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Chapter 3 Features and Functions
Triggering
3
Trigger Input Signal
This rear-panel connector is used in the following modes:
• Triggered Sweep Mode: To select the external source, press the
Trigger Setup softkey and then select the Source Ext softkey or
execute the TRIG:SOUR EXT command from the remote interface
(sweep must be enabled). When the rising or falling edge (you specify
which edge) of a TTL pulse is received on the Ext Trig connector,
the waveform generator outputs a single sweep.
•
Externally-Modulated FSK Mode
: To enable the externally-modulated
mode, press the Source softkey from the front-panel or execute the
FSK:SOUR EXT command from the remote interface (FSK must be
enabled). When a logic low level is present, the carrier frequency is
output. When a logic high level is present, the hop frequency is
output. The maximum external FSK rate is 100 kHz.
• Triggered Burst Mode: To select the external source, press the
Trigger Setup softkey and then select the Source Ext softkey or
execute the TRIG:SOUR EXT command from the remote interface
(burst must be enabled). The waveform generator outputs a waveform
with a specified number of cycles (burst count) each time a trigger is
received from the specified trigger source.
• External Gated Burst Mode: To enable the gated mode, press the
Gated softkey or execute BURS:MODE GAT from the remote interface
with burst enabled. When the external gate signal is true, the
waveform generator outputs a continuous waveform. When the
external gate signal goes false, the current waveform cycle is
completed and then the waveform generator stops while remaining
at
the voltage level corresponding to the starting burst phase. For noise
,
the output stops immediately when the gate signal goes false.