[Elecraft] Side Tone

[David Pratt]

In message <43BBA05D.9050403 at m0bin.demon.co.uk>, Charles 
<m0bin at m0bin.demon.co.uk> writes
>I built K2 Nr 413 and made lots of CW contacts, the built in Mojo was great.
>I stopped using it because the crystal oscillator in the side tone was 
>not a pure sine wave and it became offensive to my ear. I only use CW.
>
>I have been informed by a K2 op that the more recent versions have a 
>better side tone.

That is correct, Charles. There was a mod by WJ4P, called the "Sinewave 
Sidetone Mod" which involved fitting a 47K resistor in series with C24 
(0.0027uF) on the control board and soldering a 39mH choke across pins 7 
& 10 of RP5.  Ensure that C33 is a 2.2uF.  If not, replace it.

There is a document around about the mod somewhere and I am trying to 
locate it. If I find it I will e-mail it to you.

The later Revision B K2 has a sinewave mod incorporated.

73 de David G4DMP