[Elecraft] KPA500 (another view)

[Alan Bloom]

Interesting experiment Dave.  I think that kind of test is valid for VHF
operation.  But on HF it is very rare to hear a signal at a constant
level like that.

Normally signal strength varies considerably from moment to moment due
to fading.  Even if the average signal level is right at the noise
level, most of the time it will be well above or well below that level.
A dB or two increase or decrease will vary the percentage of time the
signal is copyable, but only a little.  The QRM also varies in signal
strength from moment to moment.

Of course, louder is always better.  But unless you are a big-gun
contester, where winning or losing depends on a few extra contacts over
the course of the weekend, I think you'd have a hard time noticing a
couple dB difference in normal operation.

I am just about to order a 2-element SteppIR Yagi.  I decided that the
extra dB or two of the 3-element model is not worth another $450.  :=)

Alan N1AL


On Tue, 2012-01-17 at 16:52 -0700, David Gilbert wrote:
> A power ratio of 3 (1500 watts versus 500 watts) is just under 5 db.  
> Check out these audio files (CW, though ... not SSB) I generated to see 
> what kind of impact that can have for readability of signals near the 
> noise threshold.
> 
> http://www.ab7e.com/weak_signal/mdd.html
> 
> 73,
> Dave   AB7E
>