Ricoh Type M12, Field Service Manual

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2-3
PSTN cable equalizer
(rx mode: Internal) 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.
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.
• This setting is not effective in V.34
communications.
Bit 3 Bit 2 Setting
0 0 None
0 1 Low
1 0 Medium
1 1 High
4
PSTN cable equalizer
(V.8/V.17 rx mode: External)
0: Disabled
1: Enabled
Keep this bit at "1".
5 Not used Do not change the settings.
6
Parameter selection for dial tone
detection
0: Normal parameter
1: Specific parameter
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.
7 Not used Do not change the settings.
G3 Switch 08 - Not used (do not change the settings)
G3 Switch 09 - Not used (do not change the settings)
G3 Switch 0A (SP No. 1-105-011)
No Function Comments
Bit Switches - 4
139