Hi Andy !
From my own experiments I would suggest to move the loading coil from
Base-load to top-load, situated at the top of the tube just below the
top hat. This position gives significantly more current into the 2m long
tube than base-loading.
Sorri, nothing to be seen on 475.625 from you, not even the faintest
line on the waterfall. (Distance is 731 km)
"mobile use" sounds very interesting to me, that could be a challenge !
The body of the car is an integral part of the antenna, so the earth rod
may not give comparable results.
73 de dg3lv Tobias
Am 10.06.2014 18:53, schrieb André Guyé:
Hi to all.
I am thinking now about the design of a short vertical antenna, for MF
mobile use in next winter season.
To night I’ll test this first configuration : a 2 meters high tube (2 cm
of diameter) and a top hat (wheel shape) 80 cm of diameter. It needs
about 2.4 mH base coil tuning. The *TX is 3 Watts output*. Base voltage
is 2,2 kV RMS.
*I’ll test this small antenna to night*, beginning at 2000 TU on WSPR2
MF band. The expected ERP is about 1 mW.
All reports be welcome. Note that to night the testing antenna has his
base on the garden with a ground earth rod, so it is not installing on
my car.
73 de Andy. F6CNI - JN19QB
------------------------------------------------------------------------
<http://www.avast.com/>
Ce courrier électronique ne contient aucun virus ou logiciel malveillant
parce que la protection Antivirus avast! <http://www.avast.com/> est
active.
|
