Topband: 160M DXing and the quasi-static process

[Charles Bibb]

160M DXing and the quasi-static process.

With the ongoing discussion of 1/8 wave verticals and the practical 
meaning of a 1db change in signal level, the following may be relevant.

First, however, let me warn everyone on the list that this post is 
fairly long and contains no "hot" DX info, nor does it reveal any 
hard-hitting technical secrets, so all you hardboiled, 
"just-the-facts" cynics should hit the delete key now. But, things 
are kind of slow on the reflector at the moment, so maybe reading 
this won't waste too much of your valuable time. Some of you will 
find what I have to say useful, if only as a source of encouragement.

I can never sit still.  I am always looking for ways to improve both 
my transmitted signal on topband and my receiving capability.  Living 
in a small town with a neglected power distribution system makes the 
latter task especially difficult.

When it comes to improving my receiving capability, I've come to view 
my quest as a quasi-static process. A what? In thermodynamics, the 
term "quasi-static process" describes a change that happens 
infinitely slowly, but other sciences have applied the term to 
processes which occur in increments so small that virtually no 
difference can be detected between individual, sequential, discrete 
steps within the process.

Two non-scientific illustrations of this come to mind:

(1) On the day that a calf is born, the farm boy picks up the newborn 
and walks around the barn, holding the calf. He does this every day. 
However, at some point, he can no longer do it. The calf has become 
too heavy, but each individual day's change in weight was not 
noticeable. If you can lift 100 pounds, you will have no trouble with 
102 pounds, etc.

(2) Second example:  Biologists will tell you that if you toss a frog 
into a pot of scalding water, he will, of course, jump out 
immediately. But, if you place a frog in a pot of room-temperature 
water and very gradually increase the heat, the frog will sit there 
until the hot water kills him. Why? Because, from one moment to the 
next, he could tell no difference in the temperature of the water. If 
it's OK one minute, the next minute will be fine, too.

What does all this have to do with 160M DXing?  Just this:

I am forever making small (sometimes tiny) improvements to my receive 
antennas; improving a ground rod here, tweaking a termination 
resistor there, installing a better common-mode choke on this feed 
line, and on and on. Most of these improvements result in only a 
slight increase in overall signal-to-noise ratio - usually less than 
1db, perhaps only 0.5db. That is to say each improvement, taken by 
itself, is un-noticeable.

So, it follows that as a 1db change in sound level lies right at the 
lower threshold of what most listeners are able to perceive as a 
change in volume, these small incremental changes (improvements) in 
total receiving performance will result in noticeable, measurable, 
and useful improvements only in the long term - as the end result of 
a continuing, ongoing process of optimization. The effect is cumulative.

Over the past couple of years, I'd be willing to bet that I have made 
over twenty such small improvements. If each one is worth only 0.5db, 
by now I have improved my signal-to-noise ratio by at least 10db!

The point is that ANY progress is progress, and while only a 
dedicated few ops will get up out of their Lay-Z Boys to work on 
their Beverage installation for a meager 0.5db improvement, no one 
would scoff at a 10db improvement. The work is a long-term 
investment. Think of it as an IRA for topband success.

73,
Charles - K5ZK