fldigi waterfall examples

When I first started with digital modes fldigi didn't decode the way I expected it.

The problem was the radio output level was simply too high.
Digital modes are all about signal to noise ratios and not absolute signal levels

Screenshots on this page are intended to illustrate what signal level is required for fldigi to provide successful decoding.

This is a typical waterfall display on 14.070MHz. Take particular note of the background which has only a few background noise specs showing in yellow.
Adjust the radio output level and noise blanker until your 

typical waterfall
Typical Waterfall with PSK

 

The following image shows PSK signals which are too weak for reliable decoding:

PSK signal too weak to decode

Here is a PSK signal which should decode almost perfectly:

PSK signal with 100% decode