S E T U P F O R M
C H A P T E R 4
Signal Generator
Figure 131: AF Signal Generator
This Signal Generator sends an AF signal to either the input or output of either the receiver or the
transmitter DSP. It is used to test the PowerSDR.
Mode:
Select the type of signal to generate. “Soundcard” means the Signal Generator is turned
off and FLEX-5000 hardware can be used.
Note:
When finished with the Signal Generator, do not forget to place the
Signal Generator back to “Soundcard”.
Scale:
A scaling factor to adjust the level of the signal being generated. This is only available
when “Tone” is selected. Only values smaller than 1 are possible.
Input:
The generated signal is sent to the Input of the DSP, as if it were coming from the ADC
like your antenna signals would. The generated signal is therefore perceived as an IF signal by
PowerSDR.
For example, if your IF is set at the default 9kHz, then for the Receive Signal Generator a 0Hz
generated “Tone” would be displayed 9kHz below the VFO frequency on the Panadapter. As you
increase its frequency, upper and lower side band mixing products appear. If you have selected
USB mode on the Front Console you will only start to hear a tone when the frequency slider is
above 9kHz such that the tone's upper side band is within the audio passband. If you select the
Scope display, you will only see the signal when it is within the audio passband.
Output:
The generated signal is sent directly to the output, bypassing the DSP. The tone of the
Receive Signal Generator is available from the Line Out jack on the back panel for viewing on
an external scope, for example. The effect of the DSP can be observed by comparing the
Output signal to the Input signal.
RX2:
Check to send the generated signal to the second receiver RX2.
Frequency Slider:
Determines the frequency of the generated signal
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2003-2008 FlexRadio Systems
