4-10
IM 704420-01E
Explanation
Arming refers to the cue used to start the measurement. As opposed to a trigger, which
refers to the cue used to measure the pulse width or time difference of each pulse,
arming refers to the starting point of the measurement of a set of pulse widths or time
differences used to derive the jitter.
Selecting auto arming (internal arming)
If you turn OFF both the
and
indicators, auto arming is activated. The internal
signal of the TA120E is the arming source. Arming is the cue used to start the first
measurement (the first trigger).
Setting external arming
Arming is activated when an external signal (arming source) is applied to the external
arming input connector.
• Selecting the slope
•
: Arming is activated on the rising slope of the external arming signal.
•
: Arming is activated on the falling slope of the external arming signal.
• Setting the arming delay
When using external arming, set the delay time of arming in the range shown
below. When the value can be specified, the [SET] indicator lights and the delay
time is shown on the display.
• Range: 0.0 ms to 1000.0 ms
• Resolution: 0.1 ms
• External arming signal
Input the external arming signal to the connector indicated as “EXT ARM IN” on the
rear panel.
Item
Specifications
Input impedance
10 k
Ω
(typical value*)
Input coupling
DC
Input level
TTL level
Allowable input voltage range
–8 V to 13 V (DC+ACpeak)
Minimum input pulse width
30 ns
Setup time
0 ns (possible even when the external arming and data
signal are simultaneous)
*
The typical value is a representative or standard value. It is not a warranted value.
4.5 Setting the Arming
