[Antennas] Questions on installed dipole

2002年1月17日 13:31:49 +0200

Dear friends of the list 
MY question on a previous mesage has not been replied. Last week i have amde 
a temporory dipole antenna with a wire of 0.5mm diametter (telphonic wire) the 
one part supported on trees and the other supported over and by TV cables. 
The part over trees was 12 m but the other part was 16 m.Height is abt 3 m 
above ground. 
Connecting wire was twin 1.5 mm wire , conecte to the 300 OHm input of the 
ICOM RR75 ( has digital S meter) 
Using it i found that reversing the wires in the 300Ohm input threre was soem 
little directivity , lower signal (coresponding to the wire conected on the main) of 
up to 2 S units (or 12-15dB) even a antenna tuner is used! 
Making comparisons with my main 16 m wire #12 signal is on most cases up to 
2 S units less in my most wanted bands , but but with much lesser noise.( over 
15 db) height of this antenna is 5 m above ground. 
MY questions are: 
It is corect that tress can effect reception? 
It is corect that reversing the poles of the dipole can seem as using a diferent 
antenna? 
It is also corect that the low signal in receiver is due to very thin wire? 
MY intention is later to install one 6 band inverted V.Maximum height will be abt 
12m Do you have any ideas? 
___________________________________________
pen-DX sejak 72 - anggota World-DX-Club 2104,Play DX, dll
PP: R75/HF150/MVT7100/D2935 + 16m/1x1 + 
MFJ16010/1040/1025/752c/462 
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