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Experimental licencees moving
low-frequency agenda forward
With no Amateur Radio low-frequency allocation in North America, stations
operating under FCC
Part 5 Experimental licenses in the US or under special experimental
authorizations in Canada nonetheless continue to research the nether regions
of the radio spectrum. By and large, LF
experimentation is occurring in the vicinity of 136 kHz - typically 135.7
to 137.8 kHz - where amateur allocations already exist elsewhere in the
world.
The FCC rejected the ARRL's 1998 petition for LF allocations at 135.7
to 137.8 kHz and 160 to 190 kHz, however, after electric utilities objected
that ham radio transmissions might interfere with power line carrier (PLC)
signals used to control the power grid.
"Most of the new LF activity of Part 5 licensees has been in the
shared 137 kHz amateur allocation available in some parts of the world,"
says low-frequency experimenter Laurence Howell, KL1X/5. "Although
not in the Amateur Radio Service, these Part 5 experimental stations continue
to add to our knowledge on propagation and engineering."
The holder of Part 5 Experimental license WD2XDW, Howell - who's also
GM4DMA - previously operated LF from Alaska. He's since relocated to Oklahoma,
and has now resumed his LF work on 137.7752 and 137.7756 kHz. Already
he's reporting some spectacular success, despite antenna limitations.
On October 28, New Zealand LFer Mike McAlevey, ZL4OL, copied WD2XDW's
137 kHz carrier "bursts" over a path of more than 13,000 km
(8000 miles).
Howell believes the reception probably marked the first trans-pacific
reception of a US-generated signal. "The land mass between Oklahoma
and the ocean was considered to be a large obstacle to long-range communications,"
Howell remarked, "but obviously not."
The next day, Jim Moritz, M0BMU, copied the LF signals of three North
American in the vicinity of 137 kHz (137.777 kHz) - including Howell's
WD2XDW and WD2XES, operated by John Andrews, W1TAG, in Massachusetts -
using Argo software, which can detect signals not otherwise readable.
The third station, Joe Craig, VO1NA, in Newfoundland, has been operating
a beacon on 137 kHz. Howell says, VO1NA's signals serve as a bellwether
of LF transatlantic propagation. LF signals of European amateurs likewise
are heard in North America.
On November 12, Andrews and another LF experimenter in Massachusetts
completed the first two-way data exchange between Part 5 Experimental
license stations on 137 kHz. Andrews worked Warren Ziegler, K2ORS, operating
as WD2XGJ in Wayland, using conventional CW. The stations are about 25
miles apart, and both used loop antennas for transmitting. Jay Rusgrove,
W1VD, some 100 miles to the south in Connecticut, monitored and recorded
the QSO.
In British Columbia, Lorne Tilley, VE7TIL, and Steve McDonald, VE7SL,
have been heard throughout North America on LF. Howell says both are starting
a formal study of variances in groundwave propagation.
Howell says the disturbed solar conditions earlier this month wiped out
long-haul paths through or close to the auroral oval during nighttime
hours - especially at higher latitudes. He notes, however, that daytime
signals over paths of between 1000 and 1500 km (620 and 930 miles) showed
increased signal strengths during the disturbances. Howell has more LF
information on his Web
site.
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