Talbot Andrew wrote:
Has
anyone looked at what Signal to Noise is realistically viewable on a spectrogram
display ? Assuming bandwidth equal to FFT bin size, my few
tests suggest around 10dB but it would be nice to have a more authoritative
figure to calculate with. Obviously depends on colour palette
and number of colours on the display so after a couple of years of experience
with Spectrogram and now Argo, what has anyone found ?
Maybe those 10dB are a bit on the pessimistic side. Before writing
Spectran and Argo, I used the FFTDSP program by AF9Y, which has
an S/N indicator. I remember having seen with it traces of signals
whose S/N was reported being a couple of dBs.
Those of you who have calibrated signal sources could arrange a testing
fixture to give more accurate values.
73 Alberto I2PHD
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