Locked Re: WSJT-X is not decoding but shows signals on waterfall

Martin G0HDB <marting0hdb@...>

On Wed, Mar 4, 2020 at 08:06 PM, Dave S wrote:
I've had the same problem.
Seems like the last time it happened, I tried lowering the RF Gain and it started decoding every sequence.
I wasn't getting high readings on the level meter at the time
If you're operating your receiver with the AGC turned off, as advised in the WSJT-X user documentation ("It is usually best to turn AGC off or reduce the RF gain control to minimize AGC action."), then you need to make absolutely certain that you're not suffering from overload somewhere along the receiver chain that's causing the audio output from the receiver to become distorted.  A quick listen to the audio should give you a good feel for the quality of the signal going into WSJT-X; any distortion will cause havoc with the signal processing and consequentially an absence of decodes. 

As per the above quote from the User Guide, if you've turned the AGC off then it's necessary either to bring in sufficient RF front-end attenuation and/or to turn the receiver's RF gain control down until the audio sounds clean on even the strongest signals; it might then be necessary to increase the audio output level from the receiver and/or to adjust the computer's 'recording' audio level control to enable the recommended reading of 30dB on the WSJT-X 'thermometer' to be achieved when receiving only band noise.

Martin G0HDB

Join {main@WSJTX.groups.io to automatically receive all group messages.