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USNA "Budget" Satellite Launched and Functioning
Arpad Korossy writes: "Hey, you ran a story on this earlier, and some people expressed doubt whether a sattelite made for a tenth of the usual cost using mostly components from Radio Shack would work; well, it has. The best line in the whole article has to be 'Instead of a $50,000 antenna system, the group used a metal tape measure.""
The metal measurement tape omnidirectional antenna system was already used on the AMSAT AO-40 hamradio satellite slashdot already posted news stories about a couple of times. The interesting part is that both antennaes which used that system failed mysteriously (or alternatively the transmitters did, this is not for sure yet).
I'd like to point out to all thos who think that NASA overspends its budget the vast cost difference between developing something new, and buying a consumer product. The rocket engine which cost 20 billion for the first one is available "off the shelf" for 200,000 today. Same for "space rated" electronics, valves, cameras, etc. It's perfectly feasable to get a reliable payload working today for very little. It probably won't, however, do anything very innovative, because doing innovative requires high precision equipment which costs a lot on earth. The equipment also has to survive the takeoff, which is another matter.
I may be completely off the mark here, but I would guess that one of NASAs primary goals at the time was to _spend_ money. Any time a government can get a legitimate reason (that the general populace will actually support) to shove a huge amount of money into the economy, they will do it. This way they get to build both technical superiority, and a stronger econony at the same time.
On the topic of cutting edge vs everyday.
/184lb, Low earth orbit), compared to what it cost then?
Anyone got an estimate of how much it would cost to launch Sputnik today (83kg
So I guess all the others out there don't count? What about ESA, Russia, India, China, Israel etc.? ESA with Ariana has sth. like half of the launcher business.
And there are quite some private companies also in the business (Sea Launch...); even in the US (if you don't check beyond your borders) there's more than just NASA. Indeed, some say that NASA has actually stifled private competition (Delta-X, Rotary etc.). Maybe it's even a good thing if NASA tunes down some, provided private companies pick up where NASA left off, and are allowed to actually do business. Leave NASA with the basic scientific research stuff... that's what they're supposed to do anyway.
Where all this really matters is with the next generation of engineers, scientists and inventors entering college in the next few years. They are the ones that will benefit from this type of experimentation. Not only will students be able to get valuable hands on experience about real world engineering, but they will get others interested in the field. Developments like these bring exotic technologies down to earth and show students they can do something really challenging. With so many posts on /. about burning out, boring classes, and disillusionment, this may bring in a breath of fresh air.
The down side of having a lot of students launching small satellites is it polutes space and makes the job of tracking dangerous objects more difficult for NASA. All of these developments aren't free, because there are a lot of other financial, political and environmental concerns attached to satellites.
Huh? Antennas don't cause interference. You must use the proper antenna for the task at hand. There are plenty of commercial uses for omnidirectional antennas.
Comparing a $50,000 narrowbeam antenna to a tape measure quarter- or half-wave whip is illogical in the first place. Those $50,000 arrays are made to communicate from a spacecraft very far away to a tiny little speck of dirt called earth using as little power as possible due to the extreme distance from the sun. The tape measure variety are made to pick up signals from earth while in earth orbit - necessitating a wide receive and transmit pattern. Apples and oranges, and all that.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
it's also not good for computer equipment. there was a graphite company in the city where i grew up. i used to work in the local computer store there. they would bring in these computers that were doing odd things. when you took them apart you could see plack paths where the fans had been pusing the air. since graphite is a conductor (although weak) it would short out misc stuff in the boxes.
-- john
Hams and researchers have been using the material used in tape measures (including sometimes using tape measures from the local hardware store) since at least the AMSAT Microsats (1991, IIRC).
For low gain end-fed whips and dipoles for HF up to 70cm, they make great antennas - self deploying, keep the correct shape, and CHEAP.
NASA has used similar materials WHERE IT IS APPROPRIATE. I would not, for example, use a tape measure dipole for an S-band system for high data-rate communications from Mars. I might use it as a UHF ground-link antenna on a surface rover.
Launch Vehicle: Babylon Gun.
From March of 1988 until the invasion of Kuwait in 1990, Iraq contracted with Gerard Bull to build three superguns: two full sized 'Project Babylon' 1000 mm guns and one 'Baby Babylon' 350 mm prototype. Nine tonnes of special supergun propellant could fire a 600 kg projectile over a range of 1,000 kilometres, or a 2,000 kg rocket-assisted projectile. The 2,000 kg projectile would place a net payload of about 200 kg into orbit at a cost of $ 600 per kg. The 1000 mm guns were never completed. After the war UN teams destroyed the guns and gun components in Iraqi possession.
Courtesy of astronautix.com