[CQ-Contest] How much is a dB worth ?

[Tim Shoppa]

My interpolation on CW and RTTY using my personal logs, for 24-34 hour
efforts in 48 hour contests and almost unchanged antenna system, after
adding two different amps.

Note that my numbers only track transmit power dB, not receive system dB's.
I have improved my receive system on 160M but not on the other bands in
this time.

Note that for CW tests I was often in the top 10 box for assisted LP but
now am not necessarily in the top 10 box for CW now that I enter assisted
HP. And I actually lump a couple different contests together and apply some
tweaks based on what I feel to be changes in propagation to keep things
comparable to my last year on LP.

Going from barefoot to AL-811H (8dB) doubled my QSO's and tripled my
scores. With this change I usually get S&P on first call and can often hold
a run frequency for a good time in the biggest CW and RTTY contests.

Going from AL-811H to AL-1500 (another 4dB) added another 30% to my QSO
numbers and another 50% to my scores. With this change I almost always get
S&P on first call and only rarely get pushed off a run frequency.

So making a little table, just using ARRL DX CW as an example:

100W = 1000Q's
600W = 2000Q's (8dB more power for 3dB more Q's).
1500W = 2400Q's (12dB more power for 3.8dB more Q's)

100W = 1M points
600W = 2.7M points (8dB more power for 4.2dB more points).
1500W = 3.5M points (12dB more power for 5.5dB more points).

I would say each dB more power, means 7 to 9% more Q's.
And each dB more power, means  more points 11 to 12% more points.

There is some "compression" to the score expansion (a dB is worth more
moving from 100W to 600W, than a dB moving from 600W to 1500W).

I think this compression factor would have been less, or not there at all,
if I had improved my receive system as well as my transmit power (i.e. I am
now an alligator, all mouth, no ears).

If I had chosen WPX, the QSO ratios would be similar, but the point ratios
will be a little larger (WPX mults continue to grow quicker than ARRL DX or
CQ WW mults.)

Tim N3QE