K2: sidetone mod

[Andre]

Hi All,

I am not entirely satisfied with the K2's sidetone (at 600 Hz). So I wanted to implement the WJ4P mod (Feb 2000). Simple: 47K in series with C24, and 47mH from RP5 pin 7 to pin 10 (GND). --- While the soldering iron was warming up I looked at the control board schematics (Rev. F, 1/27/04). There I found R11=47K going to C24 and L1=82mH (basically) from RP5 pin 7 to GND. I looked again at my board (stamped "Rev B, 2002", serial no. 5519): Oops, these parts are already there!

So here is my question: Has the mod already been incorporated in revisions of the board (including mine)? I am not sure about the additional 47K. But two inductors in parallel looks like a strange concept to me.

73 de andre dm1aa

[Andre]

A bit of research on the net and I found the answer to my question: Yes, Elecraft has cleaned up the sidetone (well, sort of) in later revisions of the board, including mine. So the mod I mentioned is obsolete. I have found no further suggestions for improvement. It appears that I'll just have to live with the sidetone as it is. What's wrong with it? Well, it is slightly impure, giving a "chattering" effect to my ears, which is annoying at speeds above 30 wpm.

73 de andre dm1aa