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[linrad] Re: Volume control in filter window.

    Hello All,

    Finally after all the help, I have Linrad running as a single channel
    detector. The problem here was probably all along, the setting of the
    volume/level(?) control on the left side of the bandwidth window.

    When I loaded and started de software the very first time I saw signal
    in all three windows but no sound! I wrongly assumed all kinds of 
    problems basically around the back end of the sound card not getting
    signal to send to the output ( speaker ) Though the instructions mention
    this volume control later in the text, I overlooked this at the start
    or what have you.
    Also, the red bar is not visible when I start-up the software. 
    I am having trouble to understand exactly what this control is doing or
    what its function is and have not found anything about it.
    My guess is that it acts as a variable level switch to output
    sound. It sounds to be discreet and not continuous.
    With no signal and the bar all the way down the output is totally blocked
    no sound or noise is coming from the speaker. Have not been able to 
    check yet how the transition from no sound to sound is happening, most 
    likely as a function of the desired signal level and the volume control 
    setting or, one effecting the other. 
    It appears that around the 20 scale divisions point the sound channel is
    opening up and I can hear clean weak audio depending on the position of 
    the bfo signal though quite weak.
    Again with no signal going in, when the setting of this control is 
    increased however, the audio output is increasing up to the point that it
    starts to ring or even start to oscillate .  There is then most likely a 
    higher noise level present that is causing the ringing. 
    It appears to me that this control does more than just volume control
    It looks like as if it is some level detector to enable the output.
    Or perhaps that the filtered signal needs to have a certain amplitude
    to overcome some set level before audio is generated.

    With signal, I find it relative hard to set the audio freq without 
    any trace of ringing, with increasing of the volume setting the ringing 
    level is increasing quite a lot as well as the desired signal. 
    Perhaps the same old problem!  

    73 Rein W6/PA0ZN