Wednesday, June 20, 2007

Happy Solstice on June 21 1806 UT!

So here we are just looking for another MW-dx-season even up here in the North (or at least waiting for the beginning in about two months...)

The photo above was taken just about 24 hours before (20 June at 1805 UT) the "Holy Moment" on June 21.

From the
On June 21st at precisely 18:06 UT, Earth's north pole will be tipped to the max (23.5o) toward the Sun. Astronomers call this moment "a solstice." It marks the beginning of summer in the northern hemisphere, and winter in the southern hemisphere. The seasons are changing--Happy Solstice!

I wish You all the best during these midsummer days which are in Scandinavia often the n:o one Carneval time (crazy people going to Sauna - heat usually around +100 centigrades - then to swim even into lakes with cold water - and being outside at night with mosquitos)...
73 TK

Friday, June 01, 2007

Measuring RF-noise by SDR-RX (sdr-14)

Summer is time to check the antennas etc up here in the North when sun shines and low-band dxing at least to East & West is not possible. Two years ago I discoved the rise of noise below 1 MHz on most antennas at my rural-QTH like KAZ and long wires. A bit better with the BOG directed away from the cottage. Soon I noted that the house 500 meters away had started using the ADSL and the connection is via a old-type cable going only a few meters from my cottage´s roof! I used my miniwhip mounted on the fishing rod at about 8 m height (look at the picture) and measured a very big rise of QRM at around 700 kHz. The reception is almost impossible between 200 and 700 kHz. Above 1 MHz the situation is better and above 1200 kHz almost OK with "bottom level" around -130 ... - 110 dB (SDR-14 scale) depending on the antenna. But below 700 kHz the level rises up to - 45 dB when measured only 2 meters from the wire and yeat at about -60 dB at about 30 meters from the wire! The miniwhip itself is quite good for measurements as it really picks up noise easily (though it is a quite active antenna but really needs to be placed away from RF-noise).
Maybe I have to consult the local telephone company ?
73 TK