User's Manual

Sybox 2 manual (AI-08.01)
Page 3 of 6
Page 3 of 6
Pre-Trigger signal “Attention”
This signal has two functions: It goes active (LOW) exact 80ms before the sweep recording will
start. This lets programs know in advance at what time the recording will start.
At the same time when the Sweep signal get active, the Attention signal starts to change its
level every 4ms until Sweep goes inactive.
The 4ms time interval between two consecutive Attention edges describes the interval for five
movement sample (five samples at 1250Hz  250Hz).
4. Signal properties
Twisted pair lines
The DB15 cable is connected to the Trans-Computer inside the carrier. It is a twisted pair
connection for transmitting high frequency signals over long distances.
Inside the Sybox there is a Max3096 (Maxim) receiver that converts the signals to TTL level for
the opto couplers input.
Galvanic separation
With the opto couplers there is no galvanic connection between the Articulograph AG501 and
other connected computer or systems. This is for electrical safety and prevents disturbances.
High timing precision
Fig. 4 and 5 show the input (magenta) and output (green) of one opto coupler.
Fig. 3: 2= Pin5 of 3096 3= Pin 3 of 6N137
Fig. 4: 4= Output - Pin 6 of 6N137
The most delay is caused by the opto coupler 6N137. This delay is constant
All in all the signals timing precision is better than 50ns.
Connection over a long distance
The Sybox 2 is connected to the Articulograph AG501 with a 3m cable.