[TowerTalk] perspective

[Tom Rauch]

> We can estimate the worth of a system db by comparing the top contest
> scores between the high power and low power categories. 

As long as the operators and locations are the same we can. 
Otherwise, we have more variables to remove.

> Several years ago I did a study of moonbounce contest scores and stations
> to determine what kind of antenna system would be needed to give a top
> score on 2 meters. I found that in that contest 1 db would be worth
> approximately 25 qsos (2 meters only). The formula is still close but
> varies somewhat from year to year depending on activity level and quality
> of propagation conditions. 
> 
> The challenges of contesting on 160, 80 and 40 meters are similar to
> moonbounce contesting: You are dealing with quite a few marginal strength
> signals compared to the higher bands. It would seem that the dbs would be
> more important on these bands than the higher bands.

Moonbounce is very dissimilar to HF or other terrestrial systems.

When working moonbounce, everyone shares the same basic 
"path". The path has very predictible characteristics, and you have 
all the time necessary to wait-out any momentary fading. The 
operator doesn't handle a high rate, and so the equipment is mainly 
the limit.

Let me give a low-frequency analogy to that. I work the VK/ZL 
contest on 160 every year. I win that contest by a large margin 
every year. That happens because even though I am not a good 
rate operator, I can dig signals out of the noise. Everyone 
essentially has the same path from the USA to VK and ZL, and my 
station is bigger. I can hear weaker signals, and they can hear me 
better. The station is the primary cause and effect on QSO's.

The same would happen on moonbounce.

Now that doesn't happen in other contests because different areas 
have different propagation and the rates are high. Operating 
convenience, propagation, operator ability to maintain a high rate, 
and random luck enter the equation. 

To tell the difference, we really have to do a blind test at one 
station.

Let's put an ALC derived step power control at a station and have it 
driven from the logging computers clock. We could bump power in 
one dB steps like 0,  -1, -2, and -3 dB in short five minute steps at 
each level without the operator knowing.

After two or three contests, we should have some good data.

   
73, Tom W8JI
w8ji@contesting.com

--
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com