NexLog Recorder User Manual v2.2.0
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VoIP, VOX detect mode triggers off the presence or absence of RTP traffic, not
the actual levels.
VOX Hold:
If Detect is set to VOX , this sets the number of seconds the channel
will continue recording after the signal drops and remains below the threshold.
The factory default is 8 seconds.
Setting this for too long a value will record long periods of silence at the end of
transmissions; too short a value may break a single call into apparent multiple
call records at pauses on the conversation.
TRV Threshold:
This sets the DC voltage at which a phone line is assumed to be
in the off-hook state and eligible for recording. On a normal, clean telephone
line, this does not have to be set too finely. On-hook voltages are typically 40-55
volts, off-hook under 10 volts. The factory default of 28 volts will probably be
suitable.
Noisy telephone lines, lines at a great distance from the central office, and lines
that are recorded at one location but answered at another can have unusual
voltage profiles and may require adjustment. This setting is only available on
Analog boards.
TRV Hold:
If Detect is set to TRV, this sets the number of seconds the call will
continue to be recorded after the telephone goes on-hook. The factory default is
5 seconds. The on-hook state is then considered to define the end of the
conversation.
With a line that has normal ringing voltage on it ( +/-105V at 20-30 Hz), TRV
will also respond to the ringing voltage. This means that, with a default of less
than four seconds, each ring will appear to be a separate call. By setting TRV
hold to five seconds or more, with a normal ringing cadence only one call will be
logged from the beginning of the ring to completion of the conversation.
If you have set a channel to TRV, a special (non-programmable) feature will
detect and flag a disconnected line if the tip/ring voltage stays below 3 volts for
1 minute. If this happens, it generates a severity 2 (warning) alert indicating
signal loss
(Alert #9016). When the voltage equals or exceeds 3 volts, it
generates the corresponding “Resolved” alert for Alert #9016 to indicate the
signal is restored. TRV Hold setting is only available on Analog boards.
Input Gain:
Gain (or attenuation) in dB of the input channel - used to set
recording level on analog boards.
Input Level:
Real-time display of signal input level - useful for setting channel
gain. This is not an editable item. This information is very useful for diagnosing
recording problems, such as one call being broken up into multiple calls. Note
that depending on the detect type this can either be TRVolt readings or VOX
readings. Input level is available for Analog boards.
TRV Level:
This non-editable item shows you the real-time minimum, maximum,
and current value of the DC voltage at the channel input. The current value will
