>
>Back when I was a pup, I was very much impressed by W3AFM's QST series on
>station design. One aspect that struck me as particularly interesting was
>his use of the marginal cost of a dB as a means of deciding where to invest
>next in his station.
>
>Rereading the series 30+ years later, some of the specific numbers he came
>up with seem questionable, but the basic concept is certainly sensible, and
>maybe worth an updated article on the subject. Rather than put my ideas
>down and then (if I got up the courage) circulate them to the reflector, I
>thought I would invite you all to give me your thoughts first (direct e-mail
>please, for the sake of reflector bandwidth). Any finished article will
>give credit to contributors, while (as usual) reserving any blame for
>mistakes to the author. At a minimum, I promise to summarize and make the
>summary available.
>
>Here are some of the questions that occur to me. Feel free to answer these,
>and to add your own pet issues. I am well aware that there are many, many
>variables, and that there will be no single answer -- but at least I hope to
>suggest a way of thinking about the subject that each reader can apply to
>his/her particular situation, interests, etc. Questions:
>
>1. How does the value of a dB of station performance vary between
>contesting and DXing? It has been said that for contesters a dB means an
>entire layer of stations previously unworkable now becomes workable. Is
>that true? Is there a corresponding figure of merit for DXing? How can it
>be measured?
>
>2. How should a station designer "weight" changes that affect both
>receiving and transmitting performance (e.g. tower height, antenna gain)
>compared with those that only affect one or the other? For example, some
>receiving improvements are really cheap (per dB), but may run into overall
>system limitations (atmospheric noise,etc.).
>
>3. How should I treat the question of balancing transmitting and receiving
>performance? How do you tell if you're an alligator, or the opposite?
>
>3. What are appropriate rules of thumb for calculating the marginal cost of
>a dB of amplifier? Tower? Antenna gain?
>
>4. How should I deal with station changes that don't affect the strength of
>signals (either transmitted or received), but that arguably improve the
>station's ability to achieve its goals (e.g. packet for DXing, computer
>contest logging software with new capabilities such as band-mapping or super
>check partial)?
>73, Pete Smith N4ZR (ex W8QZR, HL9TM, K4FOK, 3B8DT)
>n4zr@contesting.com
>
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73, Pete Smith N4ZR (ex W8QZR, HL9TM, K4FOK, 3B8DT)
n4zr@contesting.com
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