[Elecraft] KPA-200

[Ron D'Eau Claire]

-----Original Message-----
What would the K3 be like if one could order an optional plug in module to
replace the 100W PA with a 200W PA?

Just a thought...maybe I didn't get quite enough sleep

Gary

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IMX, it would be an undetectable change in signal strength under almost any
conditions. 

Over the years most engineers working in HF radio systems have found that
the minimum discernable change in a signal is about 3 dB (2:1 change in
power) under "ideal" conditions. That's 3 times greater than the 'standard'
for audio lab work, but what is found in practice given typical background
noise, minimal QSB, etc. on an HF signal.

You can test this "on the air" very easily. Just hook up with someone in a
normal QSO and then cut your power in half and see if they notice any
difference. Don't tell them what you're testing, just that you are making a
change, and see if anyone can tell you what you changed. 

If they're looking at the S-meter on one of those absurd rigs that jumps 1
or 2 S-units for every 2 dB or so of signal change, they'll see something if
you're close enough for a rock-solid signal, but they're not likely to hear
it. 

I don't normally get excited about any major change that doesn't give me a
10:1 (10 dB) improvement in power. 

Now, let's not confuse that with having an efficient station. As any QRP
enthusiast (or smart Ham at any power) will tell you, a dB here and a dB
there eventually adds to a significant change in signal strength. But the
cost/benefits ratio of doubling the power compared to the same ratio going
to the "legal limit" usually makes such a small change a bad investment. 

Ron AC7AC