. Credit must be given to
The ARRL Letter and The American Radio Relay League.
so credit is given, item follows
==>LF SIGNALS CROSSING THE POND, BUT NO QSO YET
While efforts to complete a transatlantic LF QSO still have not been
successful, things have been looking up lately in the nether reaches of the
radio spectrum. Amateur Radio activity in the vicinity of 136 kHz has
resulted in several recent "sightings" of signals from the UK here in North
America. The first such signals were heard in the US in late January and
early February. A report that the AMRAD WA2XTF 136-kHz beacon in Virginia
had been heard in the UK turned out to be in error, however.
The most recent report came February 6 from Sandy Sanders, WB5MMB, in
Oakton, Virginia, who says he was able to copy Lawrence Mayhead, G3AQC, and
"dashes" from Jim Moritz, M0BMU, in the vicinity of 136 kHz. Sanders'
monitoring station is in a three-story office building.
Such weak LF signals are not actually heard but seen. Reception of weak LF
signals typically is done using spectrographic software. Signals are
transmitted using dual-frequency CW--or DFCW
(http://www.qsl.net/on7yd/136narro.htm )--or very slow-speed CW, also known
as "QRSS." LF enthusiast Dexter McIntire, W4DEX, says that in DFCW the dot
and dash elements are sent with the same duration in time being separated by
frequency, making it easier to identify a signal from weak-carrier QRM.
From his QTH in coastal North Carolina, McIntire also has copied G3AQC on
136 kHz, possibly marking the first time an amateur LF signal from the UK
has been heard and verified in the US. He also received M0BMU's LF
transmissions for a possible distance record.
"My best reception of M0BMU, Jim Moritz, occurred at 0100 UTC on the 31st of
January," McIntire said. For LF reception, he ties together both legs of his
160-meter dipole and tuned the antenna for resonance with a small
ferrite-core inductor. Moritz estimated his effective radiated power at 1 W.
McIntire's reception of M0MBU might have set a new distance record. He
calculated the distance at nearly 6394 km, and Moritz figured it at 6371
km--apparently edging out what's believed to be the record of 6311 km set by
VA3LK and IK1ODO.
Mayhead said he'd been receiving "excellent signals" from John Currie,
VE1ZJ, and Larry Kayser, VA3LK, so he decided to run his own series of
beacon tests with the idea of encouraging stations in North America to
listen.
McIntire says that on January 27, he captured some of G3AQC's DFCW
transmission--including the letter "Q"--and sent him a screen shot, which
Mayhead confirmed as his. On a subsequent evening, W4DEX copied G3AQC's
entire call sign.
"I think that we can reasonably claim that these events constitute the first
sighting of a UK station in the US," Mayhead concluded. He estimated that
his setup generates an ERP of about 350 mW.
For a while, it had been thought that an Amateur Radio Research and
Development Corporation (AMRAD) WA2XTF experimental 136-kHz beacon in
Vienna, Virginia, had been spotted in the UK. John Sexton, G4CNN, had
reported copying the AMRAD experimental beacon on 136.750 kHz on February 5
and 6, momentarily raising the excitement level at AMRAD. That turned out
not to be the case. Sanders announced this week that it was determined the
signal heard in the UK was about 5 Hz high and did not have a characteristic
"chirp" that distinguishes the WA2XTF beacon.
Like several other countries in Europe, the UK has an amateur band at 136
kHz. Experimental amateur operations have been authorized in Canada; the
AMRAD beacon in the US is licensed under the FCC's Part 5 experimental
rules.
In October 1998, the ARRL petitioned the FCC to create two amateur LF
allocations at 135.7-137.8 kHz and 160-190 kHz. The FCC has not yet acted on
the request.
McIntire is among those who'd like to see a new LF band become reality. "I'm
champing at the bit to transmit on 136 kHz!" he said.
end end end
LSK
|
