Fldigi Users Manual  4.2.00
PSK Configuration
Modems PSK General


You should set the acquisition search range for waterfall left click action. As you adjust this control you will see the red mode width change on the waterfall scale. You can also adjust this value by pointing the mouse to the waterfall. Hold down the Control key and rotate the mouse wheel. The search routine which finds the PSK signal operates on a s/n threshold detector as well as recognizing the PSK phase modulation. You can adjust the acquisition signal to ratio threshold for the search routine.

The PSK decoder estimates the signal to noise ratio, S/N, and the intermodulation distortion, IMD, of the received signal. This measurement is valid during periods when the other station is transmitting the idle signal. The estimates are displayed on the status bar. You can control how these values are displayed; clear or dim after NN seconds. Setting the seconds to 0 disables the clear/dim action.

Fldigi has a multi channel browser than can display simultaneous reception of up to 30 PSK signals. The browser is described here:

8psk (8 phase states) does not use AFC for signal acquistion or tracking. RsID or operator adjustment of tracking point is necessary to align the decoder with the received signal. This mode includes the optional use of a pilot tone. The level of the pilot tone can be set relative to the total signal power.

This table shows the amount of transmit power used by the pilot tone

dB -20 -26 -29 -32 -36 -40
Pwr Lvl 10% 5% 3.5% 2.5% 1.6% 1.0%


Signal Browser


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