Appendix A: Specifications

CSA8000B & TDS8000B User Manual A-9

Table A- 7: Ports (cont.)

Specifications Characteristics
Gated Trigger Input --
Enable-to-Acquire
Delay
(Option GT equipped
instruments only)
3 trigger cycles, where each cycle is defined as (holdoff time + trigger
latency). For example:
With holdoff set to its minimum 5 s setting, and a 2.500 GHz clock
signal applied to the External Direct Trigger input (a period of 400 ps),
the Enable-to-Acquire delay is approximated as 3 x (5 s + 0.0004 s)
= 15.0012 s.
The Enable-to-Acquire delay is the amount of time after the Gated
Trigger has been enabled (the level goes from TTL LOW to HIGH)
when the first valid sample is retained by the system as the beginning
of the waveform record length. When the Gated Trigger is enabled and
triggers begin to occur, the system will reject the first three samples to
avoid system recovery conditions. Once the first three points have been
discarded, then the next valid trigger cycle will be the first point of the
record section.
Gated Trigger Input --
Maximum Disable
Time
(Option GT equipped
instruments only)
The system checks the status of the gated Trigger approximately once
per holdoff and re-arm cycle. If the Gated Trigger is disabled
immediately after this system check, it will allow nominally a maximum
time of (holdoff + trigger period) to elapsed before the checking for the
status of the Gated Trigger input, recognizing the disable condition, and
halting any further sampling of the signal.
Internal clock trigger
out
Square wave out from 50 Ω.back termination synchronized to the
TDR internal clock drive signal. Refer to Trigger System -- Internal
Clock.
Typical performance into 50 Ωtermination:
--0.20 to +0.20 V low level
+0.90 to +1.10 V high level
n DC calibration
output
DC voltage from low impedance drive, programmable to 1 mV over
±1.25 V range maximum. Accuracy is 0.2 mV + 0.1% into 50 Ω.
DC calibration output,
typical
Typical Accuracy is 0.2 mV + 0.1% into 50 Ω.
External 10 MHz
reference input
±5 V maximum

Table A- 8: Data storage

Specifications Characteristics
Floppy disk drive 3.5 in floppy disk, 1.44 Mbyte, compatable with DOS 3.3, or later,
format for storing reference waveforms, image files, and instrument
setups.
Hard disk drive ca-
pacity ≥20 Gbytes