Model 4040DDS– Operating Manual
12
3. Use good quality attenuators if it is necessary to reduce waveform amplitudes applied to sensitive circuits.
4. Use termination or impedance-matching devices to avoid reflections.
5. Ensure that attenuators and terminations have adequate power handling capabilities.
If there is a DC voltage across the output load, use a coupling capacitor in series with the load. The time constant of
the coupling capacitor and load must be long enough to maintain pulse flatness.
Impedance Matching
If the waveform generator is driving a high impedance, such as the 1 Mohm input impedance (paralleled by a stated
capacitance) of an oscilloscope vertical input, connect the transmission line to a 50 ohms attenuator, a 50 ohms
termination and to the oscilloscope input. The attenuator isolates the input capacitance of the device and terminates
the waveform generator properly.
3.6 FUNCTION Keys
These keys select the main menus for displaying and changing a parameter, function or mode.
3.6.1 WAVEFORM Keys
The keys select the waveform output and displays the waveform parameters (frequency, amplitude or offset).
The SINE, RAMP and SQUARE pushbuttons select the output waveform. A build-in LED indicates the waveform
selected.
Sine Menu
FREQ button - (Frequency) Selects and displays the frequency. Change the frequency setting using the cursor
keys and the rotary knob. This pushbutton returns to Frequency display from any other menu
displayed.
AMPL Knob - Changes the waveform Amplitude.
OFST button -Selects the Offset parameter. Change the offset by using the cursor keys and Amplitude/Offset
rotary knob. If a certain setting cannot be produced, the waveform generator will display a
“Setting Conflict” message.
Amplitude and Offset Interaction:
Amplitude and offset settings interact and are bound by hardware restrictions. In order to obtain the desired
waveform the following amplitude and offset hardware limitations must be considered:
Offset Menu
To Next Page
Loading...