PskScope Operation


Select the operating mode, either Psk-31 or Psk-63 from the pull down menu:



This is also the menu that provides access to the simulation mode.

Select the sampling interval (.5, 1.0 or 2.0 seconds).  You may find that you want the shortest interval between samples when using automatic level conrol.  The default of 1 second should be satisfactory.  If your computer is ancient and slow, try the 2 second interval



Select the Signal View that you want to use.  Either the Signal or the Spectrum view will be most useful during normal operations:

The 4 views are selected by the notebook tabs:

Signal View


On Air Psk-31 Transmitting Characters

Spectrum View


On Air Psk-31 Transmitting Characters

A/D Data View


On Air Psk-31 - Raw data (normalized to 8 bits)

Antenna Data View


On Air Psk-31 Filtered Data

The Spectrum display is a derived rf display.  This has the appearance of the transmitted rf spectrum.  A good PSK signal looks like a single tone DSB signal on the waterfall.  In fact, the idle signal is for all purposes is the same as a two-tone test signal.  The center line of the Spectrum Display is the effective suppressed carrier of the PSK signal.  Sidebands appear on both sides of the carrier.  A single sideband with perhaps just a little of the 3rd harmonic is normal for most modern transceivers unless you are overdriving the audio.  Then you will see multiple sidebands including the 3rd, 5th  and 7th.  Because of the signal processing used in the program you will not see any even harmonics on the display.  Even harmonics are almost never introduced into the actual transmitted signal.

Note the discontinuity in the signal view window.  This is caused by the asynchronous sampling of the transmitted signal.  The data has been rotated and normalized prior to being displayed in this view.  The peak value of the displayed waveform will not change with power output!  But the shape of the signal will change if you overdrive the transmitter.


Previous
Contents
Next