Spectrogram Windaq add-on employs a powerful FFT module. It visualizes the frequency domain of an analog waveform in real-time, with 3D color-scaled waterfall spectrogram

Features

• Multiple FFT sizes: 1024, 2048, 4096 and 8192 Please make sure you upgrade to the latest DATAQ ActiveX. WinDaq Activex had a glitch that affects certain configuration of the add-ons and it was fixed recently.
  • Due to Windaq's memory allocation approach, the following rule should be observed if you wish to use this add-on:
    • For FFT size of 1024, up to 58 channels can be enabled in Windaq
    • For FFT size of 2048, up to 29 channels can be enabled in Windaq
    • For FFT size of 4096, up to 15 channels can be enabled in Windaq
    • For FFT size of 8192, up to 7 channels can be enabled in Windaq
  • DC component of the signal can be removed before FFT is performed
• True full ADC resolution . No more need for the Dynamic Amplifier option available in the first generation of Spectrogram
• Multiple Spectrograms can be enabled for different channels under Windaq
• Channel number is a 0-based index to Windaq's scanlist. For example, if Windaq has channel 3,4,6,7 enabled, one can enter 0 for channel 3, 1 for channel 4, 2 for channel 6 and 3 for channel 7. Must read: The mystery of channel index!
• Regarding the update interval
  • The update interval is controlled by Windows's Timer, which is
    • 15.6ms minimum by default under Windows 7
    • 20ms minimum by default under Windows XP
  • The power of PC's CPU also determines if the minimum update interval is achievable or not
  • Actual (averaged) update interval will be displayed on the spectrogram is started
  • Actual (averaged) update interval will be used to calculated the elapsed time for the cross-hair
• For the Spectrum display on top
  • Single click on AutoSet button will adjust the scale to bring a weak signal into sight immediately
  • While acquiring spectrum, you may
    • use the left mouse button to drag the waveform up and down
    • double-click the left or right mouse button to change the scaling of the waveform. 
    • push down the right mouse button to enable a vertical cursor to exam to the waveform.
  • Once you stop the live frequency display, you may 
    • push down the left mouse button on the chart to enable a vertical cursor and drag it around to study the spectrum
    • push down the right mouse button on the chart to enable a cross hair and drag it around to study the spectrum
• For the Waterfall display on the bottom
  • The waterfall display follows the scaling and offset of the spectrum display on top
  • You may also click the left mouse button on the waterfall chart to enable a crosshair to show the frequency/elapsed time  
• The frame of Spectrogram II is sizable, and the two charts will adjust accordingly
• Intelligent Channel Select: Highlight/Select a channel in Windaq and fire up this Windaq add-on, and it will use the selected channel as its default channel