Rosendahl bonsaiDRIVE - Manual (Page 20)

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MENU 028 2TRK INPUT SENSITIVITY
The sensitivity of the analog 2 track inputs can be adjusted in 3 dB
steps from -6 dBU up to +9 dBU as digital full scale level.
MENU 029 2TRK OUTPUT LEVEL
The full scale level of the analog 2 track outputs can be set in 3 dB
steps from -6 dBU up to + 9 dBU.
MENU 030 TIME CODE CHASE MODE
The time code chase mode is a function that synchronises the
bonsaidrive to an external time code. The machine chases (runs
after) and locks to the external time code. The bonsaidrive requires a
time code signal in the correct time code format, i.e. 25 FPS for PAL
or 29.97 FPS DF/ND for NTSC video formats (see menu 070 VIDEO
STANDARD).
The time code can either be LTC (sometimes describes as SMPTE)
or MTC, Midi Time Code format, and can be selected with menu 031
TIME CODE INPUT.
There are 6 different chase settings:
(1) DISABLE
No synchronisation to external time code.
(2) VARISPEED
In this setting the audio and video follows the speed of the input time
code. The nearest video frame to the current time code position is
shown and the audio channels are output in varispeed with so called
linear interpolation (14 bit). The audio quality is not as good as in the
normal play function which has sample synchronous audio playback.
The frequency of the word clock signal at output C2 and the
digital Audio output C11 do not follow the chase time code
exactly and may not be synchronous with it.
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The picture and audio signals however are output synchronous to the
chase time code.
The state of the varispeed is shown by the lighting up of either the [+]
or [–] keys. [+] means that the play speed is over the nominal value
and [–] under the nominal value.
The varispeed chase mode should be used if it is not possible to
synchronise the master and slave machines to a common house
sync, or if using the bonsaidrive just as a picture player without audio.
(3) GENLOCKED
If the feed time code is locked to the video output of the bonsaidrive
or to a house sync one should use the setting GENLOCKED.
In this mode at the start of play, the first video frames are
synchronised as in VARISPEED above, but after the correct frame
position and video phase have been reached the play speed
switches over automatically to nominal and is not regulated any
more. This status is easily recognised as only the play key lights up
in forward mode.
When using a synchronous time code source, sync is guaranteed by
the fact that both time code and the bonsaidrive are synchronised by
the same sync source.
In normal playback mode the audio signals are not interpolated and
are played back with full 24 bit resolution.
Should the time code and picture not be exactly synchronised, then
- when the error reaches 1 frame - a correction is made as in
varispeed until the error is cancelled. Then genlock mode is switched
in again.
Genlocked chase mode is mostly used in the synchronisation of
professional video machines or when using several bonsaidrives
coupled together.