K3 - RF Board - C238 - AGC change

[N2TK]

A year or so ago there was discussion about adding additional caps to C238
to reduce IMD. I believe it was two 1-uf caps.

What was the outcome of that? Did it make a noticeable difference in pileups
or for weak signal detection?

Is it a recommended mod?

 

73,

N2TK, Tony

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[wayne burdick]

N2TK, Tony wrote:

> A year or so ago there was discussion about adding additional caps  
> to C238
> to reduce IMD. I believe it was two 1-uf caps.
>
> What was the outcome of that? Did it make a noticeable difference in  
> pileups
> or for weak signal detection?

Very slight.


> Is it a recommended mod?

No. However, there was very positive response to the AGC changes made  
in firmware a few months later (rev 4.51 at the time). We corrected  
two issues with the DSP code, leading to the following timely quote  
from G3TJP: "It sounds like you've scored a touchdown with this  
revised firmware...."

73,
Wayne
N6KR


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[N2TK]

Thanks Wayne,
I am using 4.61 and am happy with the AGC. Just checking to make sure I
didn't miss something.
73,
N2TK, Tony

-----Original Message-----
From: Wayne Burdick [mailto:[hidden email]]
Sent: Monday, February 04, 2013 5:21 PM
To: N2TK, Tony
Cc: 'elecraft'
Subject: Re: [Elecraft] K3 - RF Board - C238 - AGC change

N2TK, Tony wrote:

> A year or so ago there was discussion about adding additional caps to
> C238 to reduce IMD. I believe it was two 1-uf caps.
>
> What was the outcome of that? Did it make a noticeable difference in
> pileups or for weak signal detection?

Very slight.


> Is it a recommended mod?

No. However, there was very positive response to the AGC changes made in
firmware a few months later (rev 4.51 at the time). We corrected two issues
with the DSP code, leading to the following timely quote from G3TJP: "It
sounds like you've scored a touchdown with this revised firmware...."

73,
Wayne
N6KR


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