[Elecraft] KX3-2m CW problem

[Matt VK2RQ]

Very interesting -- I hooked the KX3 up to a scope, set it at 30wpm on 2m with VOX OFF, and sent a continual stream of dits. This is what I saw:
http://www.vk2rq.ampr.org//images/IMG_0271.jpg

The dits are in fact quite uneven (some nearly twice as long as others), and if you listen to a continuous stream of dits it is indeed obvious to the ear. Also as you say, this problem does not occur on the other bands.

It seems there may be some sort of timing issue in the firmware; I guess this will get added somewhere on the "to-do" list.

73, Matt VK2RQ.

> On 22 Nov 2014, at 10:17 pm, paul hippenmeyer <p_hippenmeyer at bluewin.ch> wrote:
> 
> Hi Matt,
> 
> Thanks for your response! Good idea, but it is not a RF feedback. It happens also with VOX=off (RF output power=0). With a audio record (e.g. Audacitiy or scope) of the sidetone you can see, that dot length is very unregular (set speed to 40 wpm). If you do the same on a HF band, each dot has the same lenght - perfect.
> 
> On 2m CW is useful with low speeds only. On higher CW speeds the sidetone is very irritating for keying.
> 
> tnx es 73, paul hb9axl
> 
> 
> 
> 
> Just tried 2m CW using a begali paddle plugged in to the KX3 internal keyer, the CW sounds fine to me (up to 30wpm at least, unfortunately that's about as fast as I can go). I'm wondering if you might be having some sort of RF feedback issue? What sort of antenna setup do you have?
> 
> 73, Matt VK2RQ
> 
> On 22 Nov 2014, at 4:05 am, paul hippenmeyer<p_hippenmeyer at bluewin.ch>  wrote:
> 
> Hi all,
> 
> CW on 2m is a problem. Especially with speeds higher than 25 wpm the timing of the sidetone becomes very unregular (eg. continues keying of dots only). With an external keyer the problem seems to be even worse. QRQ CW sounds very dirty.
> 
> CW on HF bands is perfect.
> 
> Any others who can confirm this problem?
> 
> 73, paul
> hb9axl
> 
> MCU 2.25
> DSP  1.30
> 
>