[Elecraft] Re: KX1, R32 After thought

Wed Nov 12 14:16:01 2003

Thanks Wayne,

I had forgotten to put it in when I first built my KX1.  You may recall, I
complained about key thumps in my earlier executive summary.  After I added
it, there was a marked reduction in thump just as you describe.  I haven't
noticed any thing else other than a slight reduction in audio output.
73,
N2XE

John Ceccherelli

                      Wayne Burdick                                                                                           
                      <[email protected]        To:       John C Ceccherelli/Fishkill/IBM@IBMUS                                
                      m>                       cc:       [email protected]                                             
                                               Subject:  Re: KX1, R32 After thought                                           
                      11/12/2003 10:57                                                                                        
                      AM                                                                                                      

Hi John,

R32 raises the cutoff frequency of the high-pass filter formed by C17, C18,
and
the input resistors internal to U4 (LM386). This reduces the effect of
low-pitched or DC audio artifacts during keying in the presence of high
noise or QRM.

73,
Wayne
N6KR

John C Ceccherelli wrote:
>
> Exactly why was R32 added????

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