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BALUN 1:1 lijkt te helpen

Vervolg BALUN 
Woensdag avond mooie avond geen wind aangename temperatuur. Piet Paulusma had via Radio Noord de gehele ochtend  om de 10minuten  ...haast gewaarschuwd voor pittige buien,  dus de korte broek kon aan.

 mast omlaag, de Balun schijnt te werken  minder RF  beneden .
De PC audio set bromt veel minder. Ben niet zo'n BALUN aanhanger maar dit type kan niet veel kwaad  minimaal verlies geïntroduceerd slechts een kort stukje coax kabel 50Ω P.E.schuim gasgevuld.
Kon  21Mhz  ca 200kHz lager in de CW band afstemmen door iets langere dwars staafjes sectie [D] gebruikt als 21MHz tuning C   tussen de traps van 14 en 21. Deze zijn erg belangrijk als ze door corrosie geen goed contact maken is de afstemming op 15m gelijk zoek.
Eerst nog geprobeerd  2 capacitief staafjes 50cm ( halve las elektrode )  parallel aan de originele te plaatsen. Dat gaf ca 400kHz lagere afstemming op 21 ! iets te veel van het goede. 
Mogelijk was er toch overgangs weerstand  die na de modificatie weg was. Maar deze top C is de enige afstemming voor 21MHz effectief. 
 14MHz  kon iets hoger door verkorten van de sectie [B] tussen de traps.

--------- 
1:1 Balun / mantelstroom smoorspoel  voor de  "Hidaka" 4 band hf dipool
Nu wel veel RF in de shack  met de H43 75Ohm kabel.
SWR is  niet al te best vooral  15M

Misschien zit er toch ook iets fout.

Hopelijk is 16uH voldoende =  6 ferriet busjes (Van Dijken elektronica) meer kon ik niet in het originele HIDAKA   doosje proppen.
 16uH  XL 7MHz  ca 700Ω 
14MHz 1400 ,21 2100Ω  bij beter weer zal ik het proberen.










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