Saturday, June 19, 2010

How to DXing using 2m band?

Here is a little info about 2m capabilities other than as local band. Study the capabilities then you can make full use of the allocated band for you. Don't mark it as a limitation to go far. With some tweaking of some knowledge, 2m can beat HF as well. The 2m Amateur Radio band is a portion of the VHF radio spectrum, stretching from 144.000 MHz to 148.000 MHz in ITU Regions 2 (North and South America plus Hawaii) and 3 (Asia and Oceania) and from 144.000 MHz to 146.000 MHz in ITU Region 1 (Europe, Africa, and Russia). This band is best known as a local band, where many opportunities for DX communications too.
Occasionally, the atmosphere's troposphere (ducting) can allow 2m signals carry hundreds of km. In rare cases, Sporadic E propagation can bring contacts well over 1600 km. This band is also utilized amateur radio satellites conjunction with the 70cm(430MHz till 440MHz) band with a Low Earth Orbit satellite(LEO).
DXing also allowed using speeding Morse code when very short bursts of signal can be bounced off the ionized gas trail of meteor showers. This is often called burst transmission. Another phenomenon that produces upper atmosphere ionization suitable for 2m DXing is auroras. Since the ionization persists much longer than meteor trails, audio signals transmissions can be used, but the constant movement of the ionized gas leads to heavy distortion of the signals causing the audio to sound 'ghostly' and whispered. Other DX communication is moon bounce(EME). This involves high power and good antennas to reflect the VHF signals off the moon. VHF signals normally escape the Earth atmosphere, so using the moon as a target is quite practical. Due to the delay of the signal traveling to the moon and back (travel time approx. 2.5 sec), a person transmitting may hear the end of his own transmission returning.

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