The spectrometer samples one minute of the 20m band (14056 kHz ~ 14104 kHz) every 15 minutes. For example, 00:00~00:01, 00:15~00:16, 00:30~00:31, 00:45~00:46, 01:00~01:01, etc.

On the top of spectrometer page there are four controls; a drop down list containing a list of time stamps for the stored spectrograms, and three controls for reversing and forwarding the time, and advancing to the latest spectrogram.

The image just below the controls is a spectrogram containing one minute of spectrum. The color tones are between black and white, with intermediate values in blue, representing different power levels. The software automatically adjusts the color contrast level to match the highest detected power and the noise floor. The scale for the spectrogram is represented in seconds.

The central part of the image is frequency scale in kHz.

The lower part of the image is a cumulative spectrum where power levels for the same FFT bin on all FFTs are superimposed. The scale is represented in dB relative to the full scale of the soundcard ADC (dBFS).

The lower part of the page contains a horizontal scroll bar for scrolling the image.

73 de Edson