BNC 630 - Manual (Page 61)

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7.5 Function Generator Mode
Figure 7.5-1: Function Generator Mode display
1. Waveform
In this field select the desired function generator waveform. You may select from among the following:
0. Positive Ramp
1. Negative Ramp 2. Triangle 3. Random (noise)
4. Positive Exponential 5. Inverted Positive Exponential 6. Negative Exponential 7. Inverted Neg Exponential
8. Sinewave
Select the desired waveform directly using the number keys or use the arrow keys or wheel to scroll through the list.
2. Continuous/Triggered mode
In this field select whether the waveform is generated continuously or on a single event basis. If you select Continuous mode, then
the waveform is immediately restarted once the end of the waveform is reached. If you select a Triggered mode, then the waveform
is halted after the last point is reached, and the waveform is not restarted again until another trigger occurs. The trigger can come
from three sources:
1. Pressing the Trigger key
2. Applying a low-to-high transition on the Ext. Trig In connector
3. Sending an ASCII "T" to the RS232 port
The 630 will simultaneously accept a trigger from all of the above sources.
To set Continuous mode, press 1 . To set Triggered mode, press 0 . Pressing any arrow key or rotating the wheel will toggle the run
mode between Continuous and Triggered.
3. Repetition Frequency
In this field enter the frequency at which the function will be repeated. You may enter from 0 Hz (DC) to 2.000000 MHz in 1 Hz
steps. If a value of 0 Hz is entered, the function waveform clock is halted. A high going synchronization pulse is given on the SYNC
Out connector (front panel) at the start of the waveform.
In Triggered mode, the waveform is generated once per trigger event. The duration of each waveform will be 1/Repetition
Frequency.
Tip : Very low function frequencies (<< 1 Hz) can be generated by setting the Repetition Frequency to 1 Hz. (This fills the waveform
memory with 16,000 points of the desired function.) Then go to Arbitrary Waveform Mode and enter the Clock Frequency to obtain
the desired function rep rate. Repetition Rate = Clock Frequency / 16,000
4. Level
In this field enter the 50 ohm loaded output level, from 4 mVp-p to 10 Vp-p in 1 mV steps. Into an open circuit, the voltage swing
will be twice the specified peak-to-peak value.
Waveforms with very narrow peaks (i.e. exponential) may have signal energy above the cutoff of the output filter (10 MHz). The
resultant signal may have a distorted shape and reduced peak-to-peak output swing.
Offset
You can enter a DC offset voltage for the output waveform by pressing the Offset key. For more information on output
offsets refer to the 630 User’s Manual section 4.4.
Function Gen Wave: Triangle
Cont Rep Freq: 2,000,000.00 Hz 1,000 mV
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