Ham Radio in Space: AO-7 “Zombie” Satellite Again Enjoying Its Time in the Sun
Read by: RANDY KJ4TFU
It’s baaaaack! Launched November 15, 1974 as the second AMSAT Phase 2 ham satellite, AO-7 may be the zombie of the Amateur Radio satellite world, having returned from the dead more than a decade ago, then periodically re-emerging. Next year, it will be 40 years old, ancient in satellite years. After its batteries succumbed to old age, AO-7 went silent in 1981, only to spring back to life in 2002, although some believe it may have resurrected itself as much as a year earlier. AMSAT describes the Mode A/B bird as “semi-operational” and “almost certainly” running solely from its solar panels. The ham satellite organization theorizes that AO-7’s batteries shorted when they failed, but the short circuit subsequently opened, allowing the satellite to return to life. This means AO-7 only works when it’s receiving direct sunlight and shuts down when in eclipse. Since the satellite became undead, terrestrial users have enjoyed numerous contacts via AO-7.
“AO-7 is alive and doing okay,” satellite observer Frank Griffin, K4FEG, reported this week. “This season’s eclipse cycle has ended.” Griffin explained that the eclipse period, during which AO-7 falls silent, lasts about 9 weeks, 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.
Read by: NICKI KF4DHK
“The satellite has started its mode switches, but it has not quite settled back down yet,” Griffin told ARRL. For example, he said, AO-7 was in Mode A at 1230 UTC on August 5, but had been reported in Mode B earlier. He suspects that even though the satellite is now in sunlight, its orientation to the sun may still affect electrical power onboard the satellite “until it gets a little further into the full illumination.” This, in turn, could degrade the transponder performance.
AO-7 has beacons on 29.502 MHz (used in conjunction with Mode A) and 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.
Potential AO-7 users are advised that due to changes in Amateur Service and Amateur Satellite Service rules, the legality of transmitting to AO-7 on its Mode B uplink is questionable, since that frequency no longer falls within an Amateur Satellite Service allocation. §97.207(c)(2) and §97.209(b)(2) of the FCC rules authorize space station and earth station operation only in the 435-438 MHz segment, and it’s unclear whether a 1974 FCC waiver might still cover operation on the original Mode B uplink frequency. — Thanks to Frank Griffin, K4FEG; AMSAT News Service; AMSAT
Safety First! Harness Saves Canadian Ham After Fall from Tower
Read by: RICK N9GRW
An unidentified ham in Edmonton, Alberta, Canada, avoided serious injury or worse after falling July 16 from a ham radio tower he was disassembling. The man, whom media reports called “a certified tower expert” fell backward from the tower and became trapped about 35 feet in the air. The Edmonton Journal quoted District Fire Chief Lorne Corbett.
“He had on the proper harness, that’s what saved him,” Corbett said. “He also had his legs entangled in the tower itself.”
When the rescue team showed up, the man was upside down, and firefighters went up the tower to stabilize him and orient him upright. Firefighters got the man down using a bucket on a fire ladder. Although bruised, he was able to walk to the ambulance.
The ARRL offers antenna and tower safety tips on its website. Universal Radio also has posted a list of general recommendations for installing outdoor antennas. — The Edmonton Journal;
Read by: MARTHA KJ4RIQ
The 52nd Antique Wireless Association (AWA) World Convention August 20-24 in Rochester, New York, will have a dual theme — the grand opening of the new AWA Museum (on August 20), and Heathkit history and equipment (the keynote speaker will be Dick Goslee, K2GI, the former manager of the Rochester Heathkit store).
The new AWA Museum is at 6925 Route 5 and 20, Bloomfield, New York. Held at the Rochester Institute of Technology Inn and Conference Center, the AWA convention promises “five day of total immersion in radio lore, artifacts and equipment.” The annual event — essentially the “Dayton” of the vintage radio collecting community — includes a huge flea market, an expanded old equipment contest, forums and presentations, a banquet, and special event station W2AN.
Register online. The AWA also is debuting a new website design, still a work in progress. Contact Roy Widermuth via the AWA Convention web page with questions or comments.
ESA and student teams kick-off Fly Your Satellite!
Read by: LARRY KC4ZOA
26 June 2013
Six student teams and their supervisors have gathered at ESTEC for the kick-off of the new Fly Your Satellite! Programme under the ESA Education Office. For the next three days, ESA experts will introduce the objectives and present the activities to be performed during the first phase of the programme.
Satellites do not need to be the size of cars or larger to perform in space. CubeSats fit into your hand and weigh no more than a bag of sugar. They have been made possible by the increasing miniaturisation of components.
In January, ESA’s Education Office announced the ‘Fly Your Satellite!’ initiative. This is aimed at offering student teams the opportunity to become familiar with good engineering practice to build and perform satellite testing in order to increase the chances of a successful mission. The 2013 edition of the programme is however only focussing on testing selected university-built satellites that are already at an advanced stage of development.
Read by: PAUL KJ4WQN
Each CubeSat has a scientific or technological mission to complete. For example, Oufti-1 from Belgium will test high-efficiency solar cells, while Politech.1 from Spain will make observations of Earth. A full list of the satellites and their objectives is given in the Notes for editors section.
‘Fly Your Satellite!’ builds on the success of the ‘CubeSats for the Vega Maiden Flight’ pilot programme. This culminated in 2012 with the launch of seven student-built CubeSats on the first flight of the new ESA Vega launcher.
The focus of the kick-off meeting will consist of coordinating the activity to be performed during the first phase of Fly Your Satellite! enabling the teams to complete the construction of their satellite. This will include extensive satellite testing in ambient conditions under the supervision of ESA specialists who will decide which satellites should participate in the next phase of the programme.
The second phase will see the satellites tested in the simulated conditions of outer space and in those the satellites will experience at launch. These will include vibration and thermal-vacuum tests. By helping to train a skilled and confident workforce, the ‘Fly Your Satellite!’ programme helps secure Europe’s future in space technology.
Read by: JERRY KE4ETY
Hams on Sat SEPT 21 at the Adventure Science Center in Nashville will be ‘maker fair’ exhibits of folks who make tech stuff – ham radio simply must be involved – we need homebrew projects – nothing storebought – please contact me regarding homebrew things which you would like to display – time tbd – probably a table or two – this is great recruiting time – spread the word and get some homebrew stuff together – 73 de Russ w4ni