[K3] CW keying with Microham CW Keyer

[GW0ETF]

Folks,

I find the internal keyer of the K3 a joy to use but normally I find it more convenient to use my Microham CW keyer as it gives CAT, and interfaces with the contest loggers.

I have noticed however that with the Microham output plugged into the 'Key' input at the rear of the K3 and all the keying settings in the router set to default, that the elements are significantly shortened when observed on my analogue scope; instead of a 1:1 dit to space ratio on a dit string it is more like 40 to 60 or worse at a guess and the cw sounds decidedly choppy.

I can sort this my adding 10ms to the 'keying compensation' parameter in Router; it then looks and sounds fine. I was just wondering if, and why this should be the situation, particularly since the element timings look absolutely fine when my key is plugged straight into the 'paddle' input on the K3 and not via the Microham. Sorry I can't be more objective with timings, difficult without a storage 'scope......

While observing the keying waveforms, I would say the leading edge looks fine but the back edge has got a definite sharp transition which could do with some smoothing; no sign of overshoot but it must sound hard judging by the corner shape. Does anyone have any pix of keying waveforms for me to compare...?

73,

Stewart Rolfe, GW0ETF  (K3 #145)

[Joe Subich, W4TV-3]

Stewart,

What PTT settings are you using for the microKEYER II?

If you have a PTT delay (PTT Lead) > 0 and are using QSK, you
will definitely see some "chopping."  WinKey and microKEYER II
activate the PA PTT output with the key closure but delay CW by
the PTT Lead value.  This results in an element that is shortened
by the value of PTT Delay.  You can compensate for this condition
by setting the "keying compensation" parameter equal to the value
f the PTT Lead.  This extends the length of the element and
restores the expected dot/space ratio (weight).

73,

   ... Joe Subich, W4TV
       microHAM America
       http://www.microHAM-USA.com 
       http://groups.yahoo.com/group/microHAM 
       [hidden email]
 


 

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of GW0ETF
> Sent: Saturday, January 19, 2008 4:27 PM
> To: [hidden email]
> Subject: [Elecraft] [K3] CW keying with Microham CW Keyer
>
>
>
> Folks,
>
> I find the internal keyer of the K3 a joy to use but normally
> I find it more
> convenient to use my Microham CW keyer as it gives CAT, and
> interfaces with
> the contest loggers.
>
> I have noticed however that with the Microham output plugged
> into the 'Key'
> input at the rear of the K3 and all the keying settings in
> the router set to
> default, that the elements are significantly shortened when
> observed on my
> analogue scope; instead of a 1:1 dit to space ratio on a dit
> string it is
> more like 40 to 60 or worse at a guess and the cw sounds
> decidedly choppy.
>
> I can sort this my adding 10ms to the 'keying compensation'
> parameter in
> Router; it then looks and sounds fine. I was just wondering
> if, and why this
> should be the situation, particularly since the element timings look
> absolutely fine when my key is plugged straight into the
> 'paddle' input on
> the K3 and not via the Microham. Sorry I can't be more objective with
> timings, difficult without a storage 'scope......
>
> While observing the keying waveforms, I would say the leading
> edge looks
> fine but the back edge has got a definite sharp transition
> which could do
> with some smoothing; no sign of overshoot but it must sound
> hard judging by
> the corner shape. Does anyone have any pix of keying
> waveforms for me to
> compare...?
>
> 73,
>
> Stewart Rolfe, GW0ETF  (K3 #145)
> --

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