[Jim] Ah, but not when the entire process is delayed by 17mS!
The dit starts 17mS later and completes 17mS later.
The first dit is sent in its full length and the op on the other end never
even hears the difference.
Operator delay is also part of the entire CW operation.
It takes me much longer than 18mS to move my finger from resting on the "F"
key to punching the "F4" (which sends my call sign in CW). Sometime I'm
faster, sometimes I'm slower. So what difference does it make if the first
dit comes 17mS later?
When I was running NTS traffic nets using FULL QSK, back in the 60's, if the
receiving op missed a letter or two, he simply hit a short burst of dits to
interrupt the op that was sending. THAT STILL WORKS, even with 25mS delay.
We must be clear on what we are trying to accomplish with QSK.
I contend that hearing between characters (not individual dits) is every bit
as good as hearing between dits, and if all I can accomplish is hearing
between words, for all practical purposes, that's still good enough, from an
operational standpoint.
I think there are two threads of thought here.
1. Technically, what exactly is true full QSK?
2. Practically speaking, how far can we deviate from that and not impact the
usefulness of QSK?
ALSO, there are two reasons for not using the technical definition pure QSK:
1. It would burn relay contacts on amps with open-frame relays.
2. Even if we compensate for the delay to avoid burning relays (i.e, shift
the process by 17mS), if we do not add more delay (hang) on the tail end,
the clackety-clack-clack of the open-frame relay trying to follow CW keying
will drive humans out of the shack!
Basically all of this added delay is a crutch to help cope with the
deficiencies of not using expensive vacuum relays in some of the amplifiers.
Amplifier noise is no different than audio distortion when it comes to
fatiguing an operator. Both are undesirable when you are sitting down for
long hours of operation (like contesting).
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Brown
On Wed,9/24/2014 4:08 PM, Carl Moreschi wrote:
> At 40 wpm, a dit time is 30 msec. So why would an 18 msec delay
> remove QSK even at 40 wpm.
Because it shortens the dit by more than half.
73, Jim
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