Well Keith, I agree with you -- that's why I said I didn't want to do this
-again- here before. However, it did prompt me to setup an experiment I've
been meaning to do again, but more in depth this time, so some good will come
from it.
Contrary to what some believe, no one is claiming that we should be able to do
6k on SSB no matter what. If there's unused spectrum, it isn't "wasted", by
any means. Like I said before, there's a time & place for both types of audio.
Why that isn't obvious is beyond me. Certainly making excellent audio illegal
is over the top...
Buenos Audios,
Joe, N3JI
----- Original Message ----
From: Keith Dutson <kdutson@sbcglobal.net>
To: Joe Isabella <n3ji@yahoo.com>; Tom W8JI <w8ji@w8ji.com>; "Joe Subich, W4TV"
<w4tv@subich.com>; amps@contesting.com
Sent: Monday, July 3, 2006 7:50:23 PM
Subject: RE: [Amps] Maximum RF output in practical application: 4-250A
This thread has been Bogarted so far it is ridiculous. Look at the subject
line again. Arguing over high fidelity SSB is silly. There is nothing
wrong using high fidelity as long as no interference is caused. It
definitely is not warranted in a contest where the bands are crowded. And
if you want to be absolutely certain you are understood, use CW rather than
SSB.
73, Keith NM5G
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of Joe Isabella
Sent: Monday, July 03, 2006 4:28 PM
To: Tom W8JI; Joe Subich, W4TV; amps@contesting.com
Subject: Re: [Amps] Maximum RF output in practical application: 4-250A
I have done some experimenting with marginal S/N ratios as well. Still,
it's easier to copy signals with significant content in the 3-4 kHz range
than those with only 300-2.5k. I will be the first to tell you that it is
far from a scientific, but the extended silibance definitely added to my
comprehension under poor conditions. I also have done some "playing" with
my transmitted audio, and a majority of the time, when I focus my speech
energy between 400 and 3500 Hz, I get noticeably better results than if I
cut it at 2.5 or 2.6k. I believe that is because when in "DX" or heavy QRM
"Contest-Mode", most use their IF shifts and heavily favor that range.
Basically, I have 3.1k of occupied BW to "shift around in", and I really
think that's what makes the difference. The existance of that slightly
extended energy makes it "stand out" at the receiving end. Tinkering with
that here in my shack I have confirmed that under marginal conditions, I can
pick out the stations with more upper frequency content than those without.
All I can say is that when there is significant noise & QRM, that extra
couple hundred Hz of articulation seems to make a difference.
Has anyone else experimented with that?
Joe, N3JI
----- Original Message ----
From: Tom W8JI <w8ji@w8ji.com>
To: Joe Isabella <n3ji@yahoo.com>; "Joe Subich, W4TV" <w4tv@subich.com>;
amps@contesting.com
Sent: Monday, July 3, 2006 4:01:29 PM
Subject: Re: [Amps] Maximum RF output in practical application: 4-250A
> On the contrary, Joe. I can prove humans can tell the difference
> between certain letters, words, and sounds with 4k of audio that you
> can't with 2.5k.
That's certainly true with very high S/N ratios on clear frequencies,
assuming the people have normal hearing and speech.
I can prove the best S/N ratio and readability when signal levels have less
than 20dB S/N ratio occurs when SSB signals are between 2 and 3 kHz wide,
and that the most effective weak signal communications occurs with about
2kHz bandwidth.
73 Tom
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