Dot length = space length. Dash length = length of two dots AND the space
between them (3 dot lengths total).
A pretty fair speed check can be made by counting dashes for five seconds.
Setting weight can be done by setting some analog meter to full scale, then
sending dots and adjusting weight for half deflection of the meter (not
necessarily half scale).
Some who operate above 50 wpm prefer weight a little lighter than that,
maybe setting to 45% meter deflection. They say this makes it easier to
copy the high speed. Some ragchewers operating at about 35 wpm prefer
heavier settings, maybe on the order of 55% meter deflection. This seems to
have a smoother sound to those operators, so is preferable for that reason.
By using the meter to set speed, you have compensated for any delays in the
rise or fall time of the theoretical mathematical computations you are
making when they are applied to the actual rig.
Mike -N4NT-
----- Original Message -----
From: "Mark Erbaugh" <mark@microenh.com>
To: <tentec@contesting.com>
Sent: Wednesday, January 16, 2002 8:07 AM
Subject: [TenTec] CW keying weight
> This is for the serious CW ops out there.
>
> I'm working on a rig control program for the Pegasus. The Pegasus lets you
> adjust the length of the dits, dahs and element spaces independently. I
have
> figured out the formula for calculating the timing of CW dits, dahs and
> spaces from WPM when using standard weighting (dah = 3 * dit = 3 * space).
> Is there an accepted standard on how to apply weighting? My assumption
would
> be that normal weight would be 100%, a weight of 80% would mean that dah =
3
> * dit * 0.80, a weight of 120% would mean dah = 3 * dit * 1.2. Is this
what
> people would expect of CW weight? What's an acceptable range of weight
> adjustment. Obviously an absolute minimum would be 33% when dahs would
have
> the same length as dits.
>
> When the weight is not 100%, how does one calculate the WPM? Is it based
on
> the length of the dit or the dah or perhaps based on the recalculated
length
> of some standard 'word' such as PARIS?
>
> When the weight is not 100%, is the length of the element space still the
> same as the length of a dit or is it 1/3 the length of the dah? Or is it
> something else, like the normal length of a dit at the adjusted WPM
> calculated above?
>
> Why do operators adjust the keyeing weight? Is it just for a
characteristic
> sound or does is improve the readability under certain conditions? If so,
> what adjustment is used under what conditions?
>
>
> Thanks and 73,
> Mark
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