Friday, 31 May 2013

I am a fan of radio since 1978, when I entered the world of CB and later of listening radio broadcasting. My first antenna was a long wire, placed on the roof of my parents' house and connected to the CB. Imagine the TVI with only 5 watts of power .... . Then my father gave me a receiver Grundig Satellite 3000 which allowed me to discover the emission in side band and CW. My business continued until 1984, then resumed in 1989 with the reception of SSB as SWL and activities in the "ten meters lower"....then in 1997 took the amateur radio license with the current call IZ3BUG. Since then my business has continued with the discovery of the uppermost band and then, as my business has moved in 40, 80 and 160 meter bands that I still find it difficult now but very stimulating. My current station is complete and adequate for my needs, built in compliance with the wish that my philosophy of efficient antennas, low-noise, then I do not use trapped antennas but only half-wave up to 40 meters. The whole station has a 230 VAC  filtered  power supply  inductive capacitive input with reference to the ground, so I deleted a lot of noise due to switching power supplies present in household appliances and filtered the sinusoid network. So I got a S / N ratio very favorable with the elimination of all transients coming from the network supply.
I spent a lot of time in studing the profile of the mountains around my station, thus because I wanted to calculate exactly my emission and the possibility of better signals: my choise felt on half wave antennas as Gap Titan DX and the Hexbeam made by SP9IDX. Being the dx activity my main interest, the choise was compulsory towards antennas with medium/low angle of radiation, not to low because the only open direction is from est to south-west (from from 40 to 240 degrees). Being also the mountains very closed to my station the radiation angle is a fundamental to get good performances. So I place my A3S by Cushcraft in the attic and decide to purchase an Hexbeam: better S/N, low noise and anyway a two elements half wave for 6 bands. The decision was also motivated by a though: The decision was also motivated by a number of considerations: the traps increase the noise, reduce the performance and limit the bands. Also I did not want to invest too much money on a demanding structure in which the price / performance ratio is unfavorable: After months of analysis techniques (ie grade of radiation antennas, power used, analysis of the signal / noise ratio of multiple antennas considered, etc ... ). So at the end I separate the power supply network with a filter 16A (Built specifically to eliminate the switching frequency to a few tens of kHz) with reference to ground equipotential which is connected to the roof, to the electrical system and to a good electrical ground. Thanks to some tools I own, I could verify that my studies have had a good outcome: eliminate the parasitic currents, deleted, voltage transients, voltage equipotential near zero between two points (and as roof and floor or between the ground of 'electrical system and roof). Good thought ... good result!
Now I want to focus on building the 1:1 balun to isolate the antenna from the radio as here in the Dolomites thunderstorms and static electricity often cause damage to the radio, I do not want to hurt the IC 756 PRO3 ...!

Hello, good day to those who read me.


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