[Elecraft] TX DLY distortion

[Bob Wilson, N6TV]

If you are using the internal keyer of the K3 (or KY commands), with CW QRQ
OFF, there is no timing distortion of transmitted CW elements for any value
of CONFIG:TX DLY, as long as VOX is used, and the PTT line is not closed
with a footswitch.  The internal keyer compensates for the increased TX
delay.   This works with both full break-in (QSK) and semi break-in.

CW speeds above 37 WPM are badly distorted by jitter for both internal and
external keying if you do not have a K3S or K3 with KSYN3A upgrade and CW
QRQ mode is OFF.

As noted previously, if you want a true TX DLY of 10 ms, set CONFIG:TX DLY
to 13 (not 10).

If you are using external keying from a WinKey or via serial port with
CONFIG:PTT-KEY = OFF-DTR, with VOX ON, QSK OFF (semi break-in) and no PTT
line closure, the first transmitted element will be truncated by the TX DLY
setting (minus 2 or 3 ms assuming you have a K3S or K3 with KSYN3A
upgrade).  If using full break-in (QSK), *all* trnasmitted elements will be
truncated for any value of TX DLY above 008 with external keying.

Tcompensate for that, as mentioned previously, increase the length of every
externally-keyed element by a fixed amount, using the WinKey "Keying
Compensation" and/or "1st dit extension" setting.  In the microHAM MK2R+
Router, it is now called "R/T delay", located on the Router's PTT tab (not
the WinKey tab).

None of this applies if you set CW QRQ ON.  The TX DLY drops to about 4.5
ms,  and CONFIG:TX DLY is ignored.  None of this applies if your keyer or
software holds the PTT line closed for the duration of a CW message.

I have not made any measurements on an older unmodified K3 yet.

73,
Bob, N6TV

On Mon, Jun 11, 2018 at 12:36 PM, Lee Trout <troutcm at gmail.com> wrote:

>  With the talk on using older amps, it seems I recall there was distortion
> introduced on CW if the delay was set to the higher end?  Has that problem
> been solved via firmware?
>
> Sorry if this has already been answered, but I could not find anything on
> it.
>
> 73, Lee
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