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Hi All
Considering RX only some around EU are getting good
results with DX reception using the small mini vertical and others seemingly
using small loops.
Of the two I wonder which is better. I expect to
be meaningful one would need both at the same QTH otherwise environmential
variations could have an effect and give different resul,ts.
My experience with larger antennas tends to
favour the vertical for DX reception.
The loop in use here is an 80metre
system favouring E/W and works well up to about say 1500 miles in the
optimum direction (e/w) and also works for the DX but well down on the
vertical.
The loop is parallel resonated for 136 khz. and the
top horizontal is at 70 ft high.
The vertical consists of 3 x inv L's each one
100 ft vertical and over 400 ft horizontal. The vertical drop
wires taper from the top to the bottom and connect to the loading coil abt
400 uH and matched to 50 ohms coax which goes to the TX/RX some 150 ft away.(air
wound loading/matching inductors)
No ferrite material in the cct and no
problems. This system is very stable and seldom changes from day to day, once in
a while in a snow storm it might wander some hertz then return to normal although provision is made for
adjustmenty if necessary.
I cannot think of any real improvements here but if
I had a small active vertical , PA0 design or similar I would try it, I could
build one but do not have the specified transistors.
In my case I think the angle of arrival of signals
is related to the reception factor ie vertical is better for the long haul low
angle sigs and the loop better for the high angle sigs.
Your comments on the smaller verts/loops
welcome.
73 de Mal/G3KEV
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