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ARRL Satellite Bulletin ARLS007 (2014)

ARLS007 AMSAT Celebrates 40 Years in Space for AO-7

QST de W1AW  
Space Bulletin 007  ARLS007
From ARRL Headquarters  
Newington, CT  November 11, 2014
To all radio amateurs

ARLS007 AMSAT Celebrates 40 Years in Space for AO-7

Saturday, November 15, will mark 40 years since the AMSAT-OSCAR 7
(AO-7) ham radio satellite went into space from Vandenberg Air Force
Base in California. Special Event W7O will be on the air November
15-24 to commemorate the launch of AO-7, the oldest working Amateur
Radio satellite. Satellite aficionado Patrick Stoddard,
WD9EWK/VA7EWK, who secured W7O for the occasion, plans to work
satellite passes during the special event from Arizona, including
AO-7 passes. He also hopes to recruit other operators to participate
in the celebration from other locations and on other bands,
including HF.

"I am thinking of incorporating the original QSL card design AMSAT
used to confirm AO-7 reception reports from the 1970s in the W7O
card," Stoddard said. He's still seeking a good scan of both sides
of the 1970s card. "The QSL cards will be printed after the W7O
activity wraps up," he added, noting that he plans to upload W7O
contacts to ARRL's Logbook of The World (LoTW).

AO-7 was the second so-called "Phase 2" Amateur Radio satellite that
AMSAT-NA constructed and launched into low-Earth orbit. It remained
in operation until a short circuit occurred in a battery in 1981.
More than 20 years later, however, AO-7 unexpectedly returned to
life, its 2 meter beacon showing up on 145.9775 MHz. AMSAT describes
the Mode A/B bird as "semi-operational" and dependent upon its solar
panels for a reliable power source; AO-7 works only as long as its
solar panels are illuminated by sunlight. Satellite experts
speculate that AO-7's resurrection occurred when the short circuit
in the battery opened up for some reason, allowing the solar cells
to power the spacecraft. When the satellite goes into eclipse, it
powers down. Since the satellite became undead, terrestrial users
have enjoyed numerous contacts via AO-7.

The eclipse period, during which AO-7 falls silent, lasts from
mid-spring to mid-summer. According to its operating plan, AO-7
switches to Mode B (70 centimeters up/2 meters down) at 0000 UTC.
AO-7 has beacons on 29.502 MHz (used in conjunction with Mode A)
and, nominally, on 145.972 MHz (used in conjunction with Mode B and
Mode C - low power Mode B). The 435.100 MHz beacon has an
intermittent problem, switching between 400 mW and 10 mW

Stoddard said he has had heard from a lot of hams interested in
taking part in the W7O operation, but he pointed out that W7O can
only be used in areas where Amateur Radio is regulated by the FCC.
He said that he's seeking satellite operators in different parts of
the US, especially in the Eastern US capable of working Europe,
North Africa, and South America, as well as other North American

In addition to satellite bands, Stoddard said, he'll take signups
for 1-hour increments on HF (excluding 60 meters) plus 6 meters, for
CW, SSB, and digital modes, but he'd like to avoid having two
stations operating at W7O on the same band/mode combination at the
same time.

Contact Stoddard for more information at, .

"Once I get some operating commitments from operators, I will
publish the schedule through a link on my WD9EWK entry and
my web page," Stoddard said. "This way, others will know where and
when to look for W7O during this 10-day period."

AMSAT has posted a series of photos documenting the early OSCAR
years, including AO-7, on the AMSAT web at,


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