2-meter band
[4] [5] The license privileges of amateur radio operators include the use of frequencies within this band for telecommunication, usually conducted locally with a line-of-sight range of about 100 miles (160 km).
[7] In the US, that role in emergency communications is furthered by the fact that many amateur-radio operators have a 2-meter handheld transceiver (HT), also known as a handie-talkie or walkie-talkie.
Stations in a car or home might provide higher power, 25 to 75 watts, and may use a simple vertical antenna mounted on a pole or on the rooftop of a house or a vehicle.
A well-placed antenna and high-power equipment can achieve distances of up to a few hundred miles, and fortuitous propagation conditions called "signal enhancements" can on occasion reach across oceans.
The best known of these are:[citation needed] These and other well-known forms of VHF signal enhancement that allow trans-oceanic and trans-continental contacts on 2 meters are described in the subsections that follow within this section.
When a well-equipped station with its antenna well-located “high and in the clear” is operating during a signal enhancement, astonishing distances can be bridged, momentarily approaching what is regularly possible on shortwave and mediumwave.
[citation needed] Occasionally, signal bending in the atmosphere's troposphere known as tropospheric ducting can allow 2 meter signals to carry hundreds or even thousands of kilometers as evidenced by the occasional 2 meter contact between the west coast of the United States and the Hawaiian Islands, the northeast region to the Florida coast, and across the Gulf of Mexico.
These so-called "Openings" are generally first spotted by amateurs operating SSB (Single Side Band)[8] and CW (Continuous Wave)[9] modes since amateurs using these modes typically are attempting distance contacts (DX) and alert for signal enhancement events.
Two way ducting contacts can have very strong signals and are often made with moderate power, small antennas, and other types of modes.
[citation needed] Unlike some other long distance modes, high power and large antennas are often not required to make contact with distant stations via a sporadic E event.
On-board software defines what mode or band is in use at any particular time and this is determined by amateurs at so-called earth stations who control or instruct the satellite behavior.
For receiving stations located within ± 10 degrees of the geomagnetic equator, equatorial E-skip can be expected on most days throughout the year, peaking around midday local time.
The speed required to confirm a two way contact via a short lived ionized meteor trail can only be performed by fast computers on both ends with very little human interaction.
In most instances using auroral reflections on 2 meters, audio or voice is totally unintelligible and ham operators wishing to make contacts via aurora, must resort to CW (Morse code).
[10] The Irish Radio Transmitters Society has provided a series of awards for the first successful all-natural, non-bounce contacts on 2 metres between the North American and European continents.
[11] Attempts at the Brendan awards have established contact, but further examination revealed the signal was bounced off the International Space Station.
[12] Los Angeles County has a statute (which dates from 1944) concerning mounting a "shortwave receiver" in a motor vehicle.
[13] While the statute specifically states one of the forbidden bands as 150–160 MHz, most two-meter transceivers can tune into this portion of the spectrum at least as receivers, and are therefore unlawful to mount in a motor vehicle in Los Angeles County.
[citation needed] Note: Federal law preempts many local ordinances and state laws which may prohibit a licensed amateur radio operator from possessing an amateur radio based on its factory ability to receive frequencies outside of ham bands.
