K3 Auto Notch Distortion

[Tobyp]

Distortion of the Auto Notch does exist,  how bad depends on the strength of the signal you are listening to.

This has a lot to do with whether the notch is inside or outside the
AGC circuit.  I THINK on the K3 the auto notch is outside the AGC,  and on the upconversion rigs like a 7800 Icom,  it is on the inside of the AGC circuit.  This makes for the best quality sounding auto notch.  

I don't think this can be changed in the K3   The other thing about having the notch set up like it is in the K3 is that a strong notched signal can seriously desense a signal you are trying to listen to.  This is not good,   so I usually try to use the manual notch to prevent problems.  

Toby  W4CAK
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[Arie Kleingeld PA3A-2]

Toby,

The notch is outside de AGC loop. Reason: there's a long story about IMD
and hardware AGC, which I won't quote here. Elecraft never came up with
a programmed DSP/hardware AGC solution that would dampen this effect a bit.
A pumping AGC is probably not considered an issue. To which I disagree.
I would think that there would be enough IMD headroom in the K3 to
improve the reception a bit in this case.

But if it isn't there, it's not there. No receiver is perfect. Not even
the K3.
Luckily there are a lot of good features in the K3 to compensate my sad
feelings about this item.

73 to all,

Arie PA3A

Op 12-3-2013 15:38, Toby Pennington schreef:
>
> This has a lot to do with whether the notch is inside or outside the
> AGC circuit.  I THINK on the K3 the auto notch is outside the AGC,  and on the upconversion rigs like a 7800 Icom,  it is on the inside of the AGC circuit.  This makes for the best quality sounding auto notch.
>
>

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