[CW] Speed vs Bandwidth

[Pedro J. Santa]

Hi all:

I've been following (or trying to) the multiple exchanges on the referenced
topic--most of which are really devoted to esotheric postulates and futile
diatribes, to say the least.. I don't think I've learned much of any
significance from this long, just too long,  string of messages regarding
this impractical and theoretic subject.  I can only say that this hogwash
has not really added much, if anything, to my enjoyment of the hobby--much
less to my passion for Morse Code.  If our younger fellows were reading the
colloquy about this nonsense, they would just join the ranks of those who
claim we ham radio operators have "lost it"...

73 Pedro..

P.S. Morse Code is forever...

73 Pedro KP3X----- Original Message ----- 
From: "David J. Ring, Jr." <n1ea@arrl.net>
To: "George, W5YR" <w5yr@att.net>; <cw@mailman.qth.net>
Sent: Tuesday, March 16, 2004 12:09 AM
Subject: [CW] We agree - Speed vs Bandwidth


> W5YR wrote:
>
> Grab your 2003 ARRL Handbook and look at Fig. 12.21 on Page 12.13 - I
> imagine that the 2004 and 2002 books have the same content in about the
same
> location.
>
> Fig. 12.21 is a graph that relates bandwidth to rise/fall time. Keying
speed
> does not enter into the graph at all for the spectral width determination.
> It does indicate the maximum keying rate for a K=3 and a K=5 circuit for a
> given bandwidth. Nowhere in the material on CW keying could I find any
> mention of keying rate influencing bandwidth.
>
///////////////////////////////////////////////////////////////////////////
>
> I really wold like to see what they say for maximum keying rate at K=3 and
> K=5 - can you post that?
>
> I agree with you - and your observations agree with me! - the bandwidth
goes
> up with code speed, but the bandwidth is much more affected by the wave
> shape.
>
> So - we've exhausted that interesting topic.  We agree!  How boring!
>
> I might make a sound file and feed it into my IC-756PRO and change the
> "voice rate" as I mentioned - that would be a hoot.  I am sure the
bandwidth
> would go up with the voice rate pulses - so we could have a new thread
about
> bandwidth goes up when you talk fast (or at least if you make faster
> pulses!)  But we need a new email reflector - how about "CW guys who think
> they're SSB operators" email list?
>
> George, you can find the relationship between keying speed (baud or baudot
> rate) and bandwidth here on the ITU web site:
>
> http://life.itu.ch/radioclub/rr/sm1138.htm
>
>
> AMPLITUDE MODULATION
> 1. Signal with Quantized or Digital Information Continuous wave
telegraphy,
> Morse code Bn = BK
> K = 5 for fading circuits
> K = 3 for non�fading circuits
>
> 25 words per minute; B = 20, K = 5  Bandwidth:100 Hz
>
> Telegraphy by on-off keying of a tone modulated
> carrier, Morse code Bn = BK + 2M
> K = 5 for fading circuits
> K = 3 for non�fading circuits
>
> 25 words per minute; B = 20, M = 1 000, K = 5
> Bandwidth: 2 100 Hz
>
> 73
>
> David Ring, N1EA
>
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