Topband: Demo of the value of one dB and the cost of sending too fast

[Joel Harrison]

Wow, this is very good Frank. I can't count the number of times I've been
trying to dig out a weak stn and jokingly made the statement "If I only
had ONE dB more of signal from the station"! What's proven here is I
really wasn't joking!!!

Good info. Thanks for sharing the link to AB7E's info.

73 Joel W5ZN




>
> The weak signal CW recordings on AB7E's website are well worth
> a few minutes to listen to. His recordings clearly demonstrate
> -- much more convincingly than any other demo I've ever heard--
> the significance of one dB of improved signal strength and the cost
> of sending too fast under weak signal conditions
>
>
> http://www.ab7e.com/weak_signal/mdd.html
>
>
>
>
> My takeaways from his recordings:
>
>
> - its well worth the effort to improve your signal by as little
> as one dB
>
>
> - when signals are very weak, sending faster (especially
> at speeds faster then than 30 WPM) costs the equivalent of
> many dB of reduced signal strength.
>
>
> If you haven't already clicked on AB7E's webpage, these are
> direct links to several of his recordings.
>
>
> A weak CW signal buried in noise with the signal strength
> decremented in one dB steps,
>
>
> http://www.ab7e.com/weak_signal/6_5_4_3_2_1_0_db.mp3
>
>
>
>
> Two weak CW signals buried in noise -- slightly offset in
> frequency -- with one signal one dB stronger than the other:
>
>
> http://www.ab7e.com/weak_signal/A_vs_B_1db_v1.mp3
> http://www.ab7e.com/weak_signal/A_vs_B_1db_v2.mp3
>
>
>
>
>
> Two weak CW signals buried in noise -- slightly offset in
> frequency -- with one signal two dB stronger than the other:
>
>
> http://www.ab7e.com/weak_signal/A_vs_B_2db_v1.mp3
> http://www.ab7e.com/weak_signal/A_vs_B_2db_v2.mp3
>
>
>
>
> CW signals sent at 20, 25, 30 and 35 WPM when buried in noise.
>
> http://www.ab7e.com/weak_signal/A_vs_B_2db_v2.mp3
>
>
>
> 73
> Frank
> W3LPL
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>


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