[Elecraft] K2 Sidetone

[David Pratt]

Hello Chris and Stewart -
I carried out the mod to my K2 Revision A board way back in October 
2000, following the instructions by WJ4P and still on the Elecraft web 
site.  I have to say that following these instructions I changed the 
very raspy sidetone to a near sinewave matching my preferred sidetone 
frequency of 550 Hz.  I believe that Elecraft incorporated a similar mod 
when they brought out the Revision B board.
http://www.elecraft.com/Apps/sinewave_sidetone_mod.htm

73

David
G4DMP/G3KEP

In a recent message, G3SJJ <g3sjj at btinternet.com> wrote ...
>Yes, I did wonder about the K2DSP. Haven't got one here, yet!  The mod 
>certainly makes a difference though.
>
>Keep up the CW, Stewart!
>
>73 Chris G3SJJ
>
>
>Stewart Baker wrote:
>> Although I am not really a CW man I spent a few hours in the recent 
>>BERU  contest. After a while I began to get a bit 'fed up' with the 
>>raspy sidetone,  and looked at the reflector achieve for a solution. I 
>>saw that G3SJJ had  recently done a mod that involved adding a small 
>>board to hold the components.
>>
>> I was almost about to go this route but found that this method of 
>>modification  would likely get in the way of the K2DSP board that sits 
>>above it. So here is  what I did.
>>
>> a) I removed C33 and L1.
>> b) I soldered C33 (2.2uF) in the L1 position
>> c) I stuck L1 to the BACK of the PCB close to C33 pads with double sided tape
>> d) I soldered  the (+) terminal of a 1uF capacitor to C33 (+) pad
>> e) The other leg of the 1uF is soldered to L1
>> f) The circuit is completed by soldering a 100 ohm from L1 to C33 ( -) pad
>>
>> This way all components except the 2.2uF capacitor are now out of the 
>>way on the  back of the control PCB.
>> The improvement in sidetone quality achieved has been very noticeable.
>>
>> 73
>> Stewart G3RXQ