If available, set the transceiver power level control for maximum power output. I recommend starting out with a dummy load, but an 'off hour' for a band might work just as well if you do not have a dummy load. Here is the way to set up your transceiver for a clean signal. But you absolutely cannot tolerate that with the digital modes. In fact, that is what an analog RF compressor does, overdrive and then subsequent filtering. A little overdrive on a voice channel can be tolerated to a degree. Every modern SSB transmitter uses some automatic level control ALC for preventing overdrive for SSB voice.

None will exceed this value, even the simultaneous multi-tone modes like Throb. The peak amplitude of this signal is the peak amplitude of every modem signal generated by fldigi. The 'TUNE' button generates a continuous single frequency audio signal at the exact frequency to which the waterfall cursor has been set. You can set up your computer / transceiver for good solid performance without excessive drive. There is absolutely no reason for a transceiver driven by fldigi to exhibit this type of performance. Too often you see an overdriven signals on the digital sub-bands multiple audio sidebands on PSK, splatter from overdriven MFSK and RTTY. The last step is usually needed to insure that the settings are not lost when the operating system is closed and restarted. The waterfall palette used is 'default.pal', and the received signal is about 20 dB above the noise floor.Īpply and save the changes. The three signal views should be similar to this with the level/range controls set to -20 and 70 respectively. Remember that changing the WF/FFT/SIG level and range controls DOES NOT effect the decoder signal path. You can then proceed to adjust the waterfall/fft appearance when you have the audio Rx level adjusted correctly. The colors can be set to suit the users' color vision. The default settings will be good for most users. The transition levels can be adjusted on the 'Signal Level' configuration panel.

RED - signals too high, danger of decode errors YELLOW - signals level high, but still OK The diamond indicator to the left of the fldigi AFC button will be colored as follows:

The peak signals do should not exceed the upper/lower gray lines on the display. Make sure that the input gain controls are not set too hot. Then set the transceiver to an active portion of the digital band 14.070 MHz for PSK or 14.074 MHz for JT type digital signals. Adjust the audio path gain transceiver audio, external audio codec gain, and operating system gain for a noise level that is about -50 dB on the VU meter. Set your transceiver to a portion of the band with no signals 14.065 MHz might suffice. If your sound card a/d (also referred to as codec) is functioning correctly there should be no signal offset and the signal will be centered vertically about the x-axis.

Setting up fldigi on window 7