change in the behaviour of AFC "search direction" in the decoder ?

In the demod the Automatic Frequency Control looks for the centre frequency of the signal by "panning" down in frequency. Once it finds it it goes up & down a little to stay with it, as any good AFC should :)

If anything interrupts the signal and it loses the "lock", then it starts to "hunt down in audio frequency again until it reaches the "low Freq:" which is set as a parameter, and then it stays there.

The user can click back above the frequency and it will again hunt downwards to find lock again.

I propose that it would be good functionality in the case of a loss of signal to either: a) When hitting the low freq: then start to hunt up in frequency again or, b) when hitting the low freq: then jump up to the hi freq: parameter and start to hunt back down again.

This would make unattended operation much, much more reliable when the signals are weak (as with mine) and heavy rain or some other event blocks the signal for a short time. It is disappointing to go away and come back and find the line red and sitting at the bottom of the frequency range... Even more so when you realise it happened 5 minutes after you walked away :)

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