BK Precision 4070A User Manual Rev.2.2
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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 Negative 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 RS-232 port
The 4070A 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 2.0MHz
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.
NOTE: 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 ? 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 4070A User’s Manual section 4.4.
Function Gen
Wave: Pos Ramp
Cont Rep Freq: 100,000 Hz 1,000 mV
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