Musicam FieldFone II, User Manual

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F I E L D F O N E I I U S E R S G U I D E
13 13
When this occurs, the
originating
FieldFone , FieldFone II or
StudioFone
will automatically redial the line if the auto redial option
has been set ‘ON’ (the default is ‘OFF’). You can also manually redial
the line, possibly using a lower bit rate if necessary. The maximum bit
rate can be changed with the keypad by using the command sequence:
<
Operation><Bit Rate><
baud rate
>
where <
baud rate
> = 33.6, 31.2. 28.8, ..., 14.4K
The maximum bit rate can be changed only when the FieldFone II is off
line. Although the FieldFone II will ‘fall back’ to 12.0 kb/s, you can
not initially establish a connection at bit rates lower than 14.4 kb/s.
Setting the rate threshold will also determine the bit rate of the
connection when the modem is going through the auto-baud sequence
when the connection is first established. Setting the rate threshold to HI
will allow fewer errors in the connection.
Under some circumstances, where the line condition is not constant, the
calling unit may establish a high rate connection that can not be
supported over time. If this occurs, the
FieldFone II
will automatically
re-negotiate the connection, causing a momentary muting of the audio.
You can also manually hang up and redial selecting a lower bit rate
before re-establishing communication.
Setting Loopback State
Five loopback states are available, and they are an invaluable
troubleshooting aid should you encounter problems. The system
loopbacks can be accessed by using the command sequence:
<Setup><Sys Loopback><
state
>
where <
state
> = Local Lb, Conv Lb, Modem
LB, Remote LB or None
In Converter Loopback , the loop-back is performed after the A/D
converter, before the encoder. This mode can be used to test the
functionality of the A/D and D/A
converters and for adjusting input and
output levels. When this mode is selected,
the FieldFone II display should look like
this:
In Local Loopback , the signal is looped through the encoder and
decoder, but not through the modem. This mode is used for testing the