Bit 5: 1 = High
Bit 7: 1, Bit 6: 1, Bit 5: 1 = Disabled
SM Appendix
Dedicated Transmission Parameters
Use a higher setting if there is
signal loss at higher frequencies
because of the length of wire
between the modem and the
telephone exchange when calling
the number stored in this
Quick/Speed Dial.
Also, try using the cable equalizer if
one or more of the following
symptoms occurs.
Communication error with error
codes such as 0-20, 0-23, etc.
Modem rate fallback occurs
frequently.
Do not use settings other
than listed on the left.
If the setting is "Disabled", the bit
switch setting is used.
7-89 D067/D068/D069/D072