Service Manual - AMS Neve

MACHINE PARAMETERS
SynchroNet ES/2 Service Manual
MAXSTP $100f/10
The required servo value is calculated 5 times each frame of timecode. This parameter sets the
maximum amount by which the servo may be adjusted each time, thus limiting the slew rate of the
servo output. This is important if the machine speed is to track the servo output accurately.
This parameter is not used on serially controlled machines.
VIDEO $1011
Video machines are not held in external speed control but are pulled into lock and then released to
lock to external video syncs. If this parameter is zero then the machine is always held in external
speed control to hold lock. If it is non zero then the machine is pulled into lock, held there for VIDEO
servo accesses and then the servo is released.
See REPRATE (1015) for an explanation of servo accesses.
VIDJMP $1012
When a video machine is released from external speed control to lock to external video syncs the
tape may jump. In order to achieve a stable lock the ES/2 must pull the machine’s position to a point
that is the correct number of frames from lock and then release the servo. The machine should then
jump the required amount into lock.
Those machines that do not have a repeatable jump characteristic cannot be used with the ES/2
system as video slaves.
NOSVO $1013
This parameter should be set to a non zero value ($FF) if the machine cannot be controlled in
external speed mode. This parameter engages the use of Real Master mode in Eclipse or Remote
Master mode in Penta, if this mode is possible in the system.
NOWILD $1014
This parameter should be set to a non zero value ($FF) if the machine should be held in external
speed control mode for ALL play conditions.
REPRATE $1015
display : REPRAT
It was stated above that the servo output is updated 5 times per frame. Some machines cannot
keep up with this rate of update so it may be slowed down by reprate. If this parameter is set to be
non zero then each servo access will be followed by REPRATE accesses being missed out, e.g. if
REPRATE is 4 then the servo will be updated once per frame (do 1 miss out 4).
DFACTOR $1016
display : DFACTO
This parameter is set for the machines deceleration characteristics when in external speed control.
The larger this number is then the earlier the servo will decelerate the machine as it approaches
lock. This parameter should be set as small as possible consistent with minimum overshoot, it is
only for the case where the machine is lagging and therefore decelerating into lock (see below).
DFLEAD $1017
It has been found that the characteristics of machines differ under deceleration and acceleration so
this parameter provides the same function as DFACTOR but for when the machine is leading and
needs to accelerate up to lock.
3:6 Issue 1