Re: QCX 40


Hans Summers
 

Hi Al, all

FYI the presets are 24-turn types.

Another thing: make sure gain control is not at minimum. The audio for the unwanted sideband adjustment is taken AFTER the gain control. So if you have gain at minimum this will also show the same symptoms (trimmers have no effect).

73 Hans G0UPL 

On Thu, Sep 6, 2018, 12:25 Al Holt <grovekid2@...> wrote:
Just a suggestion, but you might want to try getting all three back to about the center of each of their ranges and go through the procedure again. Since the resistors are multi-turn without real 'stops' it can be a little tricky. They have a subtle click to them when they are at the end of their range. I'm not sure if they are 10, 15 or 20 turn types. 

R27 is the I-Q balance control and should have the greatest effect on the null. The other two resistors help balance out high and low sides of the audio bandpass. 

I hope that helps!

--Al
WD4AH

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