BEGINNER'S CLASSROOM FOR MAY 2013
6 Meters: The Magic Band
It is getting gradually warmer in the Northern Hemisphere, which means
more time outdoors can be spent gardening, cleaning up from Winter,
putting up a new antenna, and the like. This time of year also brings a shift
in listening habits for many radio enthusiasts. Whether you are an amateur
radio operator or not, you might find this month's topic of interest -- for the
DX, surprise openings and types of transmissions it affords.
6 meters has long been called the "magic band" of the amateur radio
spectrum. Sometimes the area between 50 -54 MHz can seem dead, at
others much like the upper HF shortwave bands, and at even other times be
similar to FM and low-channel TV DXing. The great part about 6 meters is
that you just never know what, where or when things will happen. Although
the primary times of the year to catch great DX on 6 meters is in June/July
and again in December, patient listening can be rewarded at any time, at a
moment's notice.
If propagation conditions are good to very good at the high end of the HF
band (15, 12, 10 meter ham bands), then it is possible to have some good
DX openings on 6 meters. The more common propagation condition to occur
is the "sporadic-E" openings, which bounce signals off the E-layer of the
ionosphere. This enables a radio listener to catch stations from 1500 miles
or about 2500 km away. There are rarer openings that are "multi-hop"
sporadic-E bounces, which can make transmissions travel much, much
further. Tropospheric Ducting can occur on 6 meters, which allows signals to
travel up to 1000 miles or about 1500 km due to weather conditions and
temperature inversions -- however, this type of DX condition is more
prevalent on low-channel TV and the FM bands.
CW (Continuous Wave) utilizing Morse Code is the only mode allowed
between 50.0 - 50.1 MHz. Some hams use 50.09 MHz as the recommended
CW calling frequency, but you can hear CW QSOs even beyond 50.1 MHz if
conditions are good. SSB (Single Sideband, in this case, Upper Sideband)
can be used from 50.1 MHz upward, and the general DX area is between
50.1 - 50.4. The National SSB calling frequency is at 50.125 MHz, and
because AM transmissions are also allowed in this range, 50.4 is considered
the general AM calling frequency. There is a more detailed breakdown of the
frequency use of 6 meters at the Radio Amateurs of Canada website:
https://www.rac.ca/en/rac/services/bandplans/6m/.
The York Region Amateur Radio Club offers the following advice on
construction of an antenna for both listening and transmitting on 6 meters:
"Most long-distance VHF+ QSOs are conducted on CW or SSB; that
means horizontally polarized antennas. A dipole for 6 meters is only
9 feet, 4 inches long and is an easy construction project. Try to get
the dipole in the air as high as possible, but even 15 feet off the
ground will make some QSO's." The YRARC also mentions that Yagi
(Beam) antennas make for great transceiver antennas on 6 meters.
Of course, the most important item to own in this case is a receiver or ham
transceiver that includes the 6-meter band. Many HF ham transceivers
include this band along with those from 80 to 10 meters, and there are
communications receivers and scanners which will allow you to listen to the
6 meter band. There are even some manufacturers who in the past made
single-band ham radios for 6-meter operation. I don't know if any are still
made, but you can always check the ham fleamarkets in your area for used
6-meter transceivers.
Good luck with all your Spring and Summer listening and DXing. Until June,
73, keep smiling and keep listening,
JOE