I live in Trois Rivières sometimes un the night i love listen AM band, i have radio from NYC, Toronto. With my tv antenna i have TV from montreal weak and short signal. Is reflexion flight? Skywave ?
DXing is hobby?
What is DXing in telecommunication?
2017-12-25 12:03 am
回答 (3)
2017-12-25 3:41 am
DX = distance
On the AM band, it might be ionospheric 'reflections', but more likely to be 'ducting'. Ducting is when the radio signal follows the curve of the earth between the surface and the ionosphere almost in the same way a light beam follows a fiber optics fiber.
The TV signals are almost certainly reflections from F2 layer of the ionosphere. Multiple reflections from the surface and F2 are not uncommon.
And yes, DX'ing is a fairly popular hobby. Can be amateurs making two way contacts as Bill mentions, or just SWL'ers (short wave listeners) digging out those weak signal from the noise.
And don't forget to exchange QSL cards.
On the AM band, it might be ionospheric 'reflections', but more likely to be 'ducting'. Ducting is when the radio signal follows the curve of the earth between the surface and the ionosphere almost in the same way a light beam follows a fiber optics fiber.
The TV signals are almost certainly reflections from F2 layer of the ionosphere. Multiple reflections from the surface and F2 are not uncommon.
And yes, DX'ing is a fairly popular hobby. Can be amateurs making two way contacts as Bill mentions, or just SWL'ers (short wave listeners) digging out those weak signal from the noise.
And don't forget to exchange QSL cards.
2017-12-25 1:09 am
not clear what your question is.
DXing is the hobby of receiving and identifying distant radio or television signals, or making two way radio contact with distant stations in amateur radio, citizens' band radio or other two way radio communications.
DXing is the hobby of receiving and identifying distant radio or television signals, or making two way radio contact with distant stations in amateur radio, citizens' band radio or other two way radio communications.
2017-12-26 9:47 pm
DX is basically a term out of hobby amateur radio meaning great distance, sky wave, or skip refraction.
At night, the low frequency of AM broadcast spreads with skip making long range reception possible.
Thousands of miles even. Some of the lower TV channels are low enough in frequency that reflection from the ionospher can bend them back to earth and enough radiated power for at least a marginal signal.
Think of the ionosphere as a mirror that reflects radio. At night, this 'skip' wave can be bounced back to earth at great distances, the lower the frequency, the closer a skip wave may be to a transmitter. this varies day to night, even sun spot activity plays a roll. Amateur radio operators may even chose a frequency band to communicate a certain distance.
Not that it is perfect, it can fade and skew RF, but does have some predictability.
SWL is an old hobby, and by choice of frequency bands, you can listen to broadcast at predetermined ranges.
I started SWL about 10 YO, and a licensed amateur at 14.
Our cabin in the mountains dead to any radio during the day, but night, pick up SLC and LAX, often very clear.
At night, the low frequency of AM broadcast spreads with skip making long range reception possible.
Thousands of miles even. Some of the lower TV channels are low enough in frequency that reflection from the ionospher can bend them back to earth and enough radiated power for at least a marginal signal.
Think of the ionosphere as a mirror that reflects radio. At night, this 'skip' wave can be bounced back to earth at great distances, the lower the frequency, the closer a skip wave may be to a transmitter. this varies day to night, even sun spot activity plays a roll. Amateur radio operators may even chose a frequency band to communicate a certain distance.
Not that it is perfect, it can fade and skew RF, but does have some predictability.
SWL is an old hobby, and by choice of frequency bands, you can listen to broadcast at predetermined ranges.
I started SWL about 10 YO, and a licensed amateur at 14.
Our cabin in the mountains dead to any radio during the day, but night, pick up SLC and LAX, often very clear.
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