All good health. Now I use this:
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Antenna - single-band dipole with shoulders at 10m, is set at a height of 5 m above the ground, homemade BalUn and RC-75 cable. Program Sdr #.
Ideally you need a cable with characteristic impedance of 50 ohms, an antenna and an antenna tuner analyzer. Adjusting the antenna must be performed on a minimum VSWR (standing wave ratio) at a predetermined frequency. Ideal VSWR is 1.
BalUn - matching device. It allows: first, to agree impedance of the antenna and the receiver; Second, it matches the symmetrical antenna (dipole my) with an asymmetric (coax) input of the receiver.
But even with such a primitive antenna farm I was able to receive signals of amateur stations in SSB modulation in the range of 40 meters. The most distant sources of signals:
R8cbr 16:06 59+ Yuri, Nizhny Tagil 2100 km;
R0cc 18:45 Khabarovsk 5400 km.
Very clearly audible radio amateurs from Ukraine, Stavropol.
Frankly, I do not even expect that such equipment can be quite comfortable to engage in radio observations. And it's in the city. Unfortunately, there is no way to get out in the field, away from the urban and industrial noise.
The quality and the ability to receive distant stations depends not only from the antenna and the receiver, but also on
passingradio waves. In my case, 40 meter range "open" in the afternoon. Later in the afternoon clearly audible stations located to the west of me. After 12 o'clock range is gradually "closed." But sometimes it happens that the whole day looking through the range, and there are one or two stations. There is no "pass".
In the future we plan to build a full-sized antenna on the "evening" a range of 80 meters and finally buy the transceiver. We can say the dream school.
73!