Sonifex Net-Log, Руководство пользователя, Страница: 54 / 66

11. The Administrator
User Name & Password
To change a user name or password, select the user
whose details you wish to change and type in a new name
or password ( Figure 11.5 ).
Note that all the changes made will only take effect when
the “Update” button is pressed. If “Abort” is pressed then
the changes are lost.
The Onboard Clock
The Net-Log uses an accurate onboard real time clock
(RTC) to record the start & stop times of cuts and to start
& stop record programs. This time is stored on the Net-
Log in UTC format which is identical to Greenwich Mean
Time and is unaffected by any summer or daylight saving
time schemes.
The accuracy of the RTC is +/– 1.53 minutes per month.
This equates to about 3 seconds per day. During long or
continuous recordings, an error can develop between the
actual time a piece of audio is recorded, and the time used
from the RTC to reference the cut. In a worst case
scenario, when the RTC is running slightly slow with
respect to real time, the audio at the end of a long
recording could be unavailable. This is because the time
stamp taken from the RTC for the end of the cut would be
earlier than the actual time the cut ended. To overcome
this, the Net-Log firmware determines whether the RTC
derived time for the end of a recording differs from the
time the Net-Log calculates the cut should end at. This
calculation is made using the start time and length of the
recording. Future play or archive accesses to this cut will
then use this error figure to bias the search calculation so
that the whole cut is accessible.
If the RTC has drifted, then the start time of any new cuts
will not be a true reflection of the actual time the
recording was started. If the start time for a recording is
inaccurate, the time displayed when playing the recording
and when searching within it will also be inaccurate. Also,
if program record mode is used, the automated record
starts/stops will not happen at exactly the right time. It is
important therefore, to regularly update the RTC if
accurate audio to time synchronisation is required.
Updating The Onboard Clock
The onboard clock can be updated at any time. If an
update occurs whilst a channel is recording, and the
difference between the current RTC and the time update is
greater than two seconds, the recording will stop prior to
the clock update. Once the clock has been updated, a new
recording will automatically begin. This is done to reduce
the error correction required when searching for audio. It
also happens so quickly that you will not lose any audio.
However there will be a time difference between the two
recordings.
There are two options for RTC clock updates. The first is to
update Net-Log with the time currently set on the
connected PC. This is an administrator only function and it
is not automatic. The second option is to automatically
synchronise the onboard clock to a specific PC using the
Mentor software. It is advisable to have the clock on the
PC running the Mentor server accurately maintained from
an external source. The Mentor software will then
distribute the time information to multiple Net-Logs every
30 minutes.
Figure 11.5 Select or Edit User Name & Password
Sonifex Net-Log-Win User Handbook
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