[hpsdr] sampling

[Lyle Johnson]

> Say you sample 30 MHz at 60 MHz rate and you just happen to convert on the zero cross at 0 and 180 degrees. What information will you get? I would think you would need to sample at least 4 times to catch real information. Heck we sample audio at 192 khz these days so why ? That is at least 10 samples per highest audio frequency. Frank and other grasshoppers???

This is why you need either (a) dithering which you can remove or (b) 
sampling slightly higher than 2x.

73,

Lyle KK7P


 1177216588.0