25
side of the LCD. If the “MODE" key has been pressed, the word
"MODE" will change to "MODE (T)".
6.2 Single trigger
When in the signal trigger mode, every time the "
Trig
"
button is pressed the generator will output one SWEEP, FSK,
PSK, ASK or BURST waveform. The length of the waveform is
set by the time duration of “tw”, the parameter. The ”ts” time
duration is invalid in single trigger.
Note1
: when using FSK in the single trigger mode, the output
frequency will be continuous at the value the F2 frequency is set
to. When the "Trig" is pressed, the generator will output the F1
frequency value for the duration of the “tw” time then will return
to the continuous output at the f2 frequency..
Note 2
: When using PSK in the single trigger mode the
generator will output continuously the “fo” frequency value.
When the Trig button is pressed the “fo” phase will change to the
value that is set in “ph” and will continue for the duration set by
the “ts” value then return back to the original “fo’ phase value.
When in single trigger, the generator outputs a TTL level
pulse though the SYN output when the Trig button is pressed
which can be used to trigger an oscilloscope.
Single trigger mode requires that there is no signal input
through BNC; otherwise they can interfere which each other
6.3 External trigger
When the generator is in the single trigger mode the External
trigger input is also enabled. When the rising edge of the
external ttl pulse is applied to this input can trigger the waveform
at the rate of the external trigger signal as long as the frequency
of the trigger signal is longer than the modulation’s “ts” width
