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Topband: AS / EU QRM - The Cocktail Party Effect

To: "topband@contesting.com" <topband@contesting.com>
Subject: Topband: AS / EU QRM - The Cocktail Party Effect
From: Fred Kleber <kleberf@bellsouth.net>
Date: Mon, 25 Nov 2019 15:08:56 +0000 (UTC)
List-post: <mailto:topband@contesting.com>
Hi Top Banders,
Having operated from the other end on a number of continents, I offer the 
following explanations of why NA hams may wonder why they can't work distant 
stations: 
SE Asia - The amount of non-ham QRM in the ham bands is unbelievable.  Most 
notable are the Indonesian (and probably other countries) fisherman who 
populate wide swaths of spectrum and have little to no regard for spectrum 
allocations.  They just go buy a cheap ham rig, make it general coverage, and 
off they go.  Additionally the beacons on fishing nets can also create quite a 
racket.  Oh yes, the commercial power suppliers in poorer countries most likely 
don't even care about repairing line nose.  One other challenge is the echo 
from NA stations which is frequently present on the low bands.  Pileups 
particularly exacerbate this phenomenon.  
Europe - Here's the cocktail party analogy.  When a cocktail party starts, a 
few people come in the door, grab a drink and start talking to each other.  As 
more people join the party, the room fills up and the ambient noise (QRM) 
rises.  In order to be communicate, guests talk louder.  More people join the 
party and the audible QRM noise floor rises.  In the radio world parallel, 
equate guest's speech with RF and talking louder with running more power.  Then 
consider that many countries don't effectively regulate TX power output, and 
you have a real mess.  Most north american's can't understand when I tell them 
that if you're not at least S-9 on 80-20 meters, you're most likely not going 
to be heard.  
I hope you find this information useful.
73 & good DX,Fred, NP2X / K9VV et al.
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