[Elecraft] K2 sidetone

[Vic K2VCO]

Hans Johansson wrote:
> I am the happy owner of K2 #5169. It functions fb but I am
> very dissatisfied with the sidetone.I have read all posts on
> modifying the sidetone and done all of them but I still have'
> thumps on the sidetone. It's not a big problem at slow speeds
> but when I work 30 wpm or more it is very irritating. Is there
> anyone who has fixed it please tell me how to do.

One thing that I noticed is that the thumps are less when you use the 
headphone jack on the front panel than when you plug the phones into the 
auxiliary speaker jack on the rear.

The thump is very low frequency, and I've taken to using an external 
audio filter to remove it entirely.  If you can find phones that have a 
'communications' instead of high-fidelity frequency response this will 
fix it as well.

> I am on my way to give up and build a separate sidetone
> oscillator ( a copy of my excellent OMNI V osc.).
> My second question: Is there any point where I can find 
> keyed 5V (or 8V or 12V) ?

I'd just rectify a little RF and use it to gate the oscillator.
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco