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What's a dbworth

Subject: What's a dbworth
From: n0dh@comtch.iea.com (n0dh@comtch.iea.com)
Date: Wed Aug 9 18:17:02 1995
<---- Begin Included Message ---->
From: k0od@MO.NET
Reply-To: k0od@MO.NET
Subject: What's a dbworth
To: cq-contest@tgv.com

Recently I wrote that increasing a station's ERP one db might add 10% to 
its DX contest score. Several replies indicated 10% seemed a bit 
overstated. The last time I looked at this subject was a few years ago. 
Today, I took a look at some recent CQWW CW results by power level. Here 
are scores from the 1993 contest which are fairly typical of CQWW CW 

            Highest QRP score (AA2U).................   763,000
            Second highest low power score (K2SG).... 1,845,000
            Third highest high power score (K5ZD/1).. 5,569,000

 Notice the big difference between low power and high power scores. It 
seems the advantage of an extra db actually increases at higher power 
levels. Moral: If you are currently really loud, getting even louder is 

well worth the effort. Or, life is too short for 100 watts, too. 
       Jeff K0OD  St. Louis, MO  USA
            e-mail:   k0od@mo.net
<---- End Included Message ---->


Statiscally speaking your analysis is a just a "bit" weak. For starters you 
need to be looking at the effective radiated power of theses stations not just 
their power class. A QRP station running 5 watts into a pair of stacked 5 
element monobanders on 15 meters is likely to be just as competitive (if not 
more competitive) than a 100 watt station with a vertical. Location and 
operator skill level and dedication are also big big factors. The difference 
between QRP, Low power, and High Power by the way are on the order of 6 to 10 
db per step not 1 db. All things being equal I doubt 1 db makes any 

Maybe we should class contestors by ERP rather than just transmitter power :-)

Better yet a rating system analogous to SCCA ( sports cars) which would give 
hobbiest class stations (100 watts, tribander, towers less than 60') a chance 
to compete among themselves without going broke and would likely increase 
contest participation.


>From jholly@hposl62.cup.hp.com (Jim Hollenback)  Wed Aug  9 18:41:43 1995
From: jholly@hposl62.cup.hp.com (Jim Hollenback) (Jim Hollenback)
Subject: What's a dbworth
References: <199508091717.RAA26138@comtch.iea.com>
Message-ID: <9508091041.ZM25260@hpwsmjh1.cup.hp.com>

On Aug 9,  5:17pm, n0dh@comtch.iea.com wrote:
> Better yet a rating system analogous to SCCA ( sports cars) which would give 
> hobbiest class stations (100 watts, tribander, towers less than 60') a chance 
> to compete among themselves without going broke and would likely increase 
> contest participation.

hmmmm, hobbiest class? You mean those guys with the big steel and 
more aluminum than a 777 get sponsor support. Darn, I thought they
were just prime targets for the Democrats. :-).

But yes, some way of at least gauging how you stack up against others
that have simular stations would be nice. But didn't we waste megabytes
on this very subject a summer or two ago? And got nowhere? 

73, Jim, WA6SDM

>From Balmforth, Kevin D" <kbalmforth@msmail2.hac.com  Wed Aug  9 17:38:42 1995
From: Balmforth, Kevin D" <kbalmforth@msmail2.hac.com (Balmforth, Kevin D)
Subject: LPT1 port control
Message-ID: <n1404157161.76478@MSMAIL2.HAC.COM>

I'd like to turn on and turn off a pin on my PC parallel port (e.g. LPT1) to
control a particular station function.  Any PC C programmers have a
quick/dirty approach to this?
73, Kevin NC6U

>From Larry Tyree <tree@cmicro.com>  Wed Aug  9 19:00:48 1995
From: Larry Tyree <tree@cmicro.com> (Larry Tyree)
Subject: NAQP and moving
Message-ID: <199508091800.LAA08594@cascade.cmicro.com>

I enjoy moving when asked in the NAQP.  My typical effort is the 
"brief spurts of furious activity" category which was created by
Ken, N6RO, back in the CD party days.  This means I get on between cracks
of family activity for a total of 2 hours or so.

I try to give Oregon (semi-rare on CW?) to as many people that want it
as possible.  I do have good rates (because I am fresh meat) but I
enjoy being "hunted" and feeling rare.  

It is good practice for the CQ WW CW contest where moving is a key
compentency needed to maximize your score.  The NAQP is also a great
event to practice your two radio techniques.

Off the subject: I did manage to fry my TS-850S when using my C line as
the other rig.  I am totally unsure how this happened (being low power
and all that) but it might of been due to my new 80 meter antenna having
a high current point a few feet from the center of my driven element
for 40 meters.  It appears the 74LS145 decoder is toast (the second time
this has happened).  This is the chip that selects the various bandpass
filters.  The result of one of the bandpass filters being on all the 
time is reduced output starting around 10 Mhz and decreasing to a few
watts on 10 meters.  I found this out while QSYing VE5MX from 80 to 10
near the end of the contest (we finally made it on 10 after I brought
the C line up there).

I am thinking to adding some protective circuitry to prevent this from
happening again.  Maybe some clamp diodes to VCC on each output, and some
RF bypassing to ground.  The other thing to do is to take a look at
the antenna distribution between the two rigs and improve the isolation.
This might mean moving my 80 meter antenna to a tree somewhere removed from 
the rest of my antennas.

Two radios does require some different thinking about your complete 
station design, including antenna placement.

Tree N6TR

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